miRNA-411 acts as a potential tumor suppressor miRNA via the downregulation of specificity protein 1 in breast cancer

Biological Implications of MicroRNAs as Regulators and Biomarkers of Therapeutic Toxicities in Breast Cancer

Contemporary breast cancer management includes surgical resection combined with a multimodal approach, including chemotherapy, radiotherapy, endocrine therapy, and targeted therapies. Breast cancer treatment is now personalised in accordance with disease and host factors, which has translated to enhanced outcomes for the vast majority of patients. Unfortunately, the treatment of the disease involves patients developing treatment-induced toxicities, with cardiovascular and metabolic side effects having negative implications for long-term quality-of-life metrics. MicroRNAs (miRNAs) are a class of small non-coding ribonucleic acids that are 17 to 25 nucleotides in length, which have utility in modifying genetic expression by working at a post-transcriptional cellular level. miRNAs have involvement in modulating breast cancer development, which is well described, with these biomarkers acting as important regulators of disease, as well as potential diagnostic and therapeutic biomarkers. This review focuses on highlighting the role of miRNAs as regulators and biomarkers of disease, particularly in breast cancer management, with a specific mention of the potential value of miRNAs in predicting treatment-related cardiovascular toxicity.

The antihyperlipidemic drug potassium piperonate impairs the migration and tumorigenesis of breast cancer cells via the upregulation of miR-31

Background

Breast cancer is the second cause of cancer death in women, and tumor metastasis is the primary cause of mortality. Due to the involvement of many regulatory molecules and signaling pathways, the occurrence and development of metastases needs to be further studied. MicroRNAs (miRNAs) are ubiquitously expressed small non-coding RNAs that have been shown to play an important role in the diagnosis and treatment of many diseases, as well as representing an attractive candidate for metastasis control. In this study, we investigated the mechanism of potassium piperonate (GBK) in impairing breast cancer cell invasion and metastasis by targeting miR-31.

Methods

Breast cancer cells, either treated with GBK or left untreated, were assessed for migration and invasion capacities using wound healing and transwell assays. GBK-targeted miRNAs were identified and verified using RT-qPCR. Western blotting was used to validate the changes in expression levels of miR-31-targeted genes. Methylation specific PCR was performed to detect the effect of GBK on the methylation levels of the lncRNA LOC554202 host gene. The synergistic effect of GBK and the chemotherapy drug cisplatin (DDP) on breast cancer cells was verified using cell proliferation, colony formation, and RT-qPCR assays in vitro, and the tumor xenograft model in vivo.

Results

We found that miR-31 was the main target of GBK. GBK treatment affected the epigenetic modification at CpG sites by downregulating DNA methyltransferases. Thus, the CpG-associated methylation levels of lncRNA LOC554202 decreased significantly, and in turn upregulated both miR-31 and its host gene LOC554202 in breast cancer cells. We also observed the significant inhibition of miR-31-targeted genes following GBK treatment, including RHOA, WAVE3, and SATB2, with functions closely related to cancer cell invasion, migration, and proliferation. Furthermore, we revealed that the combination of GBK and DDP had a synergistic effect on inhibiting the proliferation of breast cancer cells in vitro and in vivo, especially in triple negative breast cancer (TNBC).

Conclusions

This study investigated the target of GBK in the inhibition of breast cancer migration and invasion, and the underlying mechanisms involved, providing theoretical support for the development of GBK as an auxiliary drug for clinical treatment.

CircNDST1 Regulates Bovine Myoblasts Proliferation and Differentiation via the miR-411a/Smad4 Axis

Circular RNA (circRNA) is endogenous noncoding RNA found throughout the eukaryotic genome. It regulates several biological activities at the transcription or post-transcription level. However, the underlying function of circRNA in bovine skeletal muscle development remains unknown. Here, we identified a novel circRNA, circNDST1, and investigated its function and mechanism on the proliferation and differentiation of bovine myoblasts. At the molecular and cellular levels, circNDST1 could promote bovine myoblasts proliferation and inhibit differentiation. Mechanistically, circNDST1 is expressed in the cytoplasmic of myoblast and was enriched by protein Ago2. circNDST1 acts as a competing endogenous RNA that sponges miR-411a and alleviates the inhibitory effect on its target gene, Smad4. miR-411a and Smad4 were also involved in regulating bovine myoblast proliferation and differentiation. These findings suggest that circNDST1 functions as a competing endogenous RNA and regulates bovine myoblast proliferation and differentiation through the miR-411a/Smad4 axis.

