MiR-184 Retarded the Proliferation, Invasiveness and Migration of Glioblastoma Cells by Repressing Stanniocalcin-2

Molecular mechanisms of microRNAs in glioblastoma pathogenesis

Glioblastoma (GBM) is human's most prevalent and severe brain cancer. Epigenetic regulators, micro(mi)RNAs, significantly impact cellular health and disease because of their wide range of targets and functions. The "epigenetic symphony" in which miRNAs perform is responsible for orchestrating the transcription of genetic information. The discovery of regulatory miRNA activities in GBM biology has shown that various miRNAs play a vital role in disease onset and development. Here, we summarize our current understanding of the current state-of-the-art and latest findings regarding the interactions between miRNAs and molecular mechanisms commonly associated with GBM pathogenesis. Moreover, by literature review and reconstruction of the GBM gene regulatory network, we uncovered the connection between miRNAs and critical signaling pathways such as cell proliferation, invasion, and cell death, which provides promising hints for identifying potential therapeutic targets for the treatment of GBM. In addition, the role of miRNAs in GBM patient survival was investigated. The present review, which contains new analyses of the previous literature, may lead to new avenues to explore in the future for the development of multitargeted miRNA-based therapies for GBM.

Stanniocalcin 2 (STC2): a universal tumour biomarker and a potential therapeutical target

Stanniocalcin 2 (STC2) is a glycoprotein which is expressed in a broad spectrum of tumour cells and tumour tissues derived from human breast, colorectum, stomach, esophagus, prostate, kidney, liver, bone, ovary, lung and so forth. The expression of STC2 is regulated at both transcriptional and post-transcriptional levels; particularly, STC2 is significantly stimulated under various stress conditions like ER stress, hypoxia and nutrient deprivation. Biologically, STC2 facilitates cells dealing with stress conditions and prevents apoptosis. Importantly, STC2 also promotes the development of acquired resistance to chemo- and radio- therapies. In addition, multiple groups have reported that STC2 overexpression promotes cell proliferation, migration and immune response. Therefore, the overexpression of STC2 is positively correlated with tumour growth, invasion, metastasis and patients' prognosis, highlighting its potential as a biomarker and a therapeutic target. This review focuses on discussing the regulation, biological functions and clinical importance of STC2 in human cancers. Future perspectives in this field will also be discussed.

miR-184 delays cell proliferation, migration and invasion in prostate cancer by directly suppressing DLX1

A number of previous studies have reported that dysregulated miR-184 expression is associated with the development of cancer. The aim of the present study was to investigate the role of miR-184 in prostate cancer (PC) and the mechanism underlying its effects. Data from human tumor tissue samples were collected from The CEancer Genome Atlas to determine the expression levels of miR-184 and DLX1. The miR-184 mimic and pcDNA3.1-DLX1 plasmid were utilized to induce overexpression of miR-184 and DLX1 in Du145 cells, respectively. Cell Counting Kit-8, wound healing and Transwell assays were performed to examine the effects of miR-184 on the aggressiveness of PC cells. Dual-luciferase reporter gene assay was used to investigate the association between miR-184 and DLX1, and reverse transcription-quantitative PCR and western blot analyses were utilized to determine the mRNA and protein levels. miR-184 expression was found to be downregulated whereas DLX1 was upregulated in PC tissues compared with normal prostate tissues. Cell propagation, migration and invasion were all inhibited by miR-184 upregulation in Du145 cells. Dual luciferase reporter assay confirmed the association between miR-184 and DLX1. The inhibitory effect of miR-184 mimic on cell behaviors was reversed by upregulation of DLX1. These findings suggest that miR-184 plays a beneficial role in suppressing the tumorigenesis of PC by directly targeting DLX1, and it may represent a potential therapeutic strategy for PC.

Tripterine and miR-184 show synergy to suppress breast cancer progression

BACKGROUND

The anti-cancer activities of tripterine in human cells offer promising therapeutic solutions to patients living with cancer. However, the effects of tripterine on breast cancer (BC) have not been closely examined. This study was to investigate the underlying biological pathway through which tripterine and miR-184 influence BC progression.

