Diagnostic value and role of serum miR-15a-5p in patients with schizophrenia.

BACKGROUND: More and more studies have confirmed that the heredity plays an important role in mental disorders, especially microRNA. The objective of this research was to explore the level of miR-15a-5p in patients with schizophrenia (SZ), and to evaluate the feasibility of this miRNA as a diagnostic marker of SZ. METHODS: The serum level of miR-15a-5p in patients with SZ and healthy people was detected by RT-qPCR. ROC curve was established to evaluate the clinical diagnostic significance of miR-15a-5p in SZ. Pearson correlation coefficient was used to evaluate the correlation between miR-15a-5p level and PANSS score. Logistic regression was used to assess the risk factors of SZ. A rat model of SZ was established, and the effects of miR-15a-5p on the behavior of SZ rats were observed through water maze test and open field test. RESULTS: The serum level of miR-15a-5p in patients with SZ was significantly increased, and ROC analysis revealed that miR-15a-5p had clinical diagnostic value in SZ. High level of miR-15a-5p was positively correlated with the positive symptom, negative symptom and general psychopathology subscore of patients. Logistic regression results showed that miR-15a-5p was a risk factor affecting the occurrence of SZ. Animal studies showed that the serum level of miR-15a-5p was elevated in the SZ rats, and inhibiting the expression of miR-15a-5p has a positive effect on improving the cognitive function and anxiety behavior of SZ rats. CONCLUSIONS: Serum miR-15a-5p is a risk factor for SZ, which is of great significance for the diagnosis of SZ.

PRKCA Promotes Mitophagy through the miR-15a-5p/PDK4 Axis to Relieve Sepsis-Induced Acute Lung Injury.

Acute lung injury (ALI) caused by sepsis is a common respiratory critical illness with high morbidity and mortality. Protein kinase C-alpha (PRKCA) plays a protective role in sepsis-induced ALI. However, the detailed molecular mechanism of PRKCA in ALI caused by sepsis is unclear. Animal and cell models of sepsis were established by cecal ligation and puncture (CLP)-surgery and lipopolysaccharide (LPS)/interferon-gamma (IFN-γ) treatment, respectively. Lentivirus transfection was used to overexpress PRKCA. H&E staining and lung injury in CLP-surgery mice were evaluated. Gene expression was evaluated using qPCR and Western blotting. The expression of TNF-α, IL-1ß, and IL-6 was examined using qPCR and ELISA. The expression of LC3 and TOM20 was evaluated using immunofluorescence assays. Cell apoptosis was assessed using a flow cytometry assay. The bond between miR-15a-5p and PDK4 was confirmed by dual-luciferase reporter gene and RNA immunoprecipitation assays. In vivo and in vitro, PRKCA overexpression reduced lung injury to prompt mitophagy and inhibit the inflammatory response, ROS production, and cell apoptosis. miR-15a-5p was highly expressed in macrophages treated with LPS/IFN-γ and was negatively mediated by PRKCA. The overexpression of miR-15a-5p reduced the effects of PRKCA upregulation in macrophages. miR-15a-5p could restrain mitophagy in LPS/IFN-γ-treated macrophages by directly targeting PDK4. Furthermore, PDK4 knockdown reversed the inhibition of cell apoptosis and inflammatory factor release caused by miR-15a-5p silencing. The PRKCA/miR-15a-5p/PDK4 axis alleviated ALI caused by sepsis by promoting mitophagy and repressing anti-inflammatory response.

A novel circRNA, hsa_circ_0069382, regulates gastric cancer progression.

Aberrant expression of circRNAs is closely associated with the progression of gastric cancer; however, the specific mechanisms involved remain unclear. Our aim was to identify new gastric cancer biomarkers and explore the molecular mechanisms of gastric cancer progression. Therefore, we analyzed miRNA and circRNA microarrays of paired early-stage gastric cancer samples. Our study identified a new circRNA called hsa_circ_0069382, that had not been reported before and was expressed at low levels in gastric cancer tissues. Our study also included bioinformatics analyses which determined that the high expression of hsa_circ_0069382 regulated the BTG anti-proliferation factor 2 (BTG2)/ focal adhesion kinase (FAK) axis in gastric cancer lines by sponging for miR-15a-5p. Therefore, proliferation, invasion, and migration of gastric cancer is impacted. miR-15a-5p overexpression partially restored the effects of hsa_circ_0069382. This study provides potential new therapeutic options and a future direction to explore for gastric cancer treatment, and biomarkers.

