LINC01082 Inhibits Non-Small Cell Lung Cancer by Targeting the miR-543/TNRC6A Axis.

Non-small cell lung cancer (NSCLC) accounts for over 80% of lung cancer cases and have poor clinical outcomes. Increasing number of lncRNAs are reported to be implicated in the carcinogenesis of NSCLC. Previous lncRNA-seq results showed that LINC01082 was under-expressed in several cancer types. In the current study, we focused on the role of LINC01082 in NSCLC development. An online bioinformatics tool was utilized to assess the expression profile of LINC01082, miR-543, and TNRC6A in NSCLC samples. RT-qPCR analysis was performed for evaluating LINC01082, TNRC6A and miR-543 expression in cells (NSCLC cells vs. normal lung cells). Impact of LINC01082 upregulation on cell proliferation in vitro was investigated by MTT and EdU experiments. Transwell assay was applied to analyze the migration and invasion of NSCLC cells. The cell apoptosis after plasmid transfection was detected by flow cytometry. The interactions among LINC01082, miR-543 and TNRC6A were measured by RNA pulldown and luciferase reporter assays. We showed that LINC01082 levels were downregulated in NSCLC samples and NSCLC cells. Overexpression of LINC01082 inhibited NSCLC cell proliferation, migration and invasion and strengthened cell apoptosis. LINC01082 directly bound to miR-543, and miR-543 targeted TNRC6A. TNRC6A was downregulated and miR-543 was overexpressed in NSCLC cells. miR-543 inhibition suppressed malignant cellular behaviors. TNRC6A knockdown reversed the effects of LINC01082 on the malignant character of NSCLC cells. In conclusion, LINC01082 exerts an antioncogenic role in NSCLC via interaction with miR-543 to regulate TNRC6A expression.

miR-543 regulates high glucose-induced fibrosis and autophagy in diabetic nephropathy by targeting TSPAN8.

BACKGROUND: Diabetic nephropathy (DN) is one of the most common and serious complications of diabetes, which can lead to renal failure and fatality. miRNAs are an important class of endogenous non-coding RNAs implicated in a wide range of biological processes and pathological conditions. This study aims to investigate the potential functional roles of miR-543 in DN and its underlying mechanisms. METHODS: qRT-PCR was performed to detect the expression levels of miR-543 and TSPAN8 in kidney tissues of mice with DN. Western blot (WB) was used to measure the protein levels. CCK8 assay was employed to evaluate the proliferation of HK2 cells. Dual luciferase reporter assay was conducted to verify the functional interaction between miR-543 and TSpan8. RESULTS: The downregulation of miR-543 and upregulation of TSPAN8 were observed in kidney tissues of mice with DN. miR-543 mimic significantly decreased cell proliferation and autophagy in high-glucose (HG)-induced HK2 cells, and promoted cell fibrosis. We further identified a putative binding site between miR-543 and TSPAN8, which was validated by Dual luciferase reporter assay. The treatment of miR-543 mimic and miR-543 inhibitor could reduce or increase TSPAN8 protein level respectively. We further showed that the overexpression of TSPAN8 could attenuate HG-induced cell injury by reducing fibrosis and increase autophagy. The effects of miR-543 mimic in proliferation, fibrosis, and autophagy were rescued by TSPAN8 overexpression. CONCLUSIONS: Our study indicate that miR-543 mediates high-glucose induced DN via targeting TSPAN8. Interfering miR-543/TSPAN8 axis could serve as potential approach to ameliorate DN.

Circular RNA circ_0001017 Sensitizes Cisplatin-Resistant Gastric Cancer Cells to Chemotherapy by the miR-543/PHLPP2 Axis.