Dysregulation of miR-411 in cancer: Causative factor for pathogenesis, diagnosis and prognosis

MiRNA accounts for 1-3% of genes but regulates more than 30% of gene expression in humans. This article analyzes the current deficiencies and challenges of miR-411 research and looks forward to the prospects of miR-411 in cancer. MiR-411 is a non-coding RNA located on chromosome 14. MiR-411 is abnormally expressed in a variety of cancers. The dysregulation of miR-411 can affect cancer cell proliferation, invasion, migration, apoptosis, colony formation, etc. miR-411 can be regulated by different lncRNAs and circRNAs. By targeting multiple genes, miR-411 participates in the activation of the MAPK signaling pathway, PI3K/AKT/mTOR signaling pathway, p53 signaling pathway, Ras signaling pathway, NF-κB signaling pathway, and Wnt/β-catenin signaling pathway. The expression of miR-411 is related to the diagnosis, prognosis, and sensitivity of drugs in cancer patients. In conclusion, this work outlines the molecular mechanisms and cellular functions of aberrant expression of miR-411 and its target genes in cancer to reveal its potential value in diagnosis, prognosis, and drug sensitivity.

Deciphering Key Genes and miRNAs Associated With Hepatocellular Carcinoma via Network-Based Approach

Hepatocellular carcinoma (HCC)is a common type of liver cancer and has a high mortality world-widely. The diagnosis, prognoses, and therapeutics are very poor due to the unclear molecular mechanism of progression of the disease. To unveil the molecular mechanism of progression of HCC, we extract a large sample of mRNA expression levels from the GEO database where a total of 167 samples were used for study, and out of them, 115 samples were from HCC tumor tissue. This study aims to investigate the module of differentially expressed genes (DEGs)which are co-expressed only in HCC sample data but not in normal tissue samples. Thereafter, we identified the highly significant module of significant co-expressed genes and formed a PPI network for these genes. There were only six genes (namely, MSH3, DMC1, ALPP, IL10, ZNF223, and HSD17B7)obtained after analysis of the PPI network. Out of six only MSH3, DMC1, HSD17B7, and IL10 were found enriched in GO Term & Pathway enrichment analysis and these candidate genes were mainly involved in cellular process, metabolic and catalytic activity, which promote the development & progression of HCC. Lastly, the composite 3-node FFL reveals the driver miRNAs and TFs associated with our key genes.

The alerting expression of microRNA-411 predicts clinical prognosis and regulates tumor progression of glioblastoma

Glioblastoma is a malignant intracranial tumor with indispensable growth. Identification of biomarkers associated with the progression of tumors could benefit the clinical therapy of and improve patient’s survival. miR-411 has been reported to play a role in other cancers, while its function in glioblastoma has been explored in the present study. The expression of miR-411 was evaluated in glioblastoma tissues (collected from 108 glioblastoma patients) and cells by polymerase chain reaction. The clinical significance of miR-411 was estimated with a series of statistical analyses. The biological function of miR-411 in the cellular processes of glioblastoma was assessed by cell counting kit 8 and Transwell assay. The expression of miR-411 was significantly reduced in glioblastoma, which was associated with the Karnofsky Performance Score (KPS) and Isocitrate dehydrogenase 1 (IDH1) status of patients. miR-411 was identified as an independent prognostic indicator that correlated with the poor prognosis of patients. miR-411 suppressed the growth, migration, and invasion of glioblastoma cells via modulating signal transducer and activator of transcription 3 (STAT3). miR-411 participated in the development of glioblastoma and function as a prognostic biomarker. miR-411 functions as a tumor suppressor, which provides a novel potential therapeutic target for glioblastoma.

Emerging Evidence of the Functional Impact of the miR379/miR656 Cluster (C14MC) in Breast Cancer

Many microRNAs exist in clusters that share comparable sequence homology and may target genes in a common pathway. The miR-379/miR-656 (C14MC) cluster is imprinted in the DLK1-Dio3 region of 14q32.3 and contains 42 miRNAs. It plays a functional role in numerous biological pathways including vascular remodeling and early development. With many C14MC miRNAs highlighted as potential tumor suppressors in a variety of cancers, the role of this cluster in breast cancer (BC) has garnered increased attention in recent years. This review focuses on C14MC in BC, providing an overview of the constituent miRNAs and addressing each in terms of functional impact, potential target genes/pathways, and, where relevant, biomarker capacity. Studies have revealed the regulation of key factors in disease progression and metastasis including tyrosine kinase pathways and factors critical to epithelial–mesenchymal transition (EMT). This has potentially important clinical implications, with EMT playing a critical role in BC metastasis and tyrosine kinase inhibitors (TKIs) in widespread use for the treatment of BC. While the majority of studies have reported tumor-suppressing roles for these miRNAs, some have highlighted their potential as oncomiRs. Understanding the collective contribution of miRNAs within C14MC to BC may support improved understanding of disease etiology and present novel approaches to targeted therapy.

miRNA-128 modulates bone neoplasms cells proliferation and migration through the WNT/β-catenin and EMT signal pathways

BACKGROUND

Bone neoplasms present poor prognosis due to recurrence and metastasis. Although the role microRNAs (miRNAs) in inhibiting growth and metastasis of bone neoplasms has been investigated, the underlying potential molecular mechanisms mediated by miRNA-128 (miR-218) for the invasiveness of bone neoplasms cells are still not completely understood. The purpose of this study was to identify the regulatory mechanisms of miR-218 in bone neoplasms cells.

