[MiR-218 Inhibits Migration and Invasion of Lung Cancer Cell by Regulating Robo1 Expression]

Non-coding RNAs and exosomal non-coding RNAs in lung cancer: insights into their functions

Lung cancer is the second most common form of cancer worldwide Research points to the pivotal role of non-coding RNAs (ncRNAs) in controlling and managing the pathology by controlling essential pathways. ncRNAs have all been identified as being either up- or downregulated among individuals suffering from lung cancer thus hinting that they may play a role in either promoting or suppressing the spread of the disease. Several ncRNAs could be effective non-invasive biomarkers to diagnose or even serve as effective treatment options for those with lung cancer, and several molecules have emerged as potential targets of interest. Given that ncRNAs are contained in exosomes and are implicated in the development and progression of the malady. Herein, we have summarized the role of ncRNAs in lung cancer. Moreover, we highlight the role of exosomal ncRNAs in lung cancer.

Circ_0068087 Silencing Ameliorates Oxidized Low-Density Lipoprotein-Induced Dysfunction in Vascular Endothelial Cells Depending on miR-186-5p-Mediated Regulation of Roundabout Guidance Receptor 1

Background: Circular RNAs (circRNAs) are endogenous non-coding RNAs involved in the progression of atherosclerosis (AS). We investigated the role of circ_0068087 in AS progression and its associated mechanism.

Methods: The 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay, flow cytometry, and enzyme-linked immunosorbent assay (ELISA) were performed to analyze the viability, apoptosis, and inflammatory response of HUVECs, respectively. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and the Western blot assay were performed to measure the expression of RNA and protein. Cell oxidative stress was analyzed using commercial kits. The dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were conducted to verify the interaction between microRNA-186-5p (miR-186-5p) and circ_0068087 or roundabout guidance receptor 1 (ROBO1).

Results: Oxidized low-density lipoprotein (ox-LDL) exposure upregulated the circ_0068087 level in HUVECs. ox-LDL-induced dysfunction in HUVECs was largely attenuated by the silence of circ_0068087. Circ_0068087 negatively regulated the miR-186-5p level by interacting with it in HUVECs. Circ_0068087 knockdown restrained ox-LDL-induced injury in HUVECs partly by upregulating miR-186-5p. ROBO1 was a downstream target of miR-186-5p in HUVECs. Circ_0068087 positively regulated ROBO1 expression by sponging miR-186-5p in HUVECs. MiR-186-5p overexpression exerted a protective role in ox-LDL-induced HUVECs partly by downregulating ROBO1.

Conclusion: Circ_0068087 interference alleviated ox-LDL-induced dysfunction in HUVECs partly by reducing ROBO1 expression via upregulating miR-186-5p.

MicroRNA-32 and MicroRNA-548a Promote the Drug Sensitivity of Non-Small Cell Lung Cancer Cells to Cisplatin by Targeting ROBO1 and Inhibiting the Activation of Wnt/β-Catenin Axis

Background

The roles of microRNA (miR)-32 and miR-548a in non-small cell lung cancer (NSCLC) have been studied. But their influences on NSCLC cells to cisplatin (DDP) resistance remain elusive. This study estimated the mechanisms of miR-32 and miR-548a in NSCLC cells to DDP.

Methods

Differentially expressed miRs in DDP-sensitive and resistant tissues were screened out using a GSE56036 chip. Then the predictive efficacies of miR-32 and miR-548a on DDP resistance were analyzed in NSCLC patients. The target mRNAs of miR-548a and miR-32 were predicted. miR-548a and miR-32 were knocked down to assess the influences of miR-32 and miR-548a on NSCLC growth. DDP-resistant cells were constructed and miR-32 and miR-548a expression was detected in resistant cells. After miR-32 and miR-548a knockdown, the IC50 value of DDP was detected. Then, the activation level of Wnt/β-catenin pathway was detected. The roles of miR-32 and miR-548a in NSCLC growth in vivo were detected by tumorigenesis experiment.

Results

miR-32 and miR-548a were poorly expressed in DDP-resistant NSCLC. miR-32 and miR-548a mimic enhanced the DDP sensitivity of NSCLC cells. Both miR-32 and miR-548a targeted ROBO1, and overexpression of ROBO1 inhibited the promotion of miR-32 and miR-548a mimic on DDP sensitivity. ROBO1 activated the Wnt/β-catenin pathway, thus enhancing the DDP resistance.

Conclusion

miR-32 and miR-548a target ROBO1 and inhibit Wnt/β-catenin activation, thus promoting the drug sensitivity of NSCLC cells to DDP.