Resistance to cisplatin (CDDP) remains a major challenge for the treatment of gastric cancer (GC). Circular RNAs (circRNAs) have been implicated in the development of CDDP resistance of GC. However, the precise actions of circ_0001017 in CDDP resistance of GC remain to be elucidated. The levels of circ_0001017, microRNA (miR)-543 and PH-domain and leucine-rich repeat protein phosphatase 2 (PHLPP2) mRNA were gauged by quantitative real-time polymerase chain reaction (qRT-PCR). Western blot was used to analyze the protein levels of Vimentin, N-cadherin, E-cadherin, and PHLPP2. Ribonuclease R (RNase R) assay was applied to evaluate the stability of circ_0001017. Cell viability and proliferation, colony formation ability, cell cycle distribution and apoptosis, and migration and invasion were detected by the Cell Counting Kit-8 (CCK-8), colony formation, flow cytometry, and transwell assays, respectively. Direct relationship between miR-543 and circ_0001017 or PHLPP2 was verified by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. Xenograft model assay was used to assess the function of circ_0001017 in vivo. Low expression of circ_0001017 was associated with CDDP resistance of GC. Enforced expression of circ_0001017 impeded growth, metastasis, and enhanced apoptosis of HGC-27/R and AGS/R cells and sensitized them to CDDP in vitro. Circ_0001017 targeted miR-543, and circ_0001017 regulated CDDP-resistant cell behaviors and CDDP sensitivity by suppressing miR-543. PHLPP2 was a direct target of miR-543, and circ_0001017 controlled PHLPP2 expression through miR-543. Moreover, miR-543 knockdown-mediated promotion of PHLPP2 impacted CDDP-resistant cell behaviors and CDDP sensitivity in vitro. Additionally, elevated expression of circ_0001017 hindered growth of HGC-27/R cells and sensitized them to CDDP in vivo. Our findings demonstrated that enforced expression of circ_0001017 suppressed malignant behaviors and enhanced CDDP sensitivity of CDDP-resistant GC cells at least partially by the miR-543/PHLPP2 axis.

LncRNA SNHG14 accelerates breast cancer progression through sponging miR-543 and regulating KLF7 expression.

PURPOSE: Dysregulation of long non-coding RNAs (lncRNAs) is being found to have relevance to human cancers, including breast cancer (BC). The aim of this study was to further explore the functional role and molecular mechanisms of small nucleolar RNA host gene 14 (SNHG14) on BC progression. METHODS: The expression levels of SNHG14, miR-543, and krüppel-like factor 7 (KLF7) mRNA were determined by quantitative real-time PCR. Western blot analysis was used to evaluate KLF7 protein level. Cell proliferation, apoptosis, and migration and invasion abilities were detected by Cell Counting kit-8 assay, flow cytometry, and transwell assay, respectively. The direct interactions between miR-543 and SNHG14 or KLF7 were confirmed using dual-luciferase reporter assays. RESULTS: Our data indicated that SNHG14 expression was increased in BC tissues and cells, and SNHG14 knockdown mitigated the proliferation, migration, and invasion and facilitated apoptosis of BC cells. SNHG14 directly interacted with miR-543. MiR-543 mediated the regulatory effects of SNHG14 silencing on BC cell behaviors. Moreover, KLF7 was a direct target of miR-543. Overexpressed miR-543-mediated anti-proliferation, anti-migration, anti-invasion, and pro-apoptosis effects were mediated by KLF7. Furthermore, SNHG14 modulated KFL7 expression through acting as a competing endogenous RNA (ceRNA) of miR-543 in BC cells. CONCLUSION: Our study suggested that SNHG14 knockdown hindered BC progression in vitro at least partly through acting as a ceRNA of miR-543 and modulating KLF7 expression, providing evidence for SNHG14 as a potential target for BC therapy.

The role of miR-543 in human cancerous and noncancerous diseases.

MicroRNA (miRNA) is a noncoding single-stranded RNA molecule that can regulate the posttranscriptional expression level of a gene by binding to the 3'-untranslated region (3'-UTR) of the target messenger RNA. miR-543 is a kind of miRNA, which plays an important role in the occurrence and development of various human cancerous and noncancerous diseases. miR-543 directly or indirectly regulates a large number of downstream target genes and plays an important role in cellular components, biological processes, and molecular functions. In addition, many studies have verified the regulatory mechanism, physiological role, biological function, and prognostic value of miR-543. Therefore, this article reviews the papers published in the past decade and elaborates on the research progress of miR-543 from the aspects of physiology and pathology, especially in cancerous and other noncancerous diseases. In particular, we pay attention to the expression patterns, direct targets, biological functions, related pathways, and prognostic value of miR-543 reported in experimental articles. And by comparing similar research articles, we point out existing controversies in this field to date, so as to facilitate further research in the future.

miR-543 impairs cell proliferation, migration, and invasion in breast cancer by suppressing VCAN.