METHODS

Western blotting, quantitative reverse transcription-polymerase chain reaction (qRT-PCR), Counting Kit-8 assay, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining, luciferase activity assay immunofluorescence, and immunohistochemistry were used to analyze the regulatory effects of miR-218 on bone neoplasms cells.

RESULTS

Here, the results showed that transfection of miR-128 suppressed bone neoplasms cells proliferation, migration, and invasion. Genetic knockdown of miR-128 in bone neoplasms cells suppressed the activation of the Wnt/β-catenin and epithelial-mesenchymal transition (EMT) signaling pathways. Activation of Wnt or EMT blocked miR-128-inhibited cells proliferation and migration in bone neoplasms cells. Exogenously introduced miR-128 markedly inhibited tumor regeneration in bone neoplasms xenograft models.

CONCLUSIONS

These results define a tumor-regulated function for miR-128 in bone neoplasms by down-regulation of the Wnt/β-catenin and EMT signal pathways, which provided a potential target for bone neoplasms gene therapy.

Pan-cancer analysis of somatic mutations in miRNA genes

Background

miRNAs are considered important players in oncogenesis, serving either as oncomiRs or suppressormiRs. Although the accumulation of somatic alterations is an intrinsic aspect of cancer development and many important cancer-driving mutations have been identified in protein-coding genes, the area of functional somatic mutations in miRNA genes is heavily understudied.

Methods

Here, based on the analysis of large genomic datasets, mostly the whole-exome sequencing of over 10,000 cancer/normal sample pairs deposited within the TCGA repository, we undertook an analysis of somatic mutations in miRNA genes.

Findings

We identified and characterized over 10,000 somatic mutations and showed that some of the miRNA genes are overmutated in Pan-Cancer and/or specific cancers. Nonrandom occurrence of the identified mutations was confirmed by a strong association of overmutated miRNA genes with KEGG pathways, most of which were related to specific cancer types or cancer-related processes. Additionally, we showed that mutations in some of the overmutated genes correlate with miRNA expression, cancer staging, and patient survival.

Interpretation

Our study is the first comprehensive Pan-Cancer study of cancer somatic mutations in miRNA genes. It may help to understand the consequences of mutations in miRNA genes and the identification of miRNA functional mutations. The results may also be the first step (form the basis and provide the resources) in the development of computational and/or statistical approaches/tools dedicated to the identification of cancer-driver miRNA genes.

Funding

This work was supported by research grants from the Polish National Science Centre 2016/22/A/NZ2/00184 and 2015/17/N/NZ3/03629.

Integrative mRNA/miRNA expression analysis in healing human gingiva

BACKGROUND

MicroRNAs (miRNAs) are implicated in the epigenetic regulation of complex biological processes. Their possible role in human oral wound healing, a process that differs from cutaneous wound healing by being faster and typically scar-free, has been unexplored. This report presents the miRNA expression profile of experimental human oral wounds and an integrative analysis of mRNA/miRNA expression.

METHODS

Nine healthy volunteers provided standardized normal and 5-day healing palatal biopsies, used for next generation miRNA and mRNA sequencing analysis, correlation and network analysis, real-time PCR (qPCR) and immunohistochemistry.

RESULTS

On average, 169 significantly regulated precursor miRNAs were detected, including 21 novel miRNAs, selectively confirmed by PCR. Hsa-miR-223-3p and hsa-miR-124-3p were, respectively, the most up- and downregulated miRNAs in healing gingiva. Hsa-miR-124-3p had the most predicted mRNA target interactions, with angiogenesis-related genes the most enriched. Correlation analysis showed the highest correlation between hsa-miR-181a-3p and SERPINB1; hsa-miR-223-5p and SLC2A3; hsa-miR-1301 and MS4A7. In addition, SERPINB1 mRNA had the most associations with differentially regulated miRNAs. IL33 was the only cytokine significantly correlated with miRNAs (ρ >  0.95). qPCR and immunohistochemistry verified the significant upregulation of SERPINB1 and IL33 in healing gingiva.

CONCLUSIONS

This study is the first to report on the miRNome of healing human gingiva and to provide an integrative analysis of miRNA/mRNA expression during human oral wound healing; the results offer novel insights into the participating molecular mechanisms and raise the possibility of SERPINB1 and IL-33 as potential wound healing therapeutic targets.

Blocking circ_0000520 Suppressed Breast Cancer Cell Growth, Migration and Invasion Partially via miR-1296/SP1 Axis Both in vitro and in vivo

Background

Breast cancer (BCa) is an overwhelming malignant tumor mainly in women globally. Circular RNAs (circRNAs) are a special type of noncoding RNAs involved in competing endogenous RNA (ceRNA) network, a classic molecular mechanism of the tumorigenesis of human cancers, including BCa. Here, we intended to explore the role and mechanism of hsa_circ_0000520 (circ_0000520) in BCa cells.