Exosomal lncRNA Mir100hg derived from cancer stem cells enhance glycolysis and promote metastasis of lung adenocarcinoma through mircroRNA-15a-5p/31-5p.

BACKGROUND: Exosomes are a new class of molecular entities in the metastatic microenvironment, which can mediate bidirectional communication between cells. While exosomes-mediated interactions between tumor cells and other cell populations in the tumor microenvironment have attracted most attention, little is known about the significance of exosomes in mediating the interaction between non-stemness cancer cells and cancer stem cells during cancer progression. METHODS: The structure, sequence and downstream target miRNAs of lncRNA Mir100hg were predicted by online web resources. The bioinformatics prediction results were validated with experimental verification: exosome tracing, electron microscopy, Luciferase assay, metabolomics sequencing and mouse tail vein model of pulmonary metastasis. A complex regulatory network of "cancer stem cells-exosomal lncRNA-non-stem cancer cells" was constructed. RESULTS: This study demonstrates firstly that lncRNA Mir100hg is upregulated in lung cancer stem cell LLC-SD (Lung cancer stem cells) and can be delivered to non-stemness cancer cells LLC (Lewis lung cancer cells) via exosomes. In LLC, Mir100hg targets miR-15a-5p and miR-31-5p which leads to the increase of the global glycolytic activity of lung cancer cells and consequently, the enhancement of their metastatic capability. CONCLUSION: We delineated a complex regulatory network that utilized by cancer stem cells to transfer their high metastatic activity to the low-metastatic non-stemness cancer cells through exosomal Mir100hg, thereby providing new mechanistic insights into the communication between two heterogeneous tumor cells. Video Abstract.

Melatonin suppresses serum starvation-induced autophagy of ovarian granulosa cells in premature ovarian insufficiency.

OBJECTIVES: Premature ovarian insufficiency (POI) refers to the decline and cessation of ovarian functions in women under 40 years of age. Melatonin (MT) acts as a protective for the ovary. This study elucidated the role of MT in autophagy of granulosa cells (GCs) in POI via modulating the phosphatidylinositol-3-kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) pathway. METHODS: The expression levels of microRNA (miR)-15a-5p, signal transducer and activator of transcription 3 (Stat3), and relevant hormones in the clinically collected serum samples of POI patients and healthy controls were examined. Human ovarian granulosa-like tumor cells (KGN) underwent serum starvation (SS) treatment to induce POI cell models and then received MT treatment. The expression levels of miR-15a-5p, Stat3, p-PI3K/PI3K, p-Akt/Akt, and p-mTOR/mTOR in KGN cells were tested via quantitative real-time polymerase chain reaction and Western blotting. KGN cell viability was assessed by MTT assay and the protein levels of autophagy-related markers Beclin-1, microtubule-associated protein light chain 3 II/I, and p62 were detected by Western blotting. The binding relation between miR-15a-5p and Stat3 was verified via the dual-luciferase reporter gene assay. Functional rescue experiments were performed to probe the underlying role of miR-15a-5p/Stat3/the PI3K-Akt-mTOR pathway in KGN cell autophagy. RESULTS: miR-15a-5p was increased whilst Stat3 was decreased in the serum of POI patients and SS-induced KGN cells. MT inhibited miR-15a-5p and Stat3, activated the PI3K-Akt-mTOR pathway, and repressed cell autophagy in SS-induced KGN cells. miR-15a-5p targeted and repressed Stat3 expression. Upregulation of miR-15a-5p or downregulation of Stat3 or the PI3K-Akt-mTOR pathway promoted KGN cell autophagy. CONCLUSION: MT suppressed miR-15a-5p and activated Stat3 and the PI3K-Akt-mTOR pathway, finally impeding SS-induced autophagy of GCs.