Breast cancer (BC) continues to plague millions of people worldwide. MicroRNAs have been observed to be closely associated with many cancers and may serve as promising biomarkers for the diagnosis of BC. BC tissue samples were collected from 26 patients, and qRT-PCR and western blotting were performed to evaluate the levels of miR-543 and VCAN. The action of miR-543 and VCAN was determined using CCK-8, BrdU, wound healing, and transwell invasion assays. Luciferase and RNA pull-down assays were used to assess whether miR-543 bound to VCAN. We found that miR-543 inhibited BC cell viability, proliferation, migration, and invasion by repressing the expression of VCAN. VCAN was upregulated in BC tissues and exerted beneficial effects on the development process of BC. Our results highlighted that the miR-543/VCAN axis is a promising diagnostic and prognostic biomarker in clinical applications.

LncRNA SNHG6 promotes breast cancer progression and epithelial-mesenchymal transition via miR-543/LAMC1 axis.

PURPOSE: Breast cancer (BC) is the most prevalent cancer in women with an estimated incidence of 10% and the leading cause of mortality due to its heterogenous property and high metastasis rate. Development of novel therapy is very necessary and requires an understanding of molecular mechanisms. We investigated the function of SNHG6/miR-543/LAMC1 axis in BC. METHODS: Human BC tissues were obtained from diagnosed patients. BC cell lines and normal breast cells were used. QRT-PCR and Western blotting were employed to measure expression levels of SNHG6, miR-543, LAMC1, EMT-related proteins, and PI3K/AKT pathway. Dual-luciferase assay was performed to validate interactions of SNHG6/miR-543 and miR-543/LAMC1. Colony formation assay, flow cytometry, scratch wound healing assay, and transwell assay were utilized to assess the proliferation, apoptosis, migration, and invasion of BC cells. Nude mouse xenograft model was used the evaluate the function of SNHG6/miR-543 in tumor growth in vivo. RESULTS: SNHG6 and LAMC1 were elevated, but miR-543 was reduced in BC tissues and cells. SNHG6 interacted directly with miR-543, while miR-543 targeted LAMC1. Knockdown of SNHG6 suppressed BC cell proliferation, migration, invasion, EMT, and PI3K/AKT pathway, but promoted cell apoptosis, while miR-543 inhibitor or overexpression of LAMC1 reversed those effects. Overexpression of LAMC1 also blocked the effects of miR-543 on BC cell proliferation, migration, invasion, and EMT. Knockdown of SNHG6 restrained BC growth in vivo, while miR-543 inhibitor inhibited that suppression. CONCLUSION: SNHG6 promoted EMT and BC cell proliferation and migration by acting as a miR-543 sponge and disinhibiting LAMC1/PI3K/AKT pathway. SNHG6/miR-543/LAMC1 axis could serve as candidates for the development of therapeutic strategies for BC.

miR-543 in human mesenchymal stem cell-derived exosomes promotes cardiac microvascular endothelial cell angiogenesis after myocardial infarction through COL4A1.

To explore the impact and mechanism of human mesenchymal stem cells (hMSCs) on the angiogenesis of cardiac microvascular endothelial cells (CMECs) after ischemia insult. Exosomes derived from hMSCs (hMSCs-Exo) were identified by Western blotting and labeled by PHK-67. CMECs were isolated from rat myocardial tissues. After hypoxic treatment, CMECs were cultured with hMSCs and exosome inhibitor (GW4869) or transfected with si-COL4A1 + miR-543 inhibitor. CMEC proliferation, migration, invasion, and angiogenesis were examined. Target genes of miR-543 were predicted and then were identified by dual luciferase assay. Myocardial infarction (MI) rat model established by suture occlusion was intravenously injected with hMSCs-Exo. Fluorescence microscope was applied to visualize exosomes in myocardial tissues. Infarction volume and pathologies of myocardial tissues were observed. Ki-67 and miR-543 expressions were detected. The isolated hMSC-Exo expressed TSG101, HSP70, and CD63. Hypoxia-treated CMECs cultured with hMSCs exhibited high proliferation, migration, invasion, and angiogenesis ability, while incubation with exosome inhibitor GW4969 offset the promoting effects of hMSCs on the proliferation, migration, invasion, and angiogenesis of CMECs. hMSCs transfected with miR-543 inhibitor brought CMECs weak viability and angiogenesis ability. CMECs transfected with si-COL4A1 and miR-543 inhibitor showed low proliferation, migration, invasion, and angiogenesis compared to those transfected with si-COL4A1 alone. hMSCs-Exo entered the myocardial tissues of MI rats. Injection of hMSCs-Exo in MI rats diminished infarction size, attenuated MI-induced injuries, and increased Ki-67 expression. hMSCs-Exo facilitates the proliferation, migration, invasion, and angiogenesis of CMECs through transferring miR-543 and downregulating COL4A1 expression.