Methods

Expression of circ_0000520, miRNA-1296-5p (miR-1296) and specificity protein 1 (SP1) was measured by real time-quantitative PCR and Western blotting. Cell growth was measured by cell counting kit-8, colony formation assay and flow cytometry method. Cell migration and invasion were assessed by transwell assays and Western blotting. Tumor growth was determined by xenograft models. The direct interaction among circ_0000520, miR-1296 and SP1 was confirmed by dual-luciferase reporter assay and RNA pull-down assay.

Results

circ_0000520 was upregulated in BCa tumors and cell lines (T47D, MCF7, MDA-MB-231, BT549, and SKBR3), and circ_0000520 high expression was associated with poor overall survival. Blocking circ_0000520 suppressed cell viability, colony formation, migration and invasion, but promoted cell cycle arrest and apoptosis rate in MDA-MB-231 and MCF7 cells. circ_0000520 could directly regulate miR-1296 expression, and SP1 was a novel target for miR-1296. Moreover, the anti-tumor role of circ_0000520 silencing was abrogated by miR-1296 downregulation or SP1 restoration. Notably, tumor growth of MDA-MB-231 cells in mice was restrained by circ_0000520 deletion.

Conclusion

circ_0000520 knockdown could suppress cell growth, migration and invasion both in vitro and in vivo through regulating miR-1296/SP1 pathway.

hsa-microRNA-411-5p regulates proliferation, migration and invasion by targeting the hyaluronan mediated motility receptor in ovarian cancer

The mortality rate of ovarian cancer is the highest out of all gynecological malignancies worldwide. Therefore, it is important to understand the mechanisms of ovarian cancer, identify new biomarkers and develop targeted drugs. The role and molecular mechanisms of hsa-microRNA (miR)-411-5p in ovarian cancer have not been fully elucidated. The present study investigated the ovarian cancer cell lines OVCAR-8 and SKOV3. After transfection with miRNA mimics, cell proliferation was monitored by a proliferation assay. Furthermore, cell migration was measured by a cell wound healing assay and cell invasion was measured by Matrigel invasion assays. A miRNA luciferase reporter assay was used to analyze the relationship between miRNAs and the target gene HMMR, which was then further evaluated by gene differential analysis. In the current study, hsa-mir-411-5p was identified as a miRNA regulator of the hyaluronan mediated motility receptor, which negatively regulated the activity of ERK1/2 and ultimately inhibited ovarian cancer cell proliferation and motility. Although hsa-mir-411-5p may have different roles in other types of cancer, the present study suggested that miR-411-5p functions as a negative tumor regulator in ovarian cancer cells, displaying the potential of miR-411-5p as a biomarker for ovarian cancer.

Prognostic and predictive roles of microRNA‑411 and its target STK17A in evaluating radiotherapy efficacy and their effects on cell migration and invasion via the p53 signaling pathway in cervical cancer

Cervical cancer is one of the most common gynecological malignancies worldwide. However, the pathogenesis of cervical cancer remains to be fully elucidated. Increasing evidence shows that microRNAs (miRNAs) may be involved in the pathogenesis of cervical cancer. The present study tested the hypothesis that the overexpression of miRNA (miR)-411 may delay, whereas the overexpression of serine/threonine kinase 17a (STK17A) may contribute to, cervical cancer development and progression through the p53 pathway. Cervical cancer tissues and adjacent normal tissues were obtained from 141 patients with cervical cancer following radiotherapy, with efficacy evaluated. The receiver operating characteristic curve was plotted to show the value of miR-411 and STK17A in predicting the efficacy of radiotherapy. Cox's proportional hazards regression model was utilized for multivariate analysis. A series of inhibitors, mimics or small interfering RNAs against STK17A were introduced to validate the regulatory mechanism of miR-411 in governing STK17A, determined with a luciferase reporter gene assay. The expression of miR-411 and STK17A, and the status of the p53 signaling pathway were evaluated. The colony forming ability, proliferation, migration, invasion and apoptosis of CaSki cells were assessed using a colony formation assay, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Transwell assay and flow cytometry, respectively. miR-411 was upregulated but STK17A was reciprocal in cervical tissues. The overexpression of miR-411 and low expression of STK17A were correlated with high efficacy of radiotherapy. miR-411 and STK17A had predictive value for the efficacy of radiotherapy; miR-411 was the protective factor and STK17A was a risk factor for prognosis of cervical cancer. Increasing miR-411 activated the p53 signaling pathway and promoted cell apoptosis, but inhibited cell proliferation, invasion and migration. STK17A, an miR-411 target, increased following miR-411 over-expression, whereas the p53 signaling pathway was activated following STK17A inhibition. It was observed that the effect of miR-411 inhibition was lost following STK17A silencing. These findings indicate that the miR-411-mediated direct suppression of STK17A induces apoptosis and suppresses the proliferation, migration and invasion of human cervical cancer cells via the p53 signaling pathway. Additionally, miR-411 and STK17A have predictive value for the efficacy of radiotherapy.

