MiR-492 exerts tumor-promoting function in prostate cancer through repressing SOCS2 expression

hsa_circ_0129047 Upregulates LYVE1 to Inhibit Hepatocellular Carcinoma Progression by Sponging miR-492

Compelling evidence indicates the regulatory role of circular RNAs in cancers, including hepatocellular carcinoma (HCC). Our study aimed to elucidate the regulatory function of circ_0129047 in HCC progression. A reverse transcription-quantitative polymeric chain reaction was conducted to detect the expression of circ_0129047, lymphatic vessel endothelial hyaluronan receptor-1 (LYVE1), and miR-492 in HCC tissues and cells. The characteristics of circ_0129047 were determined by evaluating the nuclear and cytoplasmic fractions and by RNase R digestion assays. The cell counting kit-8 assay, scratch wound, and transwell invasion assays were used to examine the effects of circ_0129047 overexpression, miR-492 mimic, and LYVE1 overexpression on the proliferation, migration, and invasion abilities of HCC cells in vitro. A mouse xenograft model was also established. The relationship between miR-492 and circ_0129047 or LYVE1 was clarified using luciferase reporter and Argonaute-2 RNA immunoprecipitation assays. We found that circ_0129047 and LYVE1 were poorly expressed in HCC tissues and cells, whereas miR-492 was upregulated. Overexpression of circ_0129047 inhibits HCC cell proliferation, migration, and invasion and delays in vivo tumor growth. Furthermore, circ_0129047 sponged miR-492, and 3'UTR LYVE1 was a direct target of miR-492. Additionally, LYVE1 overexpression reduced the oncogenic activity of the miR-492 mimic, whereas the miR-492 mimic abolished the antimigratory, antiproliferative, and anti-invasive effects of circ_0129047 overexpression in HCC cells. These data suggest that circ_0129047 exerts a tumor-suppressive role in HCC by sponging miR-492 away from LYVE1 and that the circ_0129047/miR-492/LYVE1 axis may be a promising target for HCC treatment.

Circulating miRNAs in Serum as Biomarkers for Early Diagnosis of Non-small Cell Lung Cancer

Background

Non-small cell lung cancer (NSCLC) accounts for about 85% of lung cancers. This study aimed to discover the potential miRNA biomarkers for early detection of NSCLC.

Methods

Total circulating miRNAs were extracted from six patients and six volunteers and run on the miRNA chip. The differentially expressed miRNAs acquired by data mining were intersected with chip results, and qRT-PCR were carried out. Then the differentially miRNAs were validated by using a validation cohort (120 participants). ROC curves were established to evaluate the diagnostic efficacy of the differentially circulating miRNAs. The target genes of the differential miRNAs were identified using the miRTarBase database, and follow-up GO and KEGG enrichment analysis were conducted.

Results

We identified 577 miRNA which screened according to the criteria (fold change > 2 and p value < 0.05). Among them, seven circulating miRNAs passed additional filtering based on data mining. These miRNAs were further validated in the training and validation cohort. miR-492, miR-590-3p, and miR-631 were differentially expressed in the patients’ serum, and the area under the ROC curve (AUC) values of these miRNAs were 0.789, 0.792, and 0.711, respectively. When using them as a combination to discriminate healthy volunteers from patients, the AUC reached 0.828 (95% CI, 0.750–0.905, p = 0.000) with a sensitivity of 86.7% and specificity of 71.7%. The follow-up enrichment analysis showed that target genes of three miRNA were associated with tumorigenesis and progression, such as cell cycle and P53 signaling pathway.

Conclusions

The combination of miR-492, miR-590-3p, and miR-631 can be utilized to distinguish healthy individuals and early-stage NSCLC patients.

Impact

The combination of miR-492, miR-590-3p, and miR-631 might be a promising serum biomarker in patients for the early diagnosis of NSCLC.

CircTET1 Inhibits Retinoblastoma Progression via Targeting miR-492 and miR-494-3p through Wnt/β-catenin Signaling Pathway

Purpose: Retinoblastoma (RB) is a frequent intraocular malignancy in children. Circular RNA (circRNA) plays an essential role in regulating the occurrence and development of tumors. This study aimed at investigating the function and molecular basis of hsa_circ_0093996 (circTET1) in RB.Methods: The expression of circTET1, miR-492 and miR-494-3p was examined using quantitative real-time polymerase chain reaction. Cell proliferation, cycle arrest, apoptosis, migration and invasion of RB cells were detected using Cell Counting Kit-8 (CCK-8), colony formation assay, flow cytometry, scratch assay and transwell analysis, respectively. The levels of matrix metalloproteinase (MMP) 2, MMP9 and Wnt/β-catenin pathway-related proteins were measured via western blot assay. The association between circTET1 and miR-492/miR-494-3p was validated via dual-luciferase reporter assay and RNA pull-down assay. Xenograft assay was employed to analyze tumor growth in vivo.Results: CircTET1 level was reduced, while miR-492 and miR-494-3p levels were increased in RB tissues and cells. Overexpression of circTET1 inhibited proliferation, migration and invasion, and promoted apoptosis and cell cycle arrest in Y79 and WERI-Rb1 cells. Moreover, circTET1 impeded RB cell progression by sponging miR-492/miR-494-3p. Also, up-regulation of circTET1 restrained Wnt/β-catenin pathway via regulating miR-492 and miR-494-3p. Furthermore, circTET1 suppressed tumor growth in xenograft models.Conclusion: CircTET1 inhibited RB progression by sponging miR-492/miR-494-3p and inactivating the Wnt/β-catenin pathway, which provided new insights for RB treatment.