CircSOS2 promotes cervical squamous cell carcinoma by regulation of proliferation, cell cycle, apoptosis, migration, invasion, and glycolysis by targeting miR-543/FNDC3B axis.

BACKGROUND: Cervical squamous cell carcinoma (SCC) is a common subtype of cervical cancer. Circular RNAs (circRNAs) have been demonstrated as vital regulators in gene regulation and malignant tumor progression. Therefore, the precise role of circular RNA salt overly-sensitive 2 (circSOS2) was investigated in SCC. METHODS: The relative expression levels of circSOS2, microRNA-543 (miR-543), and Fibronectin type III domain containing 3B (FNDC3B) were determined by real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot assays. The correlation between percent survival times of SCC patients and circSOS2 level was presented by Kaplan-Meier Plotter analysis. The cell proliferation was measured by MTT and colony-forming assays. Flow cytometry assay was used to assess apoptosis and cell cycle distribution. The migration and invasion were measured by transwell assay. The glycolysis was analyzed by extracellular acidification rate (ECAR) assay, Glucose Assay Kit, and Lactate Assay Kit. The interaction relationship between miR-543 and circSOS2 or FNDC3B was analyzed by dual-luciferase reporter, RNA immunoprecipitation (RIP), and RNA pull-down assays. A xenograft experiment was established to clarify the functional role of circSOS2 inhibition in viv. RESULTS: CircSOS2 was highly expressed in SCC tissues and cells; besides, its expression level was closely associated with poor prognosis. Loss-of-functional experiments revealed that suppression of circSOS2 repressed proliferation, cell cycle process, migration, invasion, and glycolysis while induced apoptosis in SCC cells, which was overturned by inhibition of miR-543. In addition, miR-543 was downregulated and negatively correlated with circSOS2 expression in SCC tissues. We also found that overexpression of miR-543 impeded proliferation, cell cycle process, migration, invasion, and glycolysis while induced apoptosis in SCC cells by targeting FNDC3B. The silencing of circSOS2 impeded tumorigenesis in vivo. CONCLUSION: CircSOS2 conferred an oncogenic function in SCC by regulation of proliferation, cell cycle, apoptosis, migration, invasion, and glycolysis of SCC cells, which was contributed to its interactions with miR-543 and FNDC3B.

MiR-543 regulates myoblast proliferation and differentiation of C2C12 cells by targeting KLF6.

MicroRNA-543 (miR-543) has been found to play a suppressive role in various human cancers in many studies, whereas the specific functions of miR-543 in muscle development remain poorly understood. Here, we found that the expression of miR-543 was high in skeletal muscle and increased during the differentiation of C2C12 cells. Overexpression of miR-543 repressed C2C12 cell proliferation and promoted differentiation, while knockdown of miR-543 expression produced the opposite results. During myogenesis, we predicted and verified that Krüppel-like factor 6 (KLF6), a suppressor of multiple tumor cells, was a target gene of miR-543. Then, miR-543 was found to specifically target KLF6 and repress its expression. Besides this, knockdown of KLF6 promoted the differentiation but inhibited the proliferation of C2C12 cells. Si-KLF6 can rescue the influence of miR-543 inhibitor on C2C12 cell differentiation. Our results indicate a new regulatory mechanism of miR-543 on KLF6 expression and suggest the possibility of using the miR-543/KLF6 pathway as a potential target for studying myogenesis.

MiR-543 promotes tumorigenesis and angiogenesis in non-small cell lung cancer via modulating metastasis associated protein 1.

