MicroRNA-490-5p is a novel tumor suppressor targeting c-FOS in human bladder cancer

Epigenetic regulatory protein chromobox family regulates multiple signalling pathways and mechanisms in cancer

Signal transduction plays a pivotal role in modulating a myriad of critical processes, including the tumour microenvironment (TME), cell cycle arrest, proliferation and apoptosis of tumour cells, as well as their migration, invasion, and the epithelial-mesenchymal transition (EMT). Epigenetic mechanisms are instrumental in the genesis and progression of tumours. The Chromobox (CBX) family proteins, which serve as significant epigenetic regulators, exhibit tumour-specific expression patterns and biological functionalities. These proteins are influenced by a multitude of factors and could modulate the activation of diverse signalling pathways within tumour cells through alterations in epigenetic modifications, thereby acting as either oncogenic agents or tumour suppressors. This review aims to succinctly delineate the composition, structure, function, and expression of CBXs within tumour cells, with an emphasis on synthesizing and deliberating the CBXs-mediated activation of intracellular signalling pathways and the intricate mechanisms governing tumourigenesis and progression. Moreover, a plethora of contemporary studies have substantiated that CBXs might represent a promising target for the diagnosis and therapeutic intervention of tumour patients. We have also compiled and scrutinized the current research landscape concerning inhibitors targeting CBXs, aspiring to aid researchers in gaining a deeper comprehension of the biological roles and mechanisms of CBXs in the malignant evolution of tumours, and to furnish novel perspectives for the innovation of targeted tumour therapeutics.

Circ_0001361/miR-490-5p/IGF2 Axis Regulates the Viability and Apoptosis of Neuroblastoma Cells

BACKGROUND

Circular RNAs (circRNAs) are involved in the neuroblastoma (NB) development. Objectie: The study aimed to determine the biological behaviors of circ_0001361 and explore its underlying mechanism in NB.

METHODS

The circ_0001361, miR-490-5p, and IGF2 levels were measured using quantitative real-time polymerase chain reaction. Cellular processes were analyzed using MTT assay or fluorescence-activated cell sorting (FACS). Phosphorylated (p)-PI3K, p-AKT, Bax, and caspase-3 were tested by western blot. Dual-luciferase reporter analysis together with RNA pull-down analysis were utilized to evaluate the correlation of miR-490-5p and circ_0001361 or IGF2.

RESULTS

The results in this study illustrated that an elevation of circ_0001361 levels was observed in NB. Depletion of circ_0001361 suppressed the viability but facilitated apoptosis of NB cells. Circ_0001361 sponged miR-490-5p, which targeted to regulate IGF2. Inhibition of miR-490-5p rescued the effect induced by circ_0001361 knockdown, while deletion of IGF2 rescued the effect induced by the miR-490-5p inhibitor.

CONCLUSIONS

In summary, a loss of circ_0001361 inhibited NB progression via targeting the miR-490-5p/IGF2 axis, suggesting that circ_0001361 may be a novel therapeutical target of NB.

Connection between MiR-490 and CCND1 and GSK3β genes play an effective role in Wnt signaling pathway in colorectal cancer

The Wnt signaling pathway is identified as one of the main disrupted pathways in Colorectal cancer (CRC). Results from studies focusing on this route will aid greatly in the detection and treatment of CRC. MicroRNAs (MiRs), particularly MiR-490, has emerged as key regulator of gene expression in biological pathways, making it an attractive research target. This is notably true for the Wnt signaling pathway, which is usually disordered in CRC tissues. This study aimed to evaluate the expression level of MiR-490 isomiRs and determine some of its key target genes involved in Wnt signaling pathway in CRC tissues and cell lines, based on experimental and bioinformatics analysis. Elevated expression of GSK3β and CCND1 indicate that the progression of CRC tumor is associated with the inhibitory effect of MiR-490 isomiRs on the Wnt/β-catenin signaling pathway. This finding was supported by the observation of a positive connection between the expression pattern of miR-490-3p and 5p, and CCND1 and GSK3β in CRC. The valuable results of this study provide a means of identifying biomarkers with the potential to either inhibit or activate CRC cellular pathways.