LncRNA ZFAS1 regulates the hippocampal neurons injury in epilepsy through the miR-15a-5p/OXSR1/NF-κB pathway.

Long non-coding RNAs (lncRNAs) have been confirmed to be involved in epilepsy development. It has been reported that lncRNA ZFAS1 plays a vital regulatory role in epilepsy progression. Therefore, the role and molecular mechanism of ZFAS1 in epilepsy progression deserve further investigation. Mice status epilepticus (SE) model was constructed, and hippocampal neurons were isolated from mice hippocampus tissues. The expression of ZFAS1, miR-15a-5p and oxidative stress responsive 1 (OXSR1) were determined by quantitative real-time PCR. ELISA assay was used to detect the concentrations of inflammation factors. Cell viability and apoptosis were examined by MTT assay, EdU staining and flow cytometry. Western blot analysis was conducted to measure protein levels, and the productions of SOD and MDA were measured to assess cell oxidative stress. Dual-luciferase reporter assay and RIP assay were employed to validate the relationship between miR-15a-5p and ZFAS1 or OXSR1. LncRNA ZFAS1 was highly expressed in SE mice and SE-stimulated hippocampal neurons. Silenced ZFAS1 promoted viability, while inhibited inflammation, apoptosis and oxidative stress in SE-induced hippocampal neurons. MiR-15a-5p could be targeted by ZFAS1, and its inhibitor also reversed the suppressive effect of ZFAS1 knockdown on SE-induced hippocampal neurons injury. In addition, OXSR1 was a target of miR-15a-5p, and its silencing also could relieve SE-induced hippocampal neurons injury. OXSR1 overexpression reversed the inhibition effect of miR-15a-5p on SE-induced hippocampal neurons injury. Moreover, ZFAS1 positively regulated OXSR1 expression by sponging miR-15a-5p, thereby activating the NF-κB pathway. LncRNA ZFAS1 might contribute to the progression of epilepsy by regulating the miR-15a-5p/OXSR1/NF-κB pathway.

Circular RNA circFADS2 is overexpressed in sepsis and suppresses LPS-induced lung cell apoptosis by inhibiting the maturation of miR-15a-5p.

BACKGROUND: Circular RNA circFADS2 plays protective roles in LPS-induced inflammation, which promotes sepsis, suggesting its involvement in sepsis. METHODS: Expression of circFADS2, mature miR-15a-5p, and miR-15a-5p precursor in plasma samples from sepsis patients and healthy controls was determined by RT-qPCR. The circFADS2 expression vector was transfected in lung cells, followed by the measurement of the expression levels of mature miR-15a-5p and miR-15a-5p precursor to study the role of circFADS2 in miR-15a-5p maturation. Cell apoptosis was analyzed by cell apoptosis assay. RESULTS: CircFADS2 was upregulated in sepsis and inversely correlated with mature miR-15a-5p, but not miR-15a-5p precursor. In lung cells, circFADS2 overexpression decreased the level of mature miR-15a-5p, but not miR-15a-5p precursor. LPS treatment decreased miR-15a-5p expression and increased circFADS2 level. Cell apoptosis analysis showed that circFADS2 overexpression reduced miR-15a-5p overexpression-induced apoptosis of LPS-treated lung cells. CONCLUSIONS: CircFADS2 is upregulated in sepsis to suppress LPS-induced lung cell apoptosis by inhibiting miR-15a-5p maturation.

M2 macrophage-derived exosomal microRNAs inhibit cell migration and invasion in gliomas through PI3K/AKT/mTOR signaling pathway.