OBJECTIVE: This study is aimed to explore the role of miR-543 in non-small cell lung cancer (NSCLC), and verify whether miR-543 targets metastasis associated protein 1 (MTA1) to affect tumorigenesis and angiogenesis in NSCLC. METHODS: Firstly, miR-543 mimic and inhibitor were transfected into A549 cells and H1299 cells. The cells proliferation was tested by MTT and clone formation. The cells apoptosis was analyzed by cytometry. Tube formation assay was used to measure the vascularization of cells. qRT-PCR and Western Blot were used to measure the MTA1 expression. Dual-luciferase assay was used to analyze whether miR-543 targets MTA1. Secondly, MTA1 mimic and inhibitor were transfected into cells to analyze the effect of MTA1 on proliferation and angiogenesis in NSCLC cells. Lastly, the nude mice were used to verify the effect of miR-543 on tumorigenesis and angiogeneisis in NSCLC via modulating MATA1. RESULTS: miR-543 overexpression could apparently promote cells proliferation and angiogeneisis in NSCLC cells. Meanwhile, the MTA1 expression was increased after transfecting miR-543 mimic. Dual luciferase reporter assay revealed MTA1 was a downstream target of miR-543. Further studies showed that inhibition of MTA1 weakened the role of miR-543 overexpression in NSCLC cells. Vivo experiments revealed that miR-543 promoted cells proliferation and angiogenesis in tumor tissues via modulating MTA1. CONCLUSION: miR-543 could target MTA1 to promote tumorigenesis and angiogenesis in NSCLC via targeting MTA1.

LncRNA SNHG6 promotes LMO3 expression by sponging miR-543 in glioma.

Small nucleolar RNA host gene 6 (SNHG6) was a newly discovered long non-coding RNA, which was involved in the occurrence and development of a variety of cancers and was on the rise in human cancers. However, the molecular mechanism of SNHG6 in glioma required further investigation. The levels of SNHG6, microRNA-543 (miR-543) and LIM-only protein 3 (LMO3) were detected in glioma tissues and cells by quantitative real-time polymerase chain reaction. We examined cell proliferation and apoptosis rate by methylthiazolyldiphenyl-tetrazolium bromide and flow cytometry assays, respectively. Transwell assay was used to measure cell migration and invasion. The target relationships were predicted by StarBase v.2.0 and TargetScan and confirmed by dual-luciferase reporter assay. Spearman's test was adopted for expression correlation of SNHG6, miR-543 and LMO3 in tissues. The protein expression level of LMO3 was assessed by western blot. We found that SNHG6 was obviously upregulated in glioma tissues and cells. SNHG6 knockdown significantly repressed glioma cell proliferation, migration and invasion, and induced apoptosis. Additionally, SNHG6 directly targeted miR-543 and their expression was negatively correlated in glioma tissues. And miR-543 targeted LMO3 and their expression was also inversely correlated. We found that silencing LMO3 also inhibited the progression of glioma cells. Importantly, SNHG6 could competitively sponging miR-543 thereby modulating LMO3 in glioma cells. SNHG6 served as an oncogene and played a vital role in glioma development through miR-543/LMO3 axis.

MiR-543 functions as tumor suppressor in ovarian cancer by targeting TWIST1.

MicroRNAs (miRNAs) have been demonstrated to have promoting or inhibiting effects on the tumorigenesis of multiple cancers, including ovarian cancer (OC), by regulating its downstream target genes. In the presented experiment, our aim was to explore the role of miR-543 in OC cell proliferation and invasion. Results of quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot revealed that miR-543 have lower expression levels, while Twist homolog 1 (TWIST1) was expressed with higher levels in OC tissues and cells. Furthermore, the effects of abnormal miR-543 expression in OC cell proliferation and invasion were detected by CCK-8 and Transwell assay. According to luciferase reporter assay results, TWIST1 was identified as a downstream target of miR-543 in OC, and a negative correlation was observed between TWIST1 and miR-543 expression by Spearman's correlation analysis in OC tissues. In addition, TWIST1 may reverse the miR-543 suppression effect on OC cell proliferation and invasion. To sum up, miR-543 may promote OC cell proliferation and invasion by targeting TWIST1.

Linc-PINT acted as a tumor suppressor by sponging miR-543 and miR-576-5p in esophageal cancer.