MiR-218-5p Suppresses the Progression of Retinoblastoma Through Targeting NACC1 and Inhibiting the AKT/mTOR Signaling Pathway

Introduction

MicroRNA-218-5p (miR-218-5p) was involved in the progression of multiple tumors as a tumor suppressor miRNA. Its specific role on human retinoblastoma (RB) cells remains unknown.

Methods

We constructed the miR-218-5p overexpression and knockdown cells to detect their role on RB cell line WERI-Rb-1, and we analyzed its binding sites on TargetScan. CCK8 and clonogenic assays were performed to detect cell viability. Flow cytometry was used for the detection of cell apoptosis.

Results

Our results showed that the miR-218-5p inhibitor enhanced cell viability and blocked the apoptosis in RB cells. The AKT/mTOR signaling pathway was also inhibited by the miR-218-5p inhibitor. MiR-218-5p mimics lead to diametrically opposite results. Nucleus accumbens-associated 1 (NAC1) encoded by the NACC1 gene is involved in the regulation of many biological functions, including gene transcription, protein degradation of ubiquitin pathway, cell viability, and apoptosis. In this research, dataset analysis suggested that NACC1 might be a downstream target of miR-218-5p. Then, qPCR and Western blot analysis proved that miR-218-5p inhibited the expression of NACC1 in RB cells. NACC1 could promote cell viability and inhibit the apoptosis by activating the AKT/mTOR signaling pathway. MiR-218-5p mimics blocked the enhancement of cell growth induced by NACC1 overexpression as well as the activation of the AKT/mTOR signaling pathway in RB cells.

Discussion

MiR-218-5p inhibited cell growth by targeting NACC1 and suppressing the AKT/mTOR signaling pathway. MiR-218-5p/NACC1/AKT/mTOR might be a new target axis for the clinical treatment strategy.

Effects of miR-218-1-3p and miR-149 on proliferation and apoptosis of non-small cell lung cancer cells

The aim of the present study was to explore the effects of miR-218-1-3p and miR-149 on the biological function of non-small cell lung cancer (NSCLC) cells A549. Paired NSCLC and adjacent tissues were obtained from 50 NSCLC patients admitted to Shandong Provincial Chest Hospital Affiliated to Shandong University (Jinan, China) from April 2015 to May 2018. The expression levels of miR-218-1-3p and miR-149 were detected by reverse transcription-quantitative PCR (RT-qPCR). The lung adenocarcinoma A549 cells were assigned into the blank group (without transfection), negative control (NC) group (transfected with miRNA NC), and the transfected groups miR-218-1-3p mimic and miR-149 mimic groups. Proliferation and cell growth were determined by CCK-8 assay and cell invasion ability in vitro was assessed by Transwell assay. Flow cytometry was carried out for the detection of cell apoptosis. RT-qPCR results showed that the expression levels of miR-218-1-3p and miR-149 in NSCLC tissues were significantly lower than those in adjacent tissues (P<0.001). At 48 and 72 h, the cell growth of the A549 cells in the miR-218-1-3p mimic and miR-149 mimic groups was significantly lower than that in the NC and blank groups (P<0.05). The number of invasive cells in the miR-218-1-3p mimic and miR-149 mimic groups was significantly lower than that in the NC and blank groups (P<0.05). The apoptotic rate of A549 cells in the miR-218-1-3p mimic and miR-149 mimic groups was significantly higher than that in the NC and blank groups (P<0.05). In conclusion, upregulation of miR-218-1-3p and miR-149 can inhibit the proliferation, invasion and migration of A549 cells in NSCLC, thereby promoting the apoptosis of A549 cells. Thus, miR-218-1-3p and miR-149 can be used as new molecular targets for the diagnosis and treatment of NSCLC.

Survivin is a prognostic indicator in glioblastoma and may be a target of microRNA-218

Accumulating evidence has revealed that survivin expression is associated with a malignant phenotype and poor prognosis in glioma. Survivin is also a potential target of microRNA (miRNA/miR)-218. The aim of the present study was to investigate the expression and function of survivin in glioblastoma, and to examine the association between survivin and miR-218. For that purpose, survivin mRNA levels were analyzed in 144 frozen samples of glioblastoma using whole-genome RNA sequencing. In vitro cell proliferation, migration, invasion and apoptosis assays were performed, and survivin expression was detected by western blotting. The results revealed that the mRNA expression levels of survivin were negatively and significantly associated with overall survival in glioblastoma. Further in vitro analyses suggested that miR-218 may inhibit the expression of survivin. Expression of miR-218 in the LN229 cell line was significantly lower than that in the immortalized human gliocyte HEB cell line. miR-218 markedly inhibited tumor cell proliferation, migration and invasion capacities, and decreased apoptosis. miR-218 also inhibited the expression of survivin. These results indicated that survivin may be a target of miR-218 and could serve as a predictive biomarker.