BACKGROUND: Glioma, the most common primary brain tumor, account Preparing figures for 30 to 40% of all intracranial tumors. Herein, we aimed to study the effects of M2 macrophage-derived exosomal microRNAs (miRNAs) on glioma cells. METHODS: First, we identified seven differentially expressed miRNAs in infiltrating macrophages and detected the expression of these seven miRNAs in M2 macrophages. We then selected hsa-miR-15a-5p (miR-15a) and hsa-miR-92a-3p (miR-92a) for follow-up studies, and confirmed that miR-15a and miR-92a were under-expressed in M2 macrophage exosomes. Subsequently, we demonstrated that M2 macrophage-derived exosomes promoted migration and invasion of glioma cells, while exosomal miR-15a and miR-92a had the opposite effects on glioma cells. Next, we performed the target gene prediction in four databases and conducted target gene validation by qRT-PCR, western blot and dual luciferase reporter gene assays. RESULTS: The results revealed that miR-15a and miR-92a were bound to CCND1 and RAP1B, respectively. Western blot assays demonstrated that interference with the expression of CCND1 or RAP1B reduced the phosphorylation level of AKT and mTOR, indicating that both CCND1 and RAP1B can activate the PI3K/AKT/mTOR signaling pathway. CONCLUSION: Collectively, these findings indicate that M2 macrophage-derived exosomal miR-15a and miR-92a inhibit cell migration and invasion of glioma cells through PI3K/AKT/mTOR signaling pathway.

LncRNA MEG8 promotes NSCLC progression by modulating the miR-15a-5p-miR-15b-5p/PSAT1 axis.

BACKGROUND: Non-small cell lung cancer (NSCLC) is the most common tumor with severe morbidity and high mortality. Long non-coding RNAs (lncRNAs) as crucial regulators participate in multiple cancer progressions. However, the role of lncRNA MEG8 in the development of NSCLC remains unclear. Here, we aimed to investigate the effect of lncRNA MEG8 on the progression of NSCLC and the underlying mechanism. METHODS: Cell proliferation was analyzed by EdU assays. The impacts of lncRNA MEG8, miR-15a-5p, and miR-15b-5p on cell invasion and migration of NSCLC were assessed by transwell assay. The luciferase reporter gene assay was performed using the Dual-luciferase Reporter Assay System. The effect of lncRNA MEG8, miR-15a-5p, and miR-15b-5p on tumor growth was evaluated in nude mice of Balb/c in vivo. RESULTS: We revealed that the expression levels of MEG8 were elevated in the NSCLC patient tissues compared to that in adjacent normal tissues. The expression of MEG8 was negatively relative to that of miR-15a-5p and miR-15b-5p in the NSCLC patient tissues. The expression of MEG8 was upregulated, while miR-15a-5p and miR-15b-5p were downregulated in NSCLC cell lines. The depletion of MEG8 inhibited NSCLC cell proliferation, migration, and invasion in vitro. MEG8 contributed to NSCLC progression by targeting miR-15a-5p/miR-15b-5p in vitro. LncRNA MEG8 contributes to tumor growth of NSCLC via the miR-15a/b-5p/PSAT1 axis in vivo. Thus, we concluded that lncRNA MEG8 promotes NSCLC progression by modulating the miR-15a/b-5p/PSAT1 axis. CONCLUSIONS: Our findings demonstrated that lncRNA MEG8 plays a critical role in NSCLC development. LncRNA MEG8, miR-15a-5p, miR-15b-5p, and PSAT1 may serve as potential targets for NSCLC therapy.

LINC_00355 promotes gastric cancer progression by upregulating PHF19 expression through sponging miR-15a-5p.

BACKGROUND: Long non-coding RNAs exert vital roles in several types of cancer. The objective of this study was to explore the role of LINC_00355 in gastric cancer (GC) progression and its potential mechanism. METHODS: The expression levels of LINC_00355 in GC tissues and cells were detected by quantitative real-time PCR, followed by assessing the effects of LINC_00355 knockdown or overexpression on cell properties. Dual-luciferase reporter assay was utilized to identify the relationship between LINC_00355 and microRNA (miR)-15a-5p and miR-15a-5p and PHD finger protein 19 (PHF19), followed by the rescue experiments. RESULTS: The results showed that LINC_00355 was highly expressed in GC tissues and cells compared with the corresponding control. LINC_00355 knockdown decreased the viability, migration, and invasion and increased the accumulation of GC cells in G1 phase and apoptosis. Meanwhile, LINC_00355 downregulation markedly increased cleaved caspase 3 and cleaved poly (ADP-ribose) polymerase protein levels, whereas decreased cyclin D1, cyclin E, matrix metalloproteinase (MMP) 9, MMP2, and N-cadherin protein levels in GC cells. However, LINC_00355 overexpression had the opposite effects. It was verified that LINC_00355 upregulated the expression of PHF19 through sponging miR-15a-5p. Furthermore, PHF19 overexpression reversed the effect of LINC_00355 knockdown on GC cell properties, including cell viability, migration, invasion, and apoptosis. CONCLUSIONS: Collectively, these results suggest that LINC_00355 promotes GC progression by up-regulating PHF19 through sponging miR-15a-5p. Our findings may provide an important clinical basis for reversing the malignant phenotype of GC.