This manuscript aimed to investigate linc-PINT's role as a tumor suppressor and its downstream microRNAs (miRNAs) in esophageal cancer. Log-rank, Cox, and nomogram were used for survival analysis. Quantitative real-time polymerase chain reaction was used to evaluate the expression. Cell counting kit-8 was used for proliferation tests. As for in vivo experiments, low expression of linc-PINT was associated with better prognosis; besides, the nomogram indicated that linc-PINT, miR-543, and miR-576-5p served well in predicting the survival rate. As for the in vitro experiments, linc-PINT could directly regulate miR-543 and miR-576-5p to inhibit the proliferation of Eca-109 cell line. In conclusion, linc-PINT-miR-543/miR-576-5p pathway could predict the prognosis and provide novel therapeutic targets for esophageal cancer.

Long noncoding RNA SNHG7 inhibits high glucose-induced human retinal endothelial cells angiogenesis by regulating miR-543/SIRT1 axis.

Diabetic retinopathy (DR) is the serious complication of type 2 diabetes mellitus, which could lead to visual impairment. Growing evidence have revealed the involvement of long non-coding RNAs (lncRNAs) in the pathogenesis of DR. Thus, this study was performed to investigate the role of lncRNA SNHG7 (small nucleolar RNA host gene 7) in high glucose (HG)-induced proliferation, migration, and angiogenesis of human retinal endothelial cells (hRECs). We discovered that SNHG7 was decreased in hRECs under HG stimuli. Although SNHG7 had no influence on cell viability, migration and angiogenesis under condition, overexpression of SNHG7 inhibited the HG-induced cell proliferation, migration and angiogenesis, as well as vascular endothelial growth factor (VEGF) expression in HG condition. In terms of mechanism, we found that SNHG7 directly inhibited miR-543, which targeted the 3'-UTR of Silent information regulator T1 (SIRT1) mRNA and subsequently downregulated the VEGF expression in hRECs. Ultimately, upregulation of miR-543 or inhibition of SIRT1 both abrogated the effect of SNHG7 on HG-induced angiogenesis. Collectively, our results suggested that SNHG7 is a potential molecular target for attenuating HG-induced angiogenesis in the DR through regulation of the miR-543-mediated SIRT1/VEGF pathway.

lncRNA HCG11 regulates cell progression by targeting miR-543 and regulating AKT/mTOR pathway in prostate cancer.

Prostate cancer (PCa) is a common cancer worldwide, which mostly occurs in males over the age of 50. Accumulating evidence have determined that long non-coding RNA/microRNA (lncRNA/miRNA) axis plays a critical role in cell progression of cancers, including PCa. However, the pathogenesis of PCa has not been fully indicated. In this study, quantitative real-time polymerase chain reaction was used to detect the expression of HCG11 and miR-543. Western blot was applied to measure the protein expression of proliferating cell nuclear antigen, cleavage-caspase 3 (cle-caspase 3), N-cadherin, E-cadherin, GAPDH, P-AKT, AKT, p-mTOR, and mTOR. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), transwell invasion, and transwell migration assay were used to detect cell proliferation, invasion, and migration, respectively. The function and mechanism of lncRNA HCG11 were confirmed in PCa cell and xenograft mice models. Luciferase assay indicated that miR-543 was a target miRNA of HCG11. Further investigation revealed that overexpression of HCG11 inhibited cell proliferation, invasion, and migration, whereas induced cell apoptosis by regulating miR-543 expression in vitro and in vivo. More than that, lncRNA HCG11 inhibited phosphoinositide-3 kinase/protein kinaseB (PI3K/AKT) signaling pathway to suppress PCa progression. Our data showed the overexpression of HGC11-inhibited PI3K/AKT signaling pathway by downregulating miR-543 expression, resulting in the suppression of cell growth in PCa. This finding proved a new regulatory network in PCa and provided a novel therapeutic target of PCa.

MiR-543 Promotes Migration, Invasion and Epithelial-Mesenchymal Transition of Esophageal Cancer Cells by Targeting Phospholipase A2 Group IVA.