METHODS

Two human BC cell lines (MCF-7 and BT-474) were cultured in this study. Different concentrations of tripterine (0, 5, 10 and 15 μM) were dissolved in dimethyl sulfoxide (DMSO) and then added to the cells. The expression of miR-184 was measured using qRT-PCR. The inhibitory impact of tripterine and miR-184 on BC development was assessed by CCK-8, BrdU, transwell, and wound healing assays. Western blot assay was also performed to analyze Bax and Bcl-2 protein expression of BC cells.

RESULTS

Findings indicated that tripterine suppressed BC cells' viability, proliferation, migration, invasion capacity and Bcl-2 protein expression, but it induced BC cells' Bax protein expression. It was also found miR-184 expression was high in the BC cell lines treated with tripterine and that miR-184 overexpression reduced the viability, proliferation, and invasion abilities of BC cells under tripterine treatment. Interference with miR-184 neutralized the effects of tripterine on BC cell viability, proliferation and invasion.

CONCLUSION

This research suggested that by interacting with miR-184, tripterine could restrain the progression of BC. This knowledge could be instrumental in developing highly effective treatment solutions for BC.

Model establishment of prognostic-related immune genes in laryngeal squamous cell carcinoma

BACKGROUND

Laryngeal squamous cell carcinoma (LSCC) is one of the most common malignant tumors of the head and neck in the world. At present, the treatment methods include surgery, radiotherapy, and chemotherapy, but the 5-year survival rate is still not ideal and the quality of life of the patients is low. Due to the relative lack of immunotherapy methods, this study aims to build a risk prediction model of related immune genes, which can be used to effectively predict the prognosis of laryngeal cancer patients, and provide targets for subsequent immunotherapy.

METHODS

We collected the 111 cases of laryngeal squamous cell carcinoma and 12 matched normal samples in the The Cancer Genome Atlas Database (TCGA) gene expression quantification database. The differentially expressed related immune genes were screened by R software version 3.5.2. The COX regression model of immune related genes was constructed, and the sensitivity and specificity of the model were evaluated. The risk value was calculated according to the model, and the risk curve was drawn to verify the correlation between related immune genes, risk score, and clinical traits.

RESULTS

We selected 8 immune-related genes that can predict the prognosis of LSCC in a COX regression model and plotted the Kaplan-Meier survival curve. The 5-year survival rate of the high-risk group was 16.5% (95% CI: 0.059-0.459), and that of the low-risk group was 72.9% (95% CI: 0.555-0.956). The area under the receiver operating characteristic (ROC) curve was used to confirm the accuracy of the model (AUG = 0.887). After univariate and multivariate regression analysis, the risk score can be used as an independent risk factor for predicting prognosis. The risk score (P = .021) was positively correlated with the clinical Stage classification.

CONCLUSION

We screened out 8 immune genes related to prognosis: RBP1, TLR2, AQP9, BTC, EPO, STC2, ZAP70, and PLCG1 to construct risk value models, which can be used to speculate the prognosis of the disease and provide new targets for future immunotherapy.

miRNA signature in glioblastoma: Potential biomarkers and therapeutic targets

MicroRNAs (miRNAs) are transcripts with sizes of about 22 nucleotides, which are produced through a multistep process in the nucleus and cytoplasm. These transcripts modulate the expression of their target genes through binding with certain target regions, particularly 3' suntranslated regions. They are involved in the pathogenesis of several kinds of cancers, such as glioblastoma. Several miRNAs, including miR-10b, miR-21, miR-17-92-cluster, and miR-93, have been up-regulated in glioblastoma cell lines and clinical samples. On the other hand, expression of miR-7, miR-29b, miR-32, miR-34, miR-181 family members, and a number of other miRNAs have been decreased in this type of cancer. In the current review, we explain the role of miRNAs in the pathogenesis of glioblastoma through providing a summary of studies that reported dysregulation of these epigenetic effectors in this kind of brain cancer.

Effect of miR-184 on Proliferation and Apoptosis of Pancreatic Ductal Adenocarcinoma and Its Mechanism

Objective:

Previous studies have shown that abnormal expression of microRNA-184 leads to a variety of cancers, including pancreatic ductal adenocarcinoma, suggesting microRNA-184 as a new treatment target for pancreatic ductal adenocarcinoma. However, the molecular mechanism of microRNA-184 in pancreatic ductal adenocarcinoma remains unclear. It is important to investigate the effect and role of microRNA-184 in pancreatic ductal adenocarcinoma.