Association between miR-492 rs2289030 G>C and susceptibility to Hirschsprung disease in southern Chinese children

OBJECTIVE

Hirschsprung disease (HSCR) originates from disruption of normal neural crest cell migration, differentiation, and proliferation during the fifth to eighth weeks of gestation. This results in the absence of intestinal ganglion cells in the distal intestinal tract. However, genetic variations affecting embryonic development of intestinal ganglion cells are unclear. Therefore, this study aimed to investigated the potential value of miR-492 rs2289030 G>C as a marker of susceptibility to HSCR.

METHODS

In this case-control study in southern Chinese children, we collected samples from 1473 controls and 1470 patients with HSCR. TaqMan genotyping of miR-492 rs2289030 G>C was performed by real-time fluorescent quantitative polymerase chain reaction.

RESULTS

Multivariate logistic regression analysis showed that there was no significant association between the presence of the miR-492 rs2289030 G>C polymorphism and susceptibility to HSCR by evaluating the values of pooled odds ratios and 95% confidence intervals. Similarly, among different HSCR subtypes, rs2289030 G>C was also not associated with HSCR in hierarchical analysis.

CONCLUSIONS

Our results suggest that the miR-492 rs2289030 G>C polymorphism is not associated with susceptibility to HSCR in southern Chinese children. These results need to be further confirmed by investigating a more diverse ethnic population of patients with HSCR.

LncRNA WDFY3-AS2 suppresses proliferation and invasion in oesophageal squamous cell carcinoma by regulating miR-2355-5p/SOCS2 axis

Long non‐coding RNAs (lncRNAs) widely participate in ESCC development and progression; however, the prognostic factors and therapeutic strategies implicated in ESCC development and progression remain to be under investigation. The purpose of the current study was to explore whether WDFY3‐AS2 may be a potential prognostic factor and investigate its biological functions in ESCC. Here, WDFY3‐AS2 was frequently down‐regulated in ESCC tissues and cells, and its expression was correlated with TNM stage, lymph node metastasis and poor prognosis of ESCC patients. Moreover, WDFY3‐AS2 down‐regulation significantly promoted cell proliferation and invasion, whereas WDFY3‐AS2 up‐regulation markedly suppressed cell proliferation and invasion in ESCC EC9706 and TE1 cells, coupled with EMT phenotype alterations. WDFY3‐AS2 functioned as a competing endogenous RNA (ceRNA) for sponging miR‐2355‐5p, further resulted in the up‐regulation of its target gene SOCS2, followed by suppression of JAK2/Stat5 signalling pathway, to suppress ESCC cell proliferation and invasion in EC9706 and TE1 cells. These findings suggest that WDFY3‐AS2 may participate in ESCC development and progression, and may be a novel prognostic factor for ESCC patients, and thus targeting WDFY3‐AS2/miR‐2355‐5p/SOCS2 signalling axis may be a novel therapeutic strategy for ESCC patients.

Analysis of Cells Proliferation and MicroRNAs Expression Profile in Human Chondrosarcoma SW1353 Cells Exposed to Iodine-125 Seeds Irradiation

Chondrosarcoma is the second most common bone malignancy in adults, and it is often resistant to traditional chemotherapy and radiation therapy. Permanent implantation of iodine-125 (¹²⁵I) seeds has been explored for the treatment of many types of cancer. In this study, the aim was to investigate the proliferative and microRNA (miRNA) effects of ¹²⁵I seeds irradiation on human chondrosarcoma SW1353 cells. First, a new in vitro ¹²⁵I seed irradiation model was established, and cell viability and miRNA microarray assays were performed before and after exposure to the ¹²⁵I seeds. Cell proliferation was inhibited, and miRNA expression was substantially altered by irradiation exposure. The inhibition of cell proliferation was positively correlated with increased radiation doses, with cells showing the highest total radiation dose 7 days after irradiation. A total of 2549 miRNAs were detected in the SW1353 cells after exposure to 6 Gy of radiation, which included 189 differentially expressed miRNAs (98 upregulated and 91 downregulated). Four miRNAs were found to play important roles in the inhibition of cell proliferation after irradiation exposure, including miR-1224-5p, miR-492, miR-135b-5p, and miR-6839-5p. The target genes of the associated miRNAs mentioned were vascular endothelial growth factor A (VEGFA), C-X-C motif chemokine 12 (CXCL12), mitogen-activated protein kinase kinase kinase kinase 3 (MAP4K3), and apoptosis facilitator Bcl-2-like protein 14 (BCL2L14). Hence, the mitogen-activated protein kinase signaling pathway may be involved in how chondrosarcoma cells respond to ¹²⁵I seed irradiation.