Knockdown of circ_0075503 suppresses cell migration and invasion by regulating miR-15a-5p and KLF12 in endometriosis.

Endometriosis is an estrogen-dependent disease. Several researches have reported the dysregulated circular RNAs (circRNAs) in endometriosis, whereas the functions of circRNAs are largely unknown. This study aims to explore the role and mechanism of circ_0075503 in migration and invasion of eutopic endometrial stromal cells. 30 paired ectopic and eutopic endometrium tissues were collected from patients with endometriosis. And primary endometrial stromal cells (ESCs) were stimulated with estradiol (E2) to establish the in vitro cellular model of endometriosis. The levels of circ_0075503, miR-15a-5p and Krüppel-like factor 12 (KLF12) were measured by quantitative reverse transcription polymerase chain reaction or western blot assays. Cell viability, migration and invasion were examined via 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide, transwell assay or western blot assays. The target relationship between miR-15a-5p and circ_0075503 or KLF12 was analyzed by dual-luciferase reporter assay and RNA Immunoprecipitation (RIP) assay. Circ_0075503 expression was elevated in ectopic endometrium and ectopic ESCs. Down-regulation of circ_0075503 suppressed E2-induced promotion of cell viability, migration and invasion in eutopic ESCs. Circ_0075503 could act as a sponge for miR-15a-5p, and KLF12 was targeted by miR-15a-5p. Inhibition of miR-15a-5p reversed the effects of circ_0075503 knockdown on E2-treated ESCs migration and invasion. Besides, miR-15a-5p repressed E2-induced promotion effects on cell migration and invasion via targeting KLF12. Circ_0075503 could regulate KLF12 expression by sponging miR-15a-5p. Knockdown of circ_0075503 inhibited E2-induced enhancement of cell migration and invasion in eutopic ESCs by regulating miR-15a-5p/KLF12 axis, indicating a novel target for the treatment of endometriosis.

Exosomal LINC00355 derived from cancer-associated fibroblasts promotes bladder cancer cell proliferation and invasion by regulating miR-15a-5p/HMGA2 axis.

We have previously demonstrated that exosomes derived from cancer-associated fibroblasts (CAFs) promote bladder cancer (BC) cell proliferation and invasion by transferring LINC00355. In this study, the molecular mechanisms underlying the pro-bladder cancer action of exosomal LINC00355 were explored. CAFs were obtained from BC tumor tissues, and normal fibroblasts (NFs) were obtained from adjacent normal tissues. Human BC cell lines (T24 and 5367) were incubated with NF-Exo (exosomes from NFs), CAF-Exo (exosomes from CAFs), CAFsi-Ctrl-Exo (exosomes from si-Ctrl-transfected CAFs), and CAFsi-LINC00355-Exo (exosomes from si-LINC00355-transfected CAFs). BC cell proliferation and invasion were evaluated by MTT and Transwell assays, respectively. The interaction between miR-15a-5p and LINC00355 or HMGA2 was examined by online bioinformatics analysis and luciferase activity assay. Results showed that HMGA2 is a direct target of miR-15a-5p, and LINC00355 functions as a sponge of miR-15a-5p to upregulate HMGA2 expression. The promoting effects of CAF-Exo on HMGA2 expression, cell proliferation, and cell invasion were hindered when LINC00355 expression was inhibited in BC cells. These promoting effects were also hindered when miR-15a-5p was overexpressed or HMGA2 was silenced in BC cells. In conclusion, exosomal LINC00355 derived from CAFs promotes BC cell proliferation and invasion by regulating miR-15a-5p/HMGA2 axis.