Down-Regulation of Circular RNA_000926 Attenuates Renal Cell Carcinoma Progression through miRNA-411-Dependent CDH2 Inhibition

Many studies have recognized that circular RNAs (circRNAs) can be promising targets for renal cell carcinoma (RCC) by acting as competing endogenous RNAs for miRNAs. This study intends to uncover the implication of a novel circRNA, circ_000926 in RCC, and how it affects tumorigenesis. Microarray-based circRNA/gene expression profiling of RCC was used to identify differentially expressed circRNAs/genes in RCC and normal tissues. miRNAs targeting the screened circRNAs/genes were predicted online, followed by analyzing circ_000926 expression in RCC. The crosstalk among circ_000926, miRNA-411 (miR-411), and CDH2 was then validated. The expression of circ_000926, miR-411, and cadherin 2 (CDH2) was up-regulated or down-regulated in RCC cells to unearth their effects on the biological behaviors of RCC cells. circ_000926 was highly expressed in RCC tissues and cell lines, whereas CDH2 was verified to be a target of miR-411. As a competing endogenous RNA, circ_000926 could directly bind to miR-411 to up-regulate CDH2. Down-regulation of circ_000926 resulted in inhibited growth, migration, and invasion abilities of RCC cells, as well as suppressed epithelial-mesenchymal transition and tumor growth. However, the inhibition of miR-411 or elevation of CDH2 reversed the antitumor effects induced by silencing circ_000926. Down-regulation of circ_000926 exerts an inhibitory effect on RCC progression through miR-411-dependent CDH2 inhibition, highlighting a potential target for RCC treatment.

SNHG8 is upregulated in esophageal squamous cell carcinoma and directly sponges microRNA-411 to increase oncogenicity by upregulating KPNA2

Background

The long noncoding RNA, small nucleolar RNA host gene 8 (SNHG8), is upregulated in multiple human cancer types. However, whether SNHG8 is aberrantly expressed in esophageal squamous cell carcinoma (ESCC) and its biological functions have yet to be elucidated. Thus, we aimed to determine the expression status of SNHG8 in ESCC, explore the effects of SNHG8 on the oncogenicity of ESCC, and investigate the potential underlying mechanisms.

Methods

SNHG8 expression in ESCC tissues and cell lines was determined via reverse-transcription quantitative polymerase chain reaction. The actions of SNHG8 on the malignant characteristics of ESCC were explored using CCK-8 assay, flow-cytometric analysis, Transwell migration and invasion assays, and tumor xenografts in nude mice.

Results

SNHG8 expression was significantly higher in ESCC tissues and cell lines. High SNHG8 expression was revealed to closely correlate with primary tumor invasion depth, lymph node metastases, TNM stage, and worse overall survival among patients with ESCC. Functional investigation showed that ablation of SNHG8 notably restricted ESCC cell proliferation, migration, and invasion while inducing apoptosis in vitro and hindered tumor growth in vivo. In the meantime, SNHG8 acted as a molecular sponge of microRNA-411 (miR-411) in ESCC. Furthermore, miR-411 exerted a tumor-suppressive effect on ESCC cells, and karyopherin alpha 2 (KPNA2) turned out to be a direct target gene of miR-411. Restoring KPNA2 expression neutralized the inhibitory effects of miR-411 overexpression on the malignant behaviors of ESCC cells. Moreover, silencing of miR-411 abrogated the influence of SNHG8 downregulation in ESCC cells.

Conclusion

SNHG8 may play oncogenic roles in the malignancy of ESCC by sponging miR-411 to increase KPNA2 expression. The SNHG8–miR-411–KPNA2 pathway may be a novel target for the treatment of patients with ESCC and offer potential biomarkers for the diagnosis and prognosis of ESCC.

Long noncoding RNA CDKN2B-AS1 interacts with miR-411-3p to regulate ovarian cancer in vitro and in vivo through HIF-1a/VEGF/P38 pathway

Ovarian cancer (OC) is one of the most prevalent cancers with high fatality rate. In the present study, RT-PCR showed that the mRNA level of CDKN2B-AS1 was significantly upregulated while the miR-411-3p was downregulated in OC cell lines. In addition, the Sh-CDKN2B-AS1 resulted in the suppression of cell growth, invasion, migration and promotion of apoptosis, and miR-411-3p showed reversed results. Further studies demonstrated that CDKN2B-AS1 could directly interact with miR-411-3p, and that there was an inverse correlation between miR-411-3p and CDKN2B-AS1. Moreover, the in vivo experiments further demonstrated that Sh-CDKN2B-AS1 could inhibit the tumor growth. In addition, we examined the effect of CDKN2B-AS1 and miR-411-3p on HIF1a/VEGF/P38 axis. Consequently, Sh-CDKN2B-AS1 could suppress this pathway. In summary, our study demonstrated that the CDKN2B-AS1 interacted with miR-411-3p contributing to carcinogenesis in OC. Meanwhile, Sh-CDKN2B-AS1 showed anti-cancer role by promoting apoptosis and inhibiting cell growth, invasion and migration. Collectively, CDKN2B-AS1 modulated these activities possibly though miR-411-3p/HIF1a/VEGF/P38 pathway.

