LncRNA BlncAD1 Modulates Bovine Adipogenesis by Binding to MYH10, PI3K/Akt Signaling Pathway, and miR-27a-5p/CDK6 Axis

Research on adipogenesis will help to improve the meat quality of livestock. Long noncoding RNAs (lncRNAs) are involved in mammalian adipogenesis as epigenetic modulators. In this study, we analyzed lncRNA expression during bovine adipogenesis and detected 195 differentially expressed lncRNAs, including lncRNA BlncAD1, which was significantly upregulated in mature bovine adipocytes. Gain- and loss-of-function experiments confirmed that BlncAD1 promoted the proliferation, apoptosis, and differentiation of bovine preadipocytes. RNA pull-down revealed that the nonmuscle myosin 10 (MYH10) is a potential binding protein of BlncAD1. Then, we elucidated that loss of BlncAD1 caused increased ubiquitination of MYH10, which confirmed that BlncAD1 regulates adipogenesis by enhancing the stability of the MYH10 protein. Western blotting was used to demonstrate that BlncAD1 activated the PI3K/Akt signaling pathway. Bioinformatic analysis and dual-luciferase reporter assays indicated that BlncAD1 competitively absorbed miR-27a-5p. The overexpression and interference of miR-27a-5p in bovine preadipocytes displayed that miR-27a-5p inhibited proliferation, apoptosis, and differentiation. Further results suggested that miR-27a-5p targeted the CDK6 gene and that BlncAD1 controlled the proliferation of bovine preadipocytes by modulating the miR-27a-5p/CDK6 axis. This study revealed the complex mechanisms of BlncAD1 underlying bovine adipogenesis for the first time, which would provide useful information for genetics and breeding improvement of Chinese beef cattle.

miR-27a-5p alleviates periodontal inflammation by targeting phosphatase and tensin homolog deleted on chromosome ten

INTRODUCTION

MicroRNAs (miRNAs), a type of non-coding RNA, have been demonstrated to be essential posttranscriptional modulators in oral diseases and inflammatory responses. However, the specific role of miR-27a-5p in periodontitis requires further investigation. In this study, we used both cellular and animal models to determine how miR-27a-5p affects the pathogenesis of periodontitis and its associated biological functions.

METHODS

Quantitative real-time polymerase chain reaction and western blotting were used to analyze the expression of cytokines, phosphatase and tensin homolog deleted on chromosome ten (PTEN), and miR-27a-5p transcription. Investigation of alveolar bone resorption and inflammation of the periodontium in ligature-induced periodontitis in mice was performed using micro-computed tomography (micro-CT), hematoxylin-eosin (HE) staining, and tartrate-resistant acid phosphatase (TRAP) staining. The binding of miR-27a-5p and PTEN was predicted using the TargetScan database and experimentally confirmed using dual luciferase reporter gene assays.

RESULTS

The inflamed gingiva showed lower levels of miR-27a-5p. Macrophages from miR-27a-5p^-/- mice produced much higher quantities of pro-inflammatory cytokines owing to the stimulation of Porphyromonas gingivalis lipopolysaccharide, and miR-27a-5p^-/- mice with ligature-induced periodontitis also exhibited more severe alveolar bone resorption and damage to the periodontium. Target validation assays identified PTEN as a direct target of bona. Blocking PTEN expression partially reduced inflammation, both in vitro and in vivo.

CONCLUSIONS

miR-27a-5p alleviated the inflammatory response in periodontitis by targeting PTEN.

miR-27a-5p inhibits acute rejection of liver transplantation in rats by inducing M2 polarization of Kupffer cells through the PI3K/Akt pathway