LINC00473 downregulation facilitates trophoblast cell migration and invasion via the miR-15a-5p/LITAF axis in pre-eclampsia.

More and more evidence has identified that long non-coding RNAs (lncRNAs) are involved in various biological process of numerous diseases. It has been reported that long intergenic non-protein coding RNA 473 (LINC00473) was associated with pre-eclampsia (PE) development. However, role and molecular mechanism of LINC00473 in PE remains elusive. Therefore, we designed this research to figure out the specific biological function of LINC00473 in trophoblasts. Firstly, we testified expressions of LINC00473 in trophoblasts of PE with RT-qPCR analysis. Then, to probe biological function of LINC00473 in trophoblasts of PE, CCK-8 assay, trans-well assays and western blot analysis were conducted in Wish and JAR cells. As for verifying interaction of microRNA-15a-5p (miR-15a-5p) and LINC00473 or lipopolysaccharide induced TNF factor (LITAF), RNA pull-down and luciferase reporter assays were carried out. Finally, rescue experiments were conducted to probe regulatory pattern of the LINC00473/miR-15a-5p/LITAF axis in trophoblasts of PE. As a result, LINC00473 presented a significant upregulation in trophoblasts of PE. Moreover, LINC00473 knockdown induced trophoblast viability, migration, invasion, and epithelial-to-mesenchymal transition (EMT) in trophoblasts. Additionally, miR-15a-5p interacted with LINC00473 and miR-15a-5p was negatively regulated by LINC00473 in trophoblasts. Simultaneously, miR-15a-5p negatively modulated LITAF in trophoblasts. Moreover, LITAF overexpression or miR-15a-5p downregulation reversed the promotive impact of silenced LINC00473 on trophoblast viability, migration, invasion and EMT. In conclusion, LINC00473 regulated migration and invasion in trophoblasts via the miR-15a-5p/LITAF axis. Our study may provide a novel insight for clinical treatment of PE.

RETRACTED: MiR-15a-5p targets FOSL1 to inhibit proliferation and promote apoptosis of keratinocytes via MAPK/ERK pathway.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the authors. According to the authors, concerns with the experimental conduct presented in the paper have been identified, in addition to the grounds that that ethical approval was not sought or confirmed for the research undertaken. After a review, the Editor has confirmed approval that this paper should be retracted as it presents a violation of the Journal's publishing policies and publishing ethics standards.

Knockdown of lncRNA PVT1 inhibits prostate cancer progression in vitro and in vivo by the suppression of KIF23 through stimulating miR-15a-5p.

BACKGROUND: Prostate cancer (PCa) greatly threatens men's lives, with high incidence and mortality. Recently, the research of long non-coding RNAs (lncRNAs) has made breakthroughs in the development of human cancers. This study aimed to figure out the role and action mechanism of lncRNA PVT1 (PVT1) in PCa. METHODS: The expression of PVT1, microRNA-15a-5p (miR-15a-5p) and kinesin family member 23 (KIF23) was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation, apoptosis, migration and invasion were assessed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT), flow cytometry and transwell assays, respectively. The protein levels of KIF23 and proliferation, apoptosis, and epithelial-mesenchymal transition (EMT)-related markers were quantified by western blot. The relationship between miR-15a-5p and PVT1 or KIF23 was predicted by starBase v2.0 and verified by dual-luciferase reporter assay. Xenograft assay was conducted to determine the role of PVT1 in vivo. RESULTS: The expression of PVT1 and KIF23 was enhanced, while miR-15a-5p expression was reduced in PCa tissues and cells. PVT1 interference inhibited proliferation, migration and invasion but promoted apoptosis of PCa cells. MiR-15a-5p was a target of PVT1, and KIF23 was a target of miR-15a-5p. The inhibition of miR-15a-5p reversed the effects of PVT1 interference and suppressed the roles of KIF23 knockdown. KIF23 expression was regulated by PVT1 through miR-15a-5p. PVT1 interference blocked PCa progression in vivo. CONCLUSION: PVT1 knockdown had effects on the progression of PCa by inhibiting the expression of KIF23 via enriching miR-15a-5p in vitro and in vivo, suggesting that PVT1 might be a novel biomarker for the treatment of PCa.