BACKGROUND/AIMS: The aim of this study was to investigate the roles of miR-543 and phospholipase A2 group IVA (PLA2G4A) in cell mobility and the invasiveness cascade in esophageal squamous cell carcinoma (ESCC) and to validate the interactive relationship between miR-543 and PLA2G4A. METHODS: Microarray analysis showed the different expression levels of PLA2G4A in two ESCC cell lines (KYSE30 and KYSE180). The expression levels of miR-543 and PLA2G4A in ESCC tissues were confirmed by qRT-PCR and Western blotting. The targeted relationship between miR-543 and PLA2G4A was studied and verified by a luciferase activity assay. Then, the invasion and metastasis ability of ESCC cell lines transfected with miR-543 mimics, miR-543 inhibitor, or PLA2G4A and miR-543 mimics were analyzed separately by Transwell migration and invasion assays. In addition, the roles of miR-543 and PLA2G4A in the expression of E-cadherin and vimentin were also investigated. RESULTS: PLA2G4A up-regulated the level of E-cadherin and down-regulated the level of vimentin, which curbed ESCC cell mobility and invasion. In ESCC cells, the expression of miR-543 was significantly higher, whereas the expression of PLA2G4A was markedly lower. MiR-543 facilitated ESCC cell mobility and invasion by repressing PLA2G4A. CONCLUSIONS: MiR-543 enhanced the cell mobility and the invasiveness cascade in ESCC cells via the down-regulation of PLA2G4A expression.

MiR-543 Promotes Proliferation and Epithelial-Mesenchymal Transition in Prostate Cancer via Targeting RKIP.

BACKGROUND/AIMS: MicroRNAs (miRNAs, miRs) have emerged as important post-transcriptional regulators in various cancers. miR-543 has been reported to play critical roles in hepatocellular carcinoma and colorectal cancer, however, the role of miR-543 in the pathogenesis of prostate cancer has not been fully understood. METHODS: Expression of miR-543 and Raf Kinase Inhibitory Protein (RKIP) in clinical prostate cancer specimens, two prostate cancer cell lines, namely LNCAP and C4-2B, were determined. The effects of miR-543 on proliferation and metastasis of tumor cells were also investigated with both in vitro and in vivo studies. RESULTS: miR-543 was found to be negatively correlated with RKIP expression in clinical tumor samples and was significantly upregulated in metastatic prostate cancer cell line C4-2B compared with parental LNCAP cells. Further studies identified RKIP as a direct target of miR-543. Overexpression of miR-543 downregulated RKIP expression and promoted the proliferation and metastasis of cancer cells, whereas knockdown of miR-543 increased expression of RKIP and suppressed the proliferation and metastasis of cancer cells in vitro and in vivo. CONCLUSION: Our study demonstrates that miR-543 promotes the proliferation and metastasis of prostate cancer via targeting RKIP.

UBE2T promotes hepatocellular carcinoma cell growth via ubiquitination of p53.

Deregulation of Ubiquitin-conjugating enzyme E2T (UBE2T) contributes to the progression of human cancers. However, its clinical significance and role in hepatocellular carcinoma (HCC) remain unclear. Here, we show that UBE2T is up-regulated in HCC and exerts oncogenic activities via ubiquitination of p53. High UBE2T expression was correlated with higher pathological grade, advanced TNM stage, tumor vascular invasion, and poor overall and disease-free survivals in two independent cohorts containing 827 patients with HCC. UBE2T was further identified as an independent factor for overall survival by multivariate analyses. Luciferase reporter assays confirmed that UBE2T was directly targeted by miR-543 which was down-regulated in HCC. In vitro experiments demonstrated that UBE2T overexpression promoted, whereas UBE2T knockdown inhibited HCC cell growth. Ectopic expression of UBE2T resulted in the decreases of p53, p21 and Noxa. Further studies revealed that UBE2T facilitated the degradation of p53 protein via enhancing its ubiquitination. Collectively, our findings suggest UBE2T serves as a promising prognostic factor for HCC and functions as an oncogene. The newly identified miR-543/UBE2T/p53 axis may represent a new potential therapeutic target for HCC intervention.

Dysregulation of MicroRNA-543 expression in colorectal cancer promotes tumor migration and invasion.

MicroRNAs (miRNAs) have been proven to act as key post-transcriptional regulators of gene expression, involved in the genesis and development of multiple tumor types. However, the expression and roles of miR-543 in colorectal cancer (CRC) remain unknown. Here, we found that miR-543 was constitutively up-regulated in CRC tissues and its over-expression promoted tumor cell migration and invasion. Moreover, we identified PTEN as a direct target of miR-543 using subsequent software analysis and a dual-luciferase reporter assay. In conclusion, data presented here demonstrate that miR-543 acts as a tumor promoter and plays a vital role in CRC metastasis. These findings confirm that miR-543 may potentially serve as a novel therapeutic target for treating CRC. © 2016 Wiley Periodicals, Inc.