The Role of miRNAs, circRNAs and Their Interactions in Development and Progression of Hepatocellular Carcinoma: An Insilico Approach

Hepatocellular carcinoma (HCC) is a type of malignant tumor. miRNAs are noncoding RNAs and their differential expression patterns are observed in HCC-induced by alcoholism, HBV and HCV infections. By acting as a competing endogenous RNA (ceRNA), circRNA regulates the miRNA function, indirectly controlling the gene expression and leading to HCC progression. In the present study, data mining was performed to screen out all miRNAs and circRNA involved in alcohol, HBV or HCV-induced HCC with statistically significant (≤0.05%) expression levels reported in various studies. Further, the interaction of miRNAs and circRNA was also investigated to explore their role in HCC due to various causative agents. Together, these study data provide a deeper understanding of the circRNA-miRNA regulatory mechanisms in HCC. These screened circRNA, miRNA and their interactions can be used as prognostic biomarkers or therapeutic targets for the treatment of HCC.

Evaluation of molecular signatures in the urinary bladder and upper tract urothelial carcinomas: a prospective controlled clinical study

Background

Urothelial carcinomas (UC) can be either in the upper or in the lower urinary tract or both. Urothelial bladder cancer (UBC) is more common than upper tract urothelial carcinoma (UTUC). This research was designed to study the difference between UBC and UTUC using the molecular pathways including (MAPK/ERK) pathway, cell cycle regulating genes, and oncogenic genes.

Methods

To study the discrepancy between UBC and UTUC, a prospective trial was carried out for 31 radical cystectomy and 19 nephrouretrectomy fresh-frozen specimens of UBC and UTUC patients, respectively. The expression level of mRNA of eight genes namely EGFR, ELK1, c-fos, survivin, TP53, RB1, FGFR3, and hTERT was assessed in normal adjacent tissues, UTUC, and UBC by RT-PCR.

Results

Comparison between UTUC and UBC regarding the expression level of mRNA of the EGFR, ELK1, c-fos, survivin, TP53, and FGFR3 had significant difference (p-value < 0.001), while the expression level of RB1 and hTERT level had no significance. Sensitivity/specificity of EGFR, Elk1, c-fos, survivin, TP53, and FGFR3 was 0.78/0.90, 0.84/0.90, 0.84/0.80, 0.84/0.96, 0.94/0.93, and 0.89/0.93, respectively, to differentiate between UTUC and UBC.

Conclusions

Despite the fact that UTUC and UBC share the same origin, there is a clear evidence that there is a molecular difference between them. This molecular difference could be the reason that UTUC is more aggressive than UBC.

LINC00958 promotes bladder cancer carcinogenesis by targeting miR-490-3p and AURKA

Background

Bladder cancer is a prevalent malignancy of the urinary system, in which long non-coding RNAs (lncRNAs) are highly associated. We aimed to elucidate the role of LINC00958 in bladder cancer.

Methods

LINC00958 expression levels were measured using qRT-PCR. The interaction of LINC00958-miR-490-3p-AURKA was analyzed by luciferase, RIP, and RNA pull-down assays. The biological roles of LINC00958, miR-490-3p, and AURKA in bladder cancer cells were analyzed using CCK8, BrdU, and transwell assays.

Results

Increased expression of LINC00958 and AURKA was observed in bladder cancer tissues and cell lines. Decreased LINC00958 expression repressed bladder cancer progression and downregulation of miR-490-3p accelerated bladder cancer cell progression. Moreover, LINC00958 sponges miR-490-3p to upregulate AURKA expression, thereby promoting carcinogenesis in bladder cancer cells.

Conclusions

Our study revealed that LINC00958 facilitated cell proliferation and invasion, and suppressed cell apoptosis by sponging miR-490-3p and upregulating AURKA, thus inspiring a new treatment method for bladder cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08882-6.