Liver transplantation (LT), a major therapy for end-stage liver disease, is often associated with acute rejection (AR). MicroRNAs (miRNAs) have been implicated in AR-related gene regulation. In this experiment, the mechanism of miR-27a-5p in AR of LT was studied. Allotransplantation model (LEW-BN) and syngeneic transplantation model (LEW-LEW) of rat orthotopic liver transplantation (OLT) were established. miR-27a-5p was overexpressed in recipient rats 28 days before LT to detect its effects on LT pathology, liver function, and survival time. Kupffer cells (KCs) were isolated and treated with lipopolysaccharide (LPS) and miR-27a-5p overexpression. miR-27a-5p overexpression reduced lymphocyte numbers around portal areas and central veins after LT and mitigated degeneration of epithelial cells of the bile duct. Expression levels of IL-10 and TGF-β1 were increased while IL-12 was decreased. Liver function damage was alleviated and the survival time of rats with LT was prolonged. miR-27a-5p induced M2 polarization of rats with AR after LT and LPS-treated KCs in vitro and promoted activation of the PI3K/Akt pathway in KCs. Inhibition of the PI3K/Akt pathway averted induction of miR-27a-5p on M2 polarization of KCs. Taken together, miR-27a-5p inhibited AR after LT in rats by inducing M2 polarization of KCs through the PI3K/Akt pathway.

LncRNA growth arrest specific transcript 5 inhibits the growth of pituitary neuroendocrine tumors via miR-27a-5p/cylindromatosis axis

The long noncoding RNA growth arrest-specific transcript 5 (GAS5) has been reported to function as a suppressor in many cancers. However, the role and mechanism of lncRNA GAS5 in pituitary neuroendocrine tumors (PitNETs) remain unclear. Here, we found that lncRNA GAS5 and cylindromatosis (CYLD) expression was downregulated in invasive PitNET tissues and was negatively correlated with miR-27a-5p expression. LncRNA GAS5 overexpression inhibited proliferation of PitNETs cell line MMQ and GH3 cells and induced cell apoptosis, simultaneously, inhibited miR-27a-5p expression and increased CYLD expression. Moreover, miR-27a-5p mimic significantly decreased the luciferase activities of lncRNA GAS5 and CYLD luciferase reporter vector and downregulated CYLD expression, while miR-27a-5p inhibitor increased the expression of CYLD in MMQ and GH3 cells. Furthermore, RNA-immunoprecipitation assay revealed the direct binding between lncRNA GAS5 and miR-27a-5p. Additionally, miR-27a-5p mimic or silenced CYLD attenuated the effect of lncRNA GAS5 on MMQ and GH3 cell proliferation. In vivo lncRNA GAS5 overexpression inhibited GH3 cell tumor growth, while miR-27a-5p mimic or silenced CYLD attenuated the effect of lncRNA GAS5 on GH3 cell tumor growth. These results suggest that lncRNA GAS5 acts as an endogenous sponge by binding miR-27a-5p to increase the expression of its target gene CYLD, thereby inhibits PitNETs cell proliferation and tumor growth.

miR-27a-5p-Abundant Small Extracellular Vesicles Derived From Epimedium-Preconditioned Bone Mesenchymal Stem Cells Stimulate Osteogenesis by Targeting Atg4B-Mediated Autophagy

Osteoporosis (OP) is a disease affecting the elderly and is characterized by incremental fractures and bone fragility. Small extracellular vesicles (sEVs) derived from mesenchymal stem cells have been demonstrated to possess potent regeneration potential. In this study, we evaluated the osteogenesis effects of sEVs derived from Epimedium-preconditioned bone mesenchymal stem cells (EPI-sEV) from osteoblasts and ovariectomized (OVX) rats. The underlying mechanism of EPI-sEV-induced osteogenesis was explored by RNA-sequencing and verified by transfection with the corresponding mimic and inhibitor. EPI-sEV stimulated osteogenic differentiation of osteoblasts and moderated both bone mass and microstructure in OVX rats. Sequencing identified a unique enrichment of a set of microRNAs (miRNAs) in EPI-sEV. Overexpression or inhibition in vitro demonstrated that the osteogenesis-inducing potential was primarily attributed to miR-27a-5p, one of the most abundant miRNAs in the EPI-sEV fraction. Dual-luciferase reporter assays showed that miR-27a-5p promoted osteogenesis through direct suppression of Atg4B by targeting its 3' untranslated region. Additional experiments showed that miR-27a-5p suppressed autophagy that was activated in OVX rats. Moreover, osteogenic differentiation was ablated by the intervention with rapamycin in osteoblasts. These data report the regenerative potential of EPI-sEV to induce osteogenic differentiation of osteoblast cells leading to bone formation. This process is achieved by delivering sEV-miR-27a-5p to target Atg4B for further autophagy stimulation.