Methods:

The clinical and laboratory inspection data of 120 patients with pancreatic cancer admitted to the First Affiliated Hospital of Anhui Medical University were compared. MicroRNA-184 expression in tumor tissues and cells was evaluated using reverse transcription polymerase chain reaction. Flow cytometry and Annexin V/propidium iodide staining were performed to examine cell cycle and apoptosis. Western blotting analysis was conducted to measure the protein expression of p-PI3K, p-AKT, JNK1, C-Myc, C-Jun, caspase-9, and caspase-3.

Results:

MicroRNA-184 expression was low in patients with pancreatic ductal adenocarcinoma. Survival curve showed that patients with lower expression of microRNA-184 in tumor tissues had a worse prognosis and shorter survival time (P < .05), and the multivariate analysis identified that microRNA-184 was an independent prognostic indicator (P < .05). In vitro studies showed that microRNA-184 overexpression induced apoptosis and suppressed cell cycle transition from G1 to S and G2 phases in pancreatic ductal adenocarcinoma cells. Furthermore, molecular studies revealed that inhibition of microRNA-184 promoted the gene expression of p-PI3K, p-AKT, JNK1, C-Myc, and C-Jun compared with the control group. Overexpression of microRNA-184 led to significantly increased expression of caspase-9 and caspase-3 and significantly decreased expression of Bcl-2.

Conclusion:

This study suggests that microRNA-184 inhibits the proliferation and promotes the apoptosis of pancreatic ductal adenocarcinoma cells by downregulating the expression of C-Myc, C-Jun, and Bcl-2. Our verification of the role of microRNA-184 may provide a novel biomarker for the diagnosis, therapy, and prognosis of pancreatic ductal adenocarcinoma.

MicroRNA-184 negatively regulates corneal epithelial wound healing via targeting CDC25A, CARM1, and LASP1

Background

MicroRNAs (miRNAs) play critical roles in corneal development and functional homeostasis. Our previous study identified miR-184 as one of the most highly expressed miRNAs in the corneal epithelium. Even though its expression level plummeted dramatically during corneal epithelial wound healing (CEWH), its precise role in mediating corneal epithelial renewal was unresolved. The present study aimed to reveal the function and mechanism of miR-184 in regulating CEWH.

Methods

Quantitative RT-PCR analysis characterized the miR-184 expression pattern during CEWH in mice. Ectopic miR-184 injection determined its effect on this process in vivo. We evaluated the effects of miR-184 and its target genes on the proliferation, cell cycle, and migration of human corneal epithelial cells (HCECs) using MTS, flow cytometry, and wound-healing assay, respectively. Bioinformatic analysis, in conjunction with gene microarray analysis and cell-based luciferase assays, pinpointed gene targets of miR-184 contributing to CEWH.

Results

MiR-184 underwent marked downregulation during mouse CEWH. Ectopic miR-184 overexpression delayed this process in mice. Furthermore, miR-184 transfection into HCECs significantly inhibited cell proliferation, cell cycle progression, and cell migration. MiR-184 directly targeted CDC25A, CARM1, and LASP1, and downregulated their expression in HCECs. CARM1 downregulation inhibited both HCEC proliferation and migration, whereas a decrease in LASP1 gene expression only inhibited migration.

Conclusions

Our results demonstrate that miR-184 inhibits corneal epithelial cell proliferation and migration via targeting CDC25A, CARM1, and LASP1, suggesting it acts as a negative modulator during CEWH. Therefore, identifying strategies to suppress miR-184 expression levels has the potential to promote CEWH.

Stanniocalcin 2 contributes to aggressiveness and is a prognostic marker for oral squamous cell carcinoma