MicroRNA-411 Inhibits Cervical Cancer Progression by Directly Targeting STAT3

Cervical cancer is the third most common gynecological cancer and the fourth leading cause of cancer-related deaths in women around the world. Substantial evidence has demonstrated that microRNA (miRNA) expression is disordered in many malignant tumors. The dysregulation of miRNAs has been suggested to be involved in the tumorigenesis and tumor development of cervical cancer. Therefore, identification of miRNAs and their biological roles and targets involved in tumor pathology would provide valuable insight into the diagnosis and treatment of patients with cervical cancer. MicroRNA-411 (miR-411) has been reported to play an important role in several types of human cancer. However, the expression level, role, and underlying molecular mechanisms of miR-411 in cervical cancer remain unclear. Therefore, the objectives of this study were to investigate the expression pattern and clinical significance of miR-411 in cervical cancer and to evaluate its role and underlying mechanisms in this disease. In this study, we confirmed that the expression of miR-411 was significantly downregulated in both cervical cancer tissues and cell lines. Low expression of miR-411 was associated with tumor size, FIGO stage, lymph node metastasis, and distant metastasis. Additionally, miR-411 overexpression inhibited cell proliferation and invasion in cervical cancer. Furthermore, signal transducer and activator of transcription 3 (STAT3) was identified as a direct target of miR-411 in this disease. In clinical samples, miR-411 expression levels were inversely correlated with STAT3, which was significantly upregulated in cervical cancer. Restored STAT3 expression abolished the tumor-suppressing effects of miR-411 overexpression on the proliferation and invasion of cervical cancer cells. In conclusion, our data demonstrated that miR-411 inhibited cervical cancer progression by directly targeting STAT3 and may represent a novel potential therapeutic target and prognostic marker for patients with this disease.

Oncogenic microRNA-411 promotes lung carcinogenesis by directly targeting suppressor genes SPRY4 and TXNIP

Lung cancer is one of the most common malignant diseases globally, composed of non-small cell lung cancer (NSCLC, 85%) and small cell lung cancer (SCLC, 15%). MicroRNAs (miRNAs) are single-stranded noncoding RNAs having important roles in lung cancer development. miR-411-5p/3p were reported to be increased significantly in human NSCLC tissues and cell lines. Moreover, miR-411-5p/3p overexpression could accelerate cell proliferation and migration, and impede cell apoptosis in NSCLC cell lines. Mechanically, SPRY4 is confirmed a direct target of miR-411-5p/3p. Furthermore, our findings showed that miR-411-5p/3p promoted lung tumor growth in vivo, decreased SPRY4 expression dramatically, and induced EGFR, AKT signaling activation, as well as epithelial–mesenchymal transition (EMT) simultaneously in tumor tissues. In addition, we showed that miR-411-5p also targeted tumor suppressor TXNIP, involved in regulating positively cell cycle progress in SPC-A1 cells rather than in H1299. Whether cell specificity of low TXNIP mRNA level in H1299 is responsible for the different response to cell cycle between H1299 and SPC-A1 would need further explorations. Collectively, these results suggest that miR-411-5p/3p are required for NSCLC development by suppressing SPRY4 and TXNIP; thus, the miR-411-SPRY4-AKT axis might act as a promising target for lung cancer therapy clinically.

MicroRNA-30e promotes hepatocyte proliferation and inhibits apoptosis in cecal ligation and puncture-induced sepsis through the JAK/STAT signaling pathway by binding to FOSL2

INTRODUCTION

Hepatocyte proliferation and apoptosis are critical cellular behaviors in rat liver as a result of a liver injury. Herein, we performed this study in order to evaluate the role of miR-30e and its target Fos-Related Antigen-2 (FOSL2) in septic rats through the JAK/STAT signaling pathway.

METHODS

Rat models of sepsis were induced by cecal ligation and puncture. Enzyme-linked immunosorbent assay (ELISA) was performed to access serum levels of lipopolysaccharide (LPS), inflammatory factors, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) to confirm the successful establishment of the model. The hepatocytes were subject to miR-30e mimics, miR-30e inhibitors or siRNA-FOSL2. The expressions of miR-30e, FOSL2, apoptosis- and, JAK/STAT signaling pathway-related genes in liver tissues and hepatocytes were determined by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot analysis. MTT assay and flow cytometry were performed to evaluate hepatocyte viability and apoptosis, respectively.