miR-492 Promotes Cancer Progression by Targeting GJB4 and Is a Novel Biomarker for Bladder Cancer

Background

Bladder cancer is the most common urinary system malignancy in the United States and is characterized by its diverse prognosis and high recurrence rate. However, the molecular mechanisms underlying its progression remain unknown. Accumulating evidence suggests a critical role for miRNAs in bladder cancer progression.

Methods and results

In this study, we found that miR-492 expression levels were significantly higher in bladder cancer tissue and the serum of bladder cancer patients by bioinformatics analysis and a panel of clinical samples. The results of receiver operating characteristic curve analysis suggested the potential diagnostic value of serum miR-492 for bladder cancer. In vitro and in vivo functional assays showed that knockdown of miR-492 suppressed proliferation and metastasis of bladder cancer cells. Gap junction beta-4 protein was predicted to be a direct target of miR-492, which was validated using a luciferase reporter assay. Further cellular functional assays showed that suppression of miR-492 abrogated bladder cancer cell proliferation and metastasis by targeting gap junction beta-4 protein.

Conclusion

miR-492 promotes cancer progression by targeting GJB4 and is a novel biomarker for bladder cancer.

Functions of N6-methyladenosine and its role in cancer

N6-methyladenosine (m6A) is methylation that occurs in the N6-position of adenosine, which is the most prevalent internal modification on eukaryotic mRNA. Accumulating evidence suggests that m6A modulates gene expression, thereby regulating cellular processes ranging from cell self-renewal, differentiation, invasion and apoptosis. M6A is installed by m6A methyltransferases, removed by m6A demethylases and recognized by reader proteins, which regulate of RNA metabolism including translation, splicing, export, degradation and microRNA processing. Alteration of m6A levels participates in cancer pathogenesis and development via regulating expression of tumor-related genes like BRD4, MYC, SOCS2 and EGFR. In this review, we elaborate on recent advances in research of m6A enzymes. We also highlight the underlying mechanism of m6A in cancer pathogenesis and progression. Finally, we review corresponding potential targets in cancer therapy.

LncRNA HIF1A-AS1 contributes to ventricular remodeling after myocardial ischemia/reperfusion injury by adsorption of microRNA-204 to regulating SOCS2 expression

Objectives: Long non-coding RNAs (lncRNAs) serve pivotal roles in heart disease, while the role of lncRNA hypoxia-inducible factor 1α-antisense RNA 1 (HIF1A-AS1) is rarely mentioned. Therefore, the objective of this study was to investigate the mechanism of lncRNA HIF1A-AS1 regulating suppressor of cytokine signaling 2 (SOCS2) expression by adsorption of microRNA-204 (miR-204) on ventricular remodeling after myocardial ischemia-reperfusion (I/R) injury in mice. Methods: The mouse model of I/R was established by left coronary artery occlusion. The expression of HIF1A-AS1, miR-204 and SOCS2 was determined. The mice were injected with HIF1A-AS1-siRNA, miR-204 mimics or their controls to investigate their effects on cardiac function and ventricular remodeling of mice after I/R injury. The binding relationship between HIF1A-AS1 and miR-204 as well as between miR-204 and SOCS2 were verified. Results: HIF1A-AS1 and SOCS2 were upregulated and miR-204 was downregulated in myocardial tissues in mice after I/R injury. LVEDD, LVEDS, LVEDP, LVMI and RVMI expression reduced while LVEF, LVFS, +dp/dt max and - dp/dt max increased through knockdown HIF1A-AS1 and upregulated miR-204. The expression of BNP, cTnI, LDH, CK, TNF-α, IL-1β, IL-6 and β-MHC reduced, and the expression of α-MHC increased when HIF1A-AS1 was poorly expressed and miR-204 was highly expressed. Silencing HIF1A-AS1 and upregulating miR-204 inhibited apoptosis of cells. LncRNA HIF1A-AS1 could act as ceRNA to adsorb miR-204 to suppress miR-204 expression and elevate SOCS2 expression. Conclusion: Our study provides evidence that downregulation of HIF1A-AS1 and upregulation of miR-204 could alleviate ventricular remodeling and improve cardiac function in mice after myocardial I/R injury via regulating SOCS2.