MicroRNA-490-3p and -490-5p in carcinogenesis: Separate or the same goal?

MicroRNA (miR)-490-3p and miR-490-5p, located on chromosome 7q33, are two independent mature products of miR-490 exerting distinct effects on tumor progression. miR-490-3p and miR-490-5p possess antitumor properties. miR-490-3p dysfunction has been associated with malignancies including colorectal cancer, while the abnormal function of miR-490-5p has been more considerably associated with bladder cancer (for example). At present, there are 30 and 11 target genes of miR-490-3p and miR-490-5p, respectively, that have been experimentally verified, of which the cyclin D1 (CCND1) gene is a common target. Through these target genes, miR-490-3p and miR-490-5p are involved in 7 and 3 signaling pathways, respectively, of which only 2 are shared regulatory signaling pathways. The present review introduces two competing endogenous RNA (ceRNA) regulatory networks centered on miR-490-3p and miR-490-5p. These networks may be important promoters of tumor cell proliferation, invasiveness, metastatic potential and apoptosis. Unlike miR-490-5p, miR-490-3p plays a unique role in promoting cancer. However, both are promising molecular markers for early cancer diagnosis and prognosis. In addition, miR-490-3p was also found to be associated with the chemical resistance of cisplatin and paclitaxel. The present review focuses on the abnormal expression of miR-490-3p and miR-490-5p in different tumor types, and their complex ceRNA regulatory networks. The clinical value of miR-490-3p and miR-490-5p in cancer diagnosis, prognosis and treatment is also clarified, and an explanation for the opposing effects of miR-490-3p in tumor research is provided.

KPNA2 interaction with CBX8 contributes to the development and progression of bladder cancer by mediating the PRDM1/c-FOS pathway

BACKGROUND

Bladder cancer (BCa) is a common malignancy characterized by high heterogeneity, yet the current treatment modalities are limited. The aim of the present investigation was to unravel the functional role of Karyopherin alpha 2 (KPNA2), a tumor facilitator identified in multiple malignancies, in the progression of BCa.

METHODS

BCa tissues and adjacent normal tissues were surgically resected and analyzed from patients with BCa to determine the expression profile of KPNA2 and Chromobox 8 (CBX8) by RT-qPCR, Western blot analysis and immunohistochemistry. The relationship among KPNA2, CBX8 and PR domain zinc finger protein 1 (PRDM1) was explored by co-immunoprecipitation and chromatin-immunoprecipitation. The functions of KPNA2, CBX8 and PRDM1 on BCa cell proliferation, migration and invasion were evaluated. Next, a nude mouse model of BCa was established for validating the roles of KPNA2, CBX8 and PRDM1 in vivo.

RESULTS

KPNA2 and CBX8 were highly expressed in BCa and are in association with dismal oncologic outcomes of patients with BCa. KPNA2 promoted nuclear import of CBX8. CBX8 downregulated PRDM1 by recruiting BCOR in the promoter region of PRDM1. Overexpression of KPNA2 promoted the malignant behaviors of BCa cells, which was counteracted by silencing of CBX8. Overexpressing PRDM1 attenuated the progression of BCa by inhibiting c-FOS expression. The tumor-promoting effects of KPNA2 via the PRDM1/c-FOS pathway were also validated in vivo.

CONCLUSION

Collectively, our findings attached great importance to the interplay between KPNA2 and CBX8 in BCa in mediating the development and progression of BCa, thus offering a promising candidate target for better BCa patient management.