LncRNA SNHG1 exerts a protective role in cardiomyocytes hypertrophy via targeting miR-15a-5p/HMGA1 axis.

Heart failure preceded by pathological cardiac hypertrophy is a leading cause of death. Long noncoding RNA small nucleolar RNA host gene 1 (SNHG1) was reported to inhibit cardiomyocytes apoptosis, but the role and underlying mechanism of SNHG1 in pathological cardiac hypertrophy have not yet been understood. This study was designed to investigate the role and molecular mechanism of SNHG1 in regulating cardiac hypertrophy. We found that SNHG1 was upregulated during cardiac hypertrophy both in vivo (transverse aortic constriction treatment) and in vitro (phenylephrine [PE] treatment). SNHG1 overexpression attenuated the cardiomyocytes hypertrophy induced by PE, while SNHG1 inhibition promoted hypertrophic response of cardiomyocytes. Furthermore, SNHG1 and high-mobility group AT-hook 1 (HMGA1) were confirmed to be targets of miR-15a-5p. SNHG1 promoted HMGA1 expression by sponging miR-15a-5p, eventually attenuating cardiomyocytes hypertrophy. There data revealed a novel protective mechanism of SNHG1 in cardiomyocytes hypertrophy. Thus, targeting of SNHG1-related pathway may be therapeutically harnessed to treat cardiac hypertrophy.

miR-15a-5p suppresses peritoneal fibrosis induced by peritoneal dialysis via targeting VEGF in rats.

AIM: When peritoneal fibrosis (PF) causes ultrafiltration failure in peritoneal dialysis (PD) patients, PD has to be discontinued. Currently, there is no effective way to relieve PF. In this study, we aimed to determine whether miR-15a-5p is involved in PF and to determine the underlying mechanism. METHODS: Six normal rats were used as the control group. A uremic rat model was constructed using 5/6 nephrectomy in a Sprague-Dawley model. The uremic rats were randomly divided into PD, lentivirus-transfected, negative control, VEGFR-inhibited and gavage control groups. Except for the control group, all uremia rats received continuous PD for 28 days. In the lentivirus-transfected group, the miR-15a-5p plasmid was injected into the peritoneal cavity to upregulate miR-15a-5p expression. Axitinib was used to block vascular endothelial growth factor receptor (VEGFR) in the peritoneum. The mRNA levels of miR-15a-5p and VEGF were detected by qRT-PCR and FISH. Protein levels of VEGF, E-cadherin, collagen IV, fibronectin and α-SMA were detected by western blot and immunohistochemistry. RESULTS: PD leads to peritoneal thickening and fibrosis. The expression level of miR-15a-5p decreased and that of VEGF increased in the PD group than in the controls. Additionally, E-cadherin was significantly reduced while collagen IV, fibronectin and α-SMA were obviously increased in the PD group compared to controls. FISH showed that VEGF might be the target gene of miR-15a-5p. Overexpression of miR-15a-5p or inhibition of VEGFR could reverse PF. CONCLUSION: miR-15a-5p may participate in the endothelial to mesenchymal transition of PF caused by PD through VEGF.

miR-15a-5p suppresses inflammation and fibrosis of peritoneal mesothelial cells induced by peritoneal dialysis via targeting VEGFA.

Long-term peritoneal dialysis (PD) often ends up with ultrafiltration failure (UFF) which is partially caused by persistent inflammation and fibrosis of peritoneal tissues. However, the mechanism is still unclear. In the current study, the peritoneum from UFF patients demonstrated inflammation and fibrosis which were positively related to the expression of vascular endothelial growth factor A (VEGFA). The in vitro model using human peritoneal mesothelial cells (HPMCs) stimulated by high glucose or advanced glycation end (AGE) product showed consistent changes of inflammation, fibrosis, and VEGFA. What's more, we showed that VEGFA was an instigator of inflammation and fibrosis. Several microRNAs (miRNAs) have been reported to regulate expression of VEGFA elsewhere. Five of them were selected to test the expression in the peritoneum of patients with PD. Results suggested that miR-15a-5p was the most significantly downregulated one. Also, in high glucose or AGE product-stimulated HPMCs, miR-15a-5p decreased. When miRNA mimic was used to restore the expression of miR-15a-5p, high glucose-induced VEGFA was repressed. The predicted binding site between these two molecules was confirmed by the dual-luciferase assay. Restoration of miR-15a-5p restrained inflammation and fibrosis of HPMCs. TGF-ß1/Smad2 was shown to be the downstream signaling pathway and their activity was regulated by miR-15a-5p/VEGFA. In conclusion, our current study demonstrates that miR-15a-5p acts as a regulator of VEGFA mRNA and the following inflammation and fibrosis in peritoneal mesothelial cells. The miR-15a-5p/VEGFA pathway may be a potential target for preventing ultrafiltration failure in patients with PD.