Silent FOSL1 Enhances the Radiosensitivity of Glioma Stem Cells by Down-Regulating miR-27a-5p

Since few reports have mentioned the role of FOSL1 in the radiotherapy sensitivity of glioma, this study would dig deep into this aspect. Cancer stem cells (CSCs) isolated by magnetic bead assay were identified by microscopy, qRT-PCR and western blot. The number of apoptotic cells was counted 72 h after X-ray irradiation to evaluate the sensitivity of cancer cells to radiotherapy. The effects of radiotherapy, FOSL1 and miR-27a-5p on basic cell functions were detected by functional experiments. The expressions of FOSL1, apoptosis-related genes and miR-27a-5p were detected by qRT-PCR and western blot as needed. The differential expression of FOSL1 and the effect of miR-27a-5p on survival rate were analyzed using GEPIA and UALCAN, respectively. FOSL1 was found highly expressed in glioma cells and patients. The appearance of spherical cells and high expressions of CSC-related markers indicated the successful isolation of CSC-like cells. The increment of X-ray dose enhanced the sensitivity of cancer cells to radiotherapy. Radiotherapy down-regulated cell viability and the expressions of FOSL1 and Bcl-2, but up-regulated cell apoptosis and the expressions of cleaved caspase-3 and Bax, which could be partially reversed by overexpressed FOSL1 or further enhanced by shFOSL1. MiR-27a-5p was highly expressed in in patients with glioma, which was associated with poor prognosis, while shFOSL1-inhibited miR-27a-5p expression enhanced the sensitivity of glioma stem cells to radiotherapy. In vivo experiments further verified the results obtained from in vitro experiments. Silent FOSL1 strengthened the radiosensitivity of glioma by down-regulating miR-27a-5p.

LncRNA FAM230B Promotes Gastric Cancer Growth and Metastasis by Regulating the miR-27a-5p/TOP2A Axis

AIM

Long non-coding RNAs serve as key components of competing endogenous RNA (ceRNA) networks that underlie tumorigenesis. We investigated the pathogenic roles of lncRNA FAM230B and its molecular mechanism in gastric cancer (GC).

METHOD

The levels of FAM230B expression in five gastric cancer cell lines and in human gastric mucosal cells were compared by quantitative RT-PCR. To analyze the function of FAM230B in GC, we overexpressed FAM230B in AGS cells, silenced FAM230B in MGC-803 cells, and tested the effect of FAM230B on tumor growth in nude mice. The interaction between miR-27a-5p and FAM230B was predicted by a bioinformatics analysis and then verified with a dual-luciferase reporter assay. We also further investigated the role and mechanism of FAM230B by forcing overexpression of miR-27a-5p in MGC-803 gastric cancer cells.

RESULTS

We found that FAM230B was highly expressed in gastric cancer cell lines and mainly located in the cytoplasm. FAM230B overexpression promoted the proliferation, migration, and invasion of AGS cells and repressed their apoptosis; it also facilitated tumor growth in vivo. In contrast, FAM230B knockdown suppressed the proliferation, migration, and invasion of MGC0803 cells, but enhanced their apoptosis and inhibited tumor growth in vivo. MiR-27a-5p expression was suppressed by FAM230B overexpression in AGS cells. MiR-27a-5p inhibited the proliferation, migration, and invasion of gastric cancer cells, and promoted the apoptosis of gastric cancer cells by reducing TOP2A (topoisomerase 2 alpha) expression.

CONCLUSION

Our study showed that lncRNA FAM230B might function to promote GC. FAM230B functioned as a ceRNA by sponging miR-27a-5p and enhancing TOP2A expression.