RESULTS

The results obtained revealed that in the septic rats, serum levels of inflammatory factors, LPS, ALT and AST, as well as the expression of FOSL2 were elevated and the JAK/STAT signaling pathway was activated, while there was a reduction in the expression of miR-30e. An initial bioinformatics prediction followed by a confirmatory dual-luciferase reporter assay determined that miR-30e targeted and negatively regulated FOSL2 expression. MiR-30e inhibited the activation of JSK2/STAT3 signaling pathway by reducing FOSL2 expression, while miR-30e enhanced hepatocyte proliferation and decreased hepatocyte cell apoptosis in septic rats.

CONCLUSION

These findings indicated that miR-30e may serve as an independent therapeutic target for sepsis, due to its ability to inhibit apoptosis and induce proliferation of hepatocytes by targeted inhibition of FOSL2 through the JAK/STAT signaling pathway.

MiR-150-3p targets SP1 and suppresses the growth of glioma cells

Glioma has been considered as one of the most prevalent and common malignancy of the nervous system; however, the underlying mechanisms that are responsible for the occurrence and development of glioma still remain largely unknown. Amounting evidence highlights the critical regulatory function of miRNAs in carcinogenesis. Here, we showed that the expression of miR-150-3p was significantly decreased in glioma tissues and cell lines. Suppressed expression of miR-150-3p was associated with the lymph node metastasis of the glioma patients. Overexpression of miR-150-3p significantly inhibited the proliferation of glioma cells. Molecular study uncovered that the transcription factor specificity protein 1 (SP1) was identified as one of the targets of miR-150-3p Highly expressed miR-150-3p in glioma cells significantly decreased both the mRNA and protein levels of SP1. Consistently, the abundance of phosphatase and tension homolog deleted on chromosome ten (PTEN), a negative downstream target of SP1, was increased with the ectopic miR-150-3p Collectively, these results suggested that miR-150-3p suppressed the growth of glioma cells partially via regulating SP1 and possibly PTEN.

MiR-144 suppresses proliferation, invasion, and migration of breast cancer cells through inhibiting CEP55

OBJECTIVE

The study aimed to investigate the molecular mechanism of miR-144 and CEP55 as well as the influence of their interaction on the cell proliferation, migration, invasion, cell cycle and cell apoptosis in breast cancer.

METHODS

In this study, The Cancer Genome Atlas (TCGA, https://tcga-data.nci.nih.gov/ ) database was used for microarray analysis. The expressions of miR-144 and CEP55 in 40 adjacent tissues and 36 tumor tissues were examined by western blot, qRT-PCR and immunohistochemistry. The target relationship between miR-144 and CEP55 was predicted and confirmed by TargetScan and luciferase reporter assay. The cell proliferation, cell cycle and cell apoptosis in different groups were detected by MTT and flow cytometry assays, while wound healing and transwell assays were used for the cell migration and invasion tests. The regulatory effects of miR-144 and CEP55 on breast tumor were verified through nude mouse model in vivo experiment.

RESULTS

MiR-144 was down-regulated in breast cancerous tissues and cells, whereas CEP55 expression was up-regulated in breast cancerous tissues. Moreover, there existed a target relationship between miR-144 and CEP55 and negative correlation on their expressions. MiR-144 could down-regulate CEP55 expression, thereby inhibiting proliferation, invasion, migration, retarding cell cycle and accelerating cell apoptosis. MiR-144 could inhibit cell progression through down-regulating CEP55 in vivo.

CONCLUSION

MiR-144 suppressed cell proliferation, migration, invasion and induced cell cycle arrest and cell apoptosis by repressing CEP55. This might provide a promising therapy for clinical treatment.

MicroRNA-411 promoted the osteosarcoma progression by suppressing MTSS1 expression

MicroRNAs (miRNAs) play crucial roles in the progression of different tumors. In our study, we investigated the expression and roles of miR-411 in human osteosarcoma. In this study, we first confirmed that the miR-411 expression was higher in the serum of patients with osteosarcoma than in the serum of healthy volunteers. In addition, we found that the miR-411 expression was upregulated in the osteosarcoma tissues compared to that in the matched normal bone tissues. We also demonstrated that the miR-411 expression was upregulated in the four osteosarcoma cell lines. Elevated expression of miR-411 promoted osteosarcoma cell proliferation and migration. Moreover, we identified that metastasis suppressor protein 1 (MTSS1) was a direct target gene of miR-411 in the osteosarcoma cell. We also demonstrated that the MTSS1 expression was downregulated in the osteosarcoma tissues compared to that in the matched normal bone tissues. In addition, MTSS1 expression level was inversely correlated with miR-411 expression in the osteosarcoma tissues. Furthermore, elevated expression of miR-411 enhanced the osteosarcoma cell proliferation and migration through inhibiting the MTSS1 expression. These data suggested that miR-411 played as oncogene in the osteosarcoma partly by inhibiting the MTSS1 expression.