MicroRNA-15a-5p suppresses cancer proliferation and division in human hepatocellular carcinoma by targeting BDNF.

We examined the expression pattern and functional roles of microRNA 15a-5p (miR-15a-5p) in human hepatocellular carcinoma (HCC). Possible miR-15a-5p aberrant expression in HCC cell lines or clinical HCC specimens was examined by quantitative real-time PCR (qRT-PCR). In HCC HepG2 and SNU-182 cells, miR-15a-5p was ectopically overexpressed by lentiviral transduction. Its effect on HCC proliferation, cancer division, and in vivo tumor growth were examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, cell cycle assay, and tumorigenicity assay, respectively. The targeting of miR-15a-5p on its downstream gene, brain-derived neurotrophic factor (BDNF), was examined by dual-luciferase assay, qRT-PCR, and Western blot, respectively. BDNF was then overexpressed in HepG2 and SNU-182 cells to evaluate its selective effect on miR-15a-5p in HCC modulation. MiR-15a-5p is aberrantly downregulated in in vitro HCC cell lines and in vivo HCC clinical specimens. Ectopic overexpression of miR-15a-5p suppressed cancer proliferation, induced cell cycle arrest in HepG2 or SNU-182 cells in vitro, and inhibited HCC tumor growth in vivo. MiR-15a-5p selectively and negatively regulated BDNF at both gene and protein levels in HCC cells. Forced overexpression of BDNF effectively reversed the tumor suppressive functions of miR-15a-5p on HCC proliferation and cell division in vitro. Our study demonstrated that miR-15a-5p is a tumor suppressor in HCC and its regulation is through BDNF in HCC.

miR-15a-5p enhances the malignant phenotypes of colorectal cancer cells through the STAT3/TWIST1 and PTEN/AKT signaling pathways by targeting SIRT4.

Colorectal cancer (CRC) continues to represent one of the major causes of cancer-related mortality and morbidity. MicroRNAs (miRNAs) are confirmed to be involved in modulating substential biological processes by affecting the expression of targeted genes, including carcinogenesis. In the present study, the expression pattern and functional roles of microRNA-15a-5p (miR-15a-5p) in CRC cells were investigated. The data from TCGA database indicated that miR-15a-5p is highly expressed in CRC tissues. Moreover, ectopic expression of miR-15a-5p facilitated the proliferation, migration, and invasion of CRC cells. Furthermore, bioinformatic analysis combinating with dual-luciferase assay revealed that SIRT4 acts as a crucial target of miR-15a-5p. Accordingly, overexpression of SIRT4 suppresses the miR-15a-5p-mediated enhancement in the proliferation, migration, and invasion of CRC cells, while the opposite phenotypes were observed after inhibition of SIRT4. Moreover, we further revealed that miR-15a-5p restrained the expression of SIRT4 to exacerbate the malignant phenotypes by modulating STAT3/TWIST1 and PETN/AKT signaling in CRC cells. Alternatively, inhibition of the miR-15a-5p/SIRT4 axis enhanced the chemosensitivity of 5-fluorouracil- and oxaliplatin-resistant HCT116 cells. Altogether, our evidence suggests that miR-15a-5p plays an essential role in promoting the proliferation, migration, and chemoresistance of CRC cells via targeting SIRT4 to modulate STAT3/TWIST1 and PETN/AKT signaling, which may serve as a promising therapeutic target for CRC therapy.