Stanniocalcin 2 (STC2), a glycoprotein that regulates calcium and phosphate homeostasis during mineral metabolism, appears to display multiple roles in tumorigenesis and cancer progression. This study aimed to access the prognostic value of STC2 in oral squamous cell carcinoma (OSCC) and its implications in oral tumorigenesis. STC2 expression was examined in 2 independent cohorts of OSCC tissues by immunohistochemistry. A loss-of-function strategy using shRNA targeting STC2 was employed to investigate STC2 in vitro effects on proliferation, apoptosis, migration, invasion, epithelial-mesenchymal transition (EMT) and possible activation of signaling pathways. Moreover, STC2 effects were assessed in vivo in a xenograft mouse cancer model. High expression of STC2 was significantly associated with poor disease-specific survival (HR: 2.67, 95% CI: 1.37-5.21, p = 0.001) and high rate of recurrence with a hazard ratio of 2.80 (95% CI: 1.07-5.71, p = 0.03). In vitro downregulation of STC2 expression in OSCC cells attenuated proliferation, migration and invasiveness while increased apoptotic rates. In addition, the STC2 downregulation controlled EMT phenotype of OSCC cells, with regulation on E-cadherin, vimentin, Snail1, Twist and Zeb2. The reactivation of STC2 was observed in the STC2 knockdown cells in the in vivo xenograft model, and no influence on tumor growth was observed. Modulation of STC2 expression levels did not alter consistently the phosphorylation status of CREB, ERK, JNK, p38, p70 S6K, STAT3, STAT5A/B and AKT. Our findings suggest that STC2 overexpression is an independent marker of OSCC outcome and may contribute to tumor progression via regulation of proliferation, survival and invasiveness of OSCC cells.

LncRNA SNHG8 accelerates proliferation and inhibits apoptosis in HPV-induced cervical cancer through recruiting EZH2 to epigenetically silence RECK expression

Infection of human papillomaviruses (HPVs), such as subtypes HPV16 and HPV18 is carcinogenic to human and is prominent cause of HPV-positive cervical carcinoma (CC). A closer investigation into the mechanism of HPV-induced CC may stimulate the generation of an improved therapy treating cervical cancer. Our study herein interrogated the function of a small nucleolar RNA host gene 8 (SNHG8) in HPV-induced CC. As a result, a notable increase of SNHG8 in HPV-induced CC cells was found compared with HPV-negative CC cells. Functionally, it identified that SNHG8 aggravated the cell proliferation and migration in Cell Counting Kit-8 and transwell assays. Besides, flow cytometry apoptosis assay displayed that blockade of SNHG8 exacerbated apoptosis of HPV-positive CC cells. As detected by fluorescence in situ hybridization analysis and subcellular fractionation assay, SNHG8 was primarily expressed in the nucleus and exerted suppressive role on reversion inducing cysteine-rich protein with kazal motifs (RECK) expression, which implied a potential transcriptional regulation of SNHG8 on RECK level. Mechanically, SNHG8 was disclosed to interact with enhancer of zeste homolog 2 (EZH2) based on RNA immunoprecipitation assay. ChIP assay further unveiled the occupancy of EZH2 in the promoter region of RECK. An additional chromatin immunoprecipitation assay highlighted that SNHG8 intensified the enrichment of EZH2 and H3K27me3 in RECK promoter region. Altogether, it reflected that SNHG8 recruited EZH2 to downregulate RECK expression, leading to HPV-induced CC aggravation.

Functional Analysis of the 3' Untranslated Region of the Human GRIN1 Gene in Regulating Gene Expression in vitro

PURPOSE

Abnormal expression of the NR1 subunit of the N-methyl-d-aspartate (NMDA) receptor may potentially increase the susceptibility to neuropsychiatric diseases. The purpose of this study was to investigate the functional sequence of the 3'UTR of the human GRIN1 gene, which encodes the GluN1 receptor to determine the effect on the expression of GluN1 receptor.

METHODS

We transferred seven recombinant pmirGLO recombinant vectors containing the 3'UTR truncated fragment of the GRIN1 gene into HEK-293, SK-N-SH, and U87 cell lines and compared the relative fluorescence intensity of adjacent length fragments. The TargetScan database was used to predict miRNAs. Then, miRNA mimics/inhibitors were co-transfected into the three cell lines with the 3'UTR of GRIN1 (pmirGLO - GRIN1), to investigate their influence on GRIN1 gene expression.