MicroRNA MiR-27a-5p Alleviates the Cerulein-Induced Cell Apoptosis and Inflammatory Injury of AR42J Cells by Targeting Traf3 in Acute Pancreatitis

Acute pancreatitis (AP), a sudden inflammatory process of pancreas, is painful and may contribute to death. The aberrant expression of miR-27a-5p has been reported in many types of cancers and diseases including AP. Thus, it is urgent to manifest the functions and mechanism of miR-27a-5p in AP. The levels of miR-27a-5p, tumor necrosis factor (TNF) receptor-associated factor 3 (Traf3) in serum of AP patient, or cerulein-treated AR42J cells were detected by qRT-PCR. Functionally, the apoptotic rate, the protein levels of Bcl-2 and Bax, the caspase-3 activity, and the levels of IL-1β, IL-6, and TNF-α in cerulein-treated AR42J cells were measured by flow cytometry, Western blot, caspase-3 activity assay, and qRT-PCR and ELISA assay, respectively. In addition, the putative target of miR-27a-5p was predicted by TargetScan online database, and the dual luciferase reporter assay and RNA immunoprecipitation (RIP) assay were conducted to verify this interaction. Cerulein-treated mouse AP model was established to explore the role of miR-27a-5p in AP in vivo. The level of miR-27a-5p was notably downregulated in AP patients and cerulein-treated AR42J cells. The functional experiments indicated that miR-27a-5p mimics attenuated the promotion effects on cell apoptosis and the inflammatory response in AR42J cells caused by cerulein. The interaction between miR-27a-5p and Traf3 was predicted by TargetScan online database and validated by dual luciferase reporter assay and RIP assay. Following qRT-PCR results exhibited that Traf3 was apparently enhanced in cerulein-treated AR42J cells. The further functional experiments disclosed that Traf3 overexpression relieved the inhibitory effects on cell apoptosis and the inflammatory response induced by miR-27a-5p mimics in cerulein-treated AR42J cells. Moreover, miR-27a-5p alleviated cerulein-induced injury in vivo. In this study, we established the cerulein-treated AR42J cells as AP model in vitro. We validated that miR-27a-5p was significantly downregulated, and Traf3 was strikingly upregulated in AP patient and/or cerulein-treated AR42J cells. The further mechanistical and functional experiments unraveled that miR-27a-5p regulated Traf3 to relieve the cerulein-induced cell apoptosis and inflammatory injury of AR42J cells. Therefore, this novel regulatory network may provide therapeutic target for AP patients.

The lncRNA 'UCA1' modulates the response to chemotherapy of ovarian cancer through direct binding to miR-27a-5p and control of UBE2N levels

Ovarian cancer (OC) is the leading cause of death in patients with gynecologic cancers. Due to late diagnosis and resistance to chemotherapy, the 5‐year survival rate in patients with OC is below 40%. We observed that UCA1, a lncRNA previously reported to play an oncogenic role in several malignancies, is overexpressed in the chemoresistant OC cell line OAW42‐R compared to their chemotherapy‐sensitive counterpart OAW42. Additionally, UCA1 overexpression was related to poor prognosis in two independent patient cohorts. Currently, the molecular mechanisms through which UCA1 acts in OC are poorly understood. We demonstrated that downregulation of the short isoform of UCA1 sensitized OC cells to cisplatin and that UCA1 acted as competing endogenous RNA to miR‐27a‐5p. Upon UCA1 downregulation, miR‐27a‐5p downregulated its direct target UBE2N leading to the upregulation of BIM, a proapoptotic protein of the Bcl2 family. The upregulation of BIM is the event responsible for the sensitization of OC cells to cisplatin. In order to model response to therapy in patients with OC, we used several patient‐derived organoid cultures, a model faithfully mimicking patient’s response to therapy. Inhibition of UBE2N sensitized patient‐derived organoids to platinum salts. In conclusion, response to treatment in patients with OC is regulated by the UCA1/miR‐27a‐5p/UBE2N axis, where UBE2N inhibition could potentially represent a novel therapeutic strategy to counter chemoresistance in OC.

KLF5-induced BBOX1-AS1 contributes to cell malignant phenotypes in non-small cell lung cancer via sponging miR-27a-5p to up-regulate MELK and activate FAK signaling pathway

Background

Non-small cell lung cancer (NSCLC) is a major histological subtype of lung cancer with high mortality and morbidity. A substantial amount of evidence demonstrates long non-coding RNAs (lncRNA) as critical regulators in tumorigeneis and malignant progression of human cancers. The oncogenic role of BBOX1 anti-sense RNA 1 (BBOX1-AS1) has been reported in several tumors. As yet, the potential functions and mechanisms of BBOX1-AS1 in NSCLC are obscure.