MicroRNA-411 Downregulation Enhances Tumor Growth by Upregulating MLLT11 Expression in Human Bladder Cancer

Although several previous studies have reported the implication of various microRNAs (miRNAs) in regulation of human bladder cancer (BC) development, alterations and function of many miRNAs in bladder cancer growth are not explored yet at present. Here, we screened 1,900 known miRNAs and first discovered that miR-411 was one of the major miRNAs, which was down-regulated in n-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN)-induced BCs. This miR-411 down-regulation was also observed in human BC tissues and cell lines. The results from evaluating the relationship between miR-411 and patient survival in BC using the TCGA (The Cancer Genome Atlas) database indicated that miR-411 was positively correlated with DFS (disease-free survival). Our studies also showed that miR-411 inhibited tumor growth of human BC cells in a xenograft animal model. Mechanistic studies revealed that overexpression of miR-411 repressed the expression of ALL1-fused gene from the chromosome 1q (AF1q) (MLLT11) by binding to the 3′ untranslated region (UTR) of mllt11 mRNA and in turn induced p21 expression and caused cell cycle arrest at the G2/M phase, further inhibiting BC tumor growth. Collectively, our results improve our understanding of the role of miR-411 in BC tumor growth and suggest miR-411 and MLLT11 as potential new targets for the treatment of BC patients.

MicroRNA‑3666 inhibits breast cancer cell proliferation by targeting sirtuin 7

The abnormal expression of microRNAs (miRNAs) is associated with cancer initiation and progression. miRNAs functioning as oncogenes or tumor suppressors represent novel biomarkers for cancer diagnosis, prognosis, and serve as therapeutic tools. MiR‑3666 has been reported as a tumor suppressor in various types of cancer; however, its role in breast cancer remains unknown. In the current study, the aim was to investigate the potential role of miR‑3666 in breast cancer. It was identified that miR‑3666 was decreased in breast cancer cell lines and that the overexpression of miR‑3666 inhibited breast cancer cell proliferation. Furthermore, miR‑3666 promotes cell apoptosis of breast cancer cells. Bioinformatics analysis and dual‑luciferase reporter assay demonstrated that miR‑3666 targeted the 3'‑untranslated region of sirtuin 7 (SIRT7) which was recognized as an oncogene. Overexpression of miR‑3666 decreased SIRT7 expression levels, and knockdown of SIRT7 suppressed proliferation and promoted apoptosis of breast cancer cells. A rescue assay demonstrated that the restoration of SIRT7 expression markedly reversed the miR‑3666‑induced anti‑tumor effects. Thus, the current study indicates that miR‑3666 suppresses breast cancer cell proliferation by targeting SIRT7, and propose miR‑3666 as a potential candidate for breast cancer therapy.

Hsa-miR-599 suppresses the migration and invasion by targeting BRD4 in breast cancer

Breast cancer is the second leading cause of cancer-associated mortality in females in the USA. Hsa-miR-599 was demonstrated to function as a tumour suppressor during cancer progression. However, the function and mechanism of the hsa-miR-599 in human breast cancer remain elusive. Thus, the aim of the present study was to investigate the potential role of hsa-miR-599 in breast cancer biology. The expression levels of hsa-miR-599 in 40 pairs of surgical specimens and human breast cancer cell lines were detected using quantitative polymerase chain reaction analysis. The overexpression of hsa-miR-599 was established by transfecting mimics into the MCF-7 and MDA-MB-231 cell lines. Cell counting kit-8, colony formation and transwell assays were used to investigate the potential function of hsa-miR-599 in MCF-7 and MDA-MB-231 cell lines. Luciferase assays combined with western blot analysis was performed to validate the regulation of a putative target of hsa-miR-599. The results demonstrated that hsa-miR-599 was downregulated in the breast cancer tissues and breast cancer cell lines. Overexpression of hsa-miR-599 was revealed to inhibit the viability and proliferation of cell in vitro and tumour growth in vivo. The results of the luciferase assay indicate that bromodomain containing 4 (BRD4) is a direct target of hsa-miR-599. Furthermore, the xenograft mouse model demonstrated that overexpressed hsa-miR-599 reduced BRD4 expression. These results suggest that hsa-miR-599 serves as an oncosuppressive microRNA that impairs breast cancer tumorigenesis and progression by directly targeting BRD4. Furthermore, increased BRD4 expression partially reversed the suppressive effect of hsa-miR-599. In conclusion, the results of the present study demonstrated that hsa-miR-599 suppressed breast cancer progression by downregulating BRD4. The overexpression of hsa-miR-599 may be considered as a novel therapeutic target for the treatment of patients with breast cancer.