RESULTS

Compared with the pmirGLo-Basic vector, the relative fluorescence intensity of the complete GRIN1 gene 3'UTR recombinant sequence -27 bp - +1284 bp (the next base of the stop codon is +1) was significantly decreased in all three cell lines. The relative fluorescence intensities were significantly different between -27 bp - +294 bp and -27 bp - +497 bp regions, and between -27 bp - +708 bp and -27 bp - +907 bp regions. According to the prediction of the TargetScan database and analysis, miR-212-5p, miR-324-3p and miR-326 may bind to +295 bp - +497 bp, while miR-491-5p may bind to +798 bp - +907 bp. After co-transfection of miRNA mimic/inhibitor or mimic/inhibitor NC with a recombinant vector in the 3'UTR region of GRIN1 gene, we found that has-miR-491-5p inhibited GRIN1 expression significantly in all three cell lines, while has-miR-326 inhibitor upregulated GRIN1 expression in HEK-293 and U87 cells.

CONCLUSION

miR-491-5p may bind to the 3'UTR of the GRIN1 gene (+799 bp - +805 bp, the next base of the stop codon is +1) and down-regulate gene expression in HEK-293, SK-N-SH, and U87 cell lines, which implicates a potential role of miR-491-5p in central nervous system diseases.

A Novel Mechanism of BAM8-22 Inhibiting Microglia Activation: Represses CX3CR1 Expression via Upregulating miR-184

Bone cancer pain (BCP) is the most common type of pain in cancer patients, during which microglia cells were activated. A previous study showed BAM8-22 had the ability to alleviate BCP via inhibiting microglia activation while the mechanism was not clear. This study aims to investigate the specific mechanism of BAM8-22 inhibiting microglia activation. This study was mainly investigated in BCP mice or LPS-treated microglia BV-2 cells. The behavior tests of mice were performed at 0, 1, 2, 12, and 24 h after BAM8-22 treatment. The expression of miR-184 and CX3CR1 mRNAs was detected by quantitative RT-PCR. The expression of CX3CR1 protein and microglia activation marker, Iba-1, was measured by western blot analysis. The levels of TNF-α and IL-1β were detected by ELISA. Dual-luciferase assay was performed to verify the combination between miR-184 and CX3CR1. After BAM8-22 treatment, increased miR-184 level was observed in both BCP mice and LPS-treated BV-2 cells, with the downregulated expression of Iba-1 and inflammatory cytokines, namely the inhibition of microglia activation. The inhibition of miR-184 reversed the inhibitory effect of BAM8-22 on microglia activation. Further, in vitro studies showed that miR-184 bound to the 3'UTR of CX3CR1 and inhibited microglia activation via repressing CX3CR1 expression. What's more, the suppression of CX3CR1 expression eliminated the reversal effect of the miR-184 inhibitor on BAM8-22-induced microglia activation and decreased Iba-1 expression and pro-inflammatory cytokine secretion. In BCP models, miR-184 was upregulated by BAM8-22 and the elevated level of miR-184 bound to the 3'UTR region of CX3CR1 and repressed CX3CR1 expression, thus inhibiting the microglia activation, suggesting the potential application of miR-184/CX3CR1 for BCP treatment.

Long non-coding RNA HOTAIR/microRNA-206 sponge regulates STC2 and further influences cell biological functions in head and neck squamous cell carcinoma

Objective

It is essential to characterize underlying molecular mechanism associated with head and neck squamous cell carcinoma (HNSCC) and identify promising therapeutic targets. Herein, we explored role of homeobox transcript antisense RNA (HOTAIR) in HNSCC to regulate stanniocalcin‐2 (STC2) by sponging microRNA‐206 (miR‐206).

Methods

HNSCC‐related differentially expressed genes and regulation network amongst HOTAIR, miR‐206 and STC2 were identified. Next, effect of HOTAIR on cell biological functions of HNSCC was identified after transfection of cells with HOTAIR overexpressed plasmids or siRNA against HOTAIR. PI3K/AKT signalling pathway‐related gene expression was measured after miR‐206 and STC2 were suppressed. Cell invasion, migration and proliferation were assessed. Finally, tumour growth was assessed to determine the effects of HOTAIR/miR‐206/STC2 axis in vivo.

Results

HOTAIR specifically bound to miR‐206 and miR‐206 targeted STC2. Downregulated HOTAIR or upregulated miR‐206 suppressed HNSCC cell proliferation, invasion and migration. miR‐206 inhibited PI3K/AKT signalling pathway by down‐regulating STC2. Besides, silenced HOTAIR or overexpressed miR‐206 repressed the tumour growth of nude mice with HNSCC.

Conclusion

HOTAIR regulated HNSCC cell biological functions by binding to miR‐206 through STC2.