Methods

The gene and protein expression was detected by qRT-PCR and western blot. Cell function was determined by CCK-8, colony forming, would healing and transwell assays. Bioinformatics tools, ChIP assays, dual luciferase reporters system and RNA pull-down experiments were used to examine the interaction between molecules. Subcutaneous tumor models in nude mice were established to investigate in vivo NSCLC cell behavior.

Results

BBOX1-AS1 was highly expressed in NSCLC tissues and cells. High BBOX1-AS1 expression was associated with worse clinical parameters and poor prognosis. BBOX1-AS1 up-regulation was induced by transcription factor KLF5. BBOX1-AS1 deficiency resulted in an inhibition of cell proliferation, migration, invasion and EMT in vitro. Also, knockdown of BBOX1-AS1 suppressed NSCLC xenograft tumor growth in mice in vivo. Mechanistically, BBOX1-AS1 acted act as a competetive “sponge” of miR-27a-5p to promote maternal embryonic leucine zipper kinase (MELK) expression and activate FAK signaling. miR-27a-5p was confirmed as a tumor suppressor in NSCLC. Moreover, BBOX1-AS1-induced increase of cell proliferation, migration, invasion and EMT was greatly reversed due to the overexpression of miR-27a-5p. In addition, the suppressive effect of NSCLC progression owing to BBOX1-AS1 depletion was abated by the up-regulation of MELK. Consistently, BBOX1-AS1-mediated carcinogenicity was attenuated in NSCLC after treatment with a specific MELK inhibitor OTSSP167.

Conclusions

KLF5-induced BBOX1-AS1 exerts tumor-promotive roles in NSCLC via sponging miR-27a-5p to activate MELK/FAK signaling, providing the possibility of employing BBOX1-AS1 as a therapeutic target for NSCLC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-01943-5.

UVA influenced the SIRT1-miR-27a-5p-SMAD2-MMP1/COL1/BCL2 axis in human skin primary fibroblasts

Both SIRT1 and UVA radiation are involved in cellular damage processes such as apoptosis, senescence and ageing. MicroRNAs (miRNAs) have been reported to be closely related to UV radiation, as well as to SIRT1. In this study, we investigated the connections among SIRT1, UVA and miRNA in human skin primary fibroblasts. Our results showed that UVA altered the protein level of SIRT1 in a time point–dependent manner. Using miRNA microarray, bioinformatics analysis, we found that knocking down SIRT1 could cause up‐regulation of miR‐27a‐5p and the latter could down‐regulate SMAD2, and these results were verified by qRT‐PCR or Western blot. Furthermore, UVA radiation (5 J/cm²), knocking down SIRT1 or overexpression of miR‐27a‐5p led to increased expression of MMP1, and decreased expressions of COL1 and BCL2. We also found additive impacts on MMP1, COL1 and BCL2 under the combination of UVA radiation + Sirtinol (SIRT1 inhibitor), or UVA radiation + miR‐27a‐5p mimic. SIRT1 activator resveratrol could reverse damage changes caused by UVA radiation. Besides, absent of SIRT1 or overexpression of miR‐27a‐5p increased cell apoptosis and induced cell arrest in G2/M phase. Taken together, these results demonstrated that UVA could influence a novel SIRT1‐miR‐27a‐5p‐SMAD2‐MMP1/COL1/BCL2 axis in skin primary fibroblasts, and may provide potential therapeutic targets for UVA‐induced skin damage.

PCOS serum-derived exosomal miR-27a-5p stimulates endometrial cancer cells migration and invasion

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among reproductive-age women. Women with PCOS have a 2.7-fold increased risk for developing endometrial cancer (EC). This study was performed to investigate the potential stimulatory effects of serum exosomes isolated from patients with PCOS on EC cell lines and to explore the underlying mechanism. EC cell lines exposed to exosomes derived from PCOS patients serum exhibited an enhanced migration and invasion phenotype. Next, sequence-based analysis of exosomal miRNA was conducted to screen the differentially expressed miRNAs in serum exosomes from PCOS patients and normal controls. The levels of 55 mature miRNAs significantly differed in serum exosomes from PCOS patients compared with those from normal controls. Real-time PCR was used to verify the expression of eight of these miRNAs, among which miR-27a-5p was the most significantly elevated in PCOS patients serum exosomes. The role of miR-27a-5p in EC migration and invasion was further investigated via miR-27a-5p mimics or inhibitor transfection in Ishikawa and HEC-1A EC cell lines. In addition, the SMAD4 gene was identified as the target of miR-27a-5p by several target prediction databases and was validated by a luciferase assay. SMAD4 mRNA and protein levels were downregulated in EC cells transfected with the miR-27a-5p mimics, but upregulated in cells transfected with the miR-27a-5p inhibitor. Furthermore, in vitro experiments results confirmed that miR-27a-5p prohibited migration and invasion via SMAD4 downregulation. Thus, serum exosomal miR-27a-5p may play a role in EC development in PCOS patients.

Effect of microRNA-27a-5p on apoptosis and inflammatory response of pancreatic acinar cells in acute pancreatitis by targeting PTEN

To investigate the apoptosis and inflammatory response of microRNA-27a-5p (miR-27a-5p) in pancreatic acinar cells of acute pancreatitis (AP) and its related mechanisms. Rat pancreatic acinar cell line AR42J was treated with caerulein (10nmol/L) to construct an acute pancreatitis cell model. Quantitative real-time polymerase chain reaction was performed to measure the expression of miR-27a-5p; The miR-27a-5p mimic was transfected into cell, and the apoptosis rate of the cells was detected by flow cytometry; The levels of TNF-α, IL-1, and IL-6 in the culture supernatant were determined by enzyme-linked immunosorbent assay; TargetScans database predicted and dual luciferase reporter gene assay verified the relationship between miR-27a-5p and the phosphatase and tensin homolog deleted on chromosome 10 (PTEN); The recovery experiment explored the apoptosis and the effects of inflammatory responses. The expression of miR-27a-5p decreased gradually (P < 0.05) and the expression of PTEN increased gradually (P < 0.05) with the prolongation of acting time. Upregulation of miR-27a-5p significantly promoted cell apoptosis (P < 0.05) and inhibited inflammatory response (P < 0.05); The TargetScans database predicted that the 3'UTR of PTEN contains a base complementary to the miR-27a-5p seed region. Cotransfection of wild-type vector (PTEN-WT) with miR-27a-5p mimic or miR-27a-5p inhibitor significantly affected the relative activity of luciferase (P < 0.05), and no significant impact was observed in mutant PTEN-MUT. Compared with miR-27a-5p + pcDNA group, transfection of miR-27a-5p mimic and pcDNA-PTEN significantly increased the expression of PTEN (P < 0.05), decreased the apoptotic rate (P < 0.05), and increased the inflammatory response (P < 0.05). miR-27a-5p induced apoptosis and inhibited the inflammatory response of pancreatic acinar cells in AP by targeting PTEN.

miR-27a-5p Attenuates Hypoxia-induced Rat Cardiomyocyte Injury by Inhibiting Atg7

Acute myocardial infarction (AMI) is an ischemic heart disease with high mortality worldwide. AMI triggers a hypoxic microenvironment and induces extensive myocardial injury, including autophagy and apoptosis. MiRNAs, which are a class of posttranscriptional regulators, have been shown to be involved in the development of ischemic heart diseases. We have previously reported that hypoxia significantly alters the miRNA transcriptome in rat cardiomyoblast cells (H9c2), including miR-27a-5p. In the present study, we further investigated the potential function of miR-27a-5p in the cardiomyocyte response to hypoxia, and showed that miR-27a-5p expression was downregulated in the H9c2 cells at different hypoxia-exposed timepoints and the myocardium of a rat AMI model. Follow-up experiments revealed that miR-27a-5p attenuated hypoxia-induced cardiomyocyte injury by regulating autophagy and apoptosis via Atg7, which partly elucidated the anti-hypoxic injury effects of miR-27a-5p. Taken together, this study shows that miR-27a-5p has a cardioprotective effect on hypoxia-induced H9c2 cell injury, suggesting it may be a novel target for the treatment of hypoxia-related heart diseases.