miRNA‑490‑3p promotes the metastatic progression of invasive ductal carcinoma

MicroRNA (miRNA/mir)‑490‑3p has been defined as a tumor suppressor in different types of cancer, including breast cancer. However, miR‑490‑3p has been shown to function as a tumor suppressor and promoter in a context‑dependent manner in hepatocellular and lung cancer. Contrary to previous studies, the present study revealed that miR‑490‑3p expression was significantly higher in invasive ductal carcinoma (IDC) tissue specimens, the most common form of breast cancer, compared to tumor‑adjacent normal tissue specimens (n=20). Its expression was also higher in the more metastatic breast cancer cell line, MDA‑MB‑231, compared to the non‑metastatic breast cancer cell line, MCF7, and the moderately metastatic breast cancer cell line, MDA‑MB‑468. The expression of miR‑490‑3p was induced following transforming growth factor (TGF)‑β‑induced epithelial‑to‑mesenchymal transition (EMT) in MCF10A cells. Gain‑and loss‑of‑function assays revealed that the expression of miR‑490‑3p regulated the proliferation, colony formation, EMT, migration and invasion in vitro, but not the apoptosis of MDA‑MB‑468 and MDA‑MB‑231 cells. The knockdown of miR‑490‑3p expression in MDA‑MB‑231 cells inhibited experimental metastasis in a tumor xenograft assay. As in lung cancer, miR‑490‑3p was found to target and downregulate the expression of the tumor suppressor RNA binding protein poly r(C) binding protein 1 (PCBP1). PCBP1 protein and miR‑490‑3p expression inversely correlated in patients with ductal carcinoma in situ (DCIS; n=10; no nodal involvement) and IDC (n=10; different stages of metastatic progression) with a significantly higher miR‑490‑3p expression in patients with IDC compared to those with DCIS. The expression of miR‑490‑3p was negatively associated with both overall and disease‑free survival in the patients with breast cancer included in the present study. On the whole, the results confirm a pro‑metastatic role of miR‑490‑3p in IDC, establishing it as a biomarker for disease progression in these patients.

Deciphering of Key Pharmacological Pathways of Poria Cocos Intervention in Breast Cancer Based on Integrated Pharmacological Method

OBJECTIVE

Poria cocos (Fuling), a natural plant, has recently emerged as a promising strategy for cancer treatment. However, the molecular mechanisms of Poria cocos action in breast cancer remain poorly understood.

METHODS

TCMSP database was used to screen the potential active ingredients in Poria cocos. GEO database was used to identify differentially expressed genes. Network pharmacology was used to identify the specific pathways and key target proteins related to breast cancer. Finally, molecular docking was used to validate the results.

RESULTS

In our study, 237 targets were predicted for 15 potential active ingredients found in Poria cocos. An interaction network of predicted targets and genes differentially regulated in breast cancers was constructed. Based on the constructed network and further analysis including network topology, KEGG, survival analysis, and gene set enrichment analysis, 3 primary nodes were identified as key potential targets that were significantly enriched in the PPAR signaling pathway.

CONCLUSION

The results showed that potential active ingredients of Poria cocos might interfere with breast cancer through synergistic regulation of PTGS2, ESR1, and FOS.

miR-490: A potential biomarker and therapeutic target in cancer and other diseases

MicroRNAs (miRNAs) are small non-coding RNAs that function as posttranscriptional gene regulators. Among a pool of >2600 known human mature miRNAs, only a small subset have been functionally interrogated and a further smaller pool shown to be associated with the pathogenesis of a variety of diseases suggesting their critical role in maintaining homeostasis. Here, we draw your attention to one such miRNA, miR-490, that has been reported to be deregulated in a myriad of diseases (23 diseases) ranging from cardiomyopathy, depression, and developmental disorders to many cancer types (28 cancer types), such as hepatocellular carcinoma, gastric cancer, cancers of the reproductive and central nervous system among others. The prognostic and diagnostic potential of miR-490 has been reported in many diseases including cancer underlining its clinical relevance. We also collate a complex plethora of epigenetic (histone and DNA methylation), transcriptional (TF), and posttranscriptional (lncRNA and circRNA) mechanisms that have been shown to tightly regulate miR-490 levels. The targets of miR-490 involve a range of cancer-related genes involved in the regulation of various cancer hallmarks like cell proliferation, migration, and invasion, apoptotic cell death, angiogenesis, and so forth. Overall, our in-depth review highlights for the first time the emerging role of miR-490 in disease pathology, diagnosis, and prognosis that assigns a unique therapeutic potential to miR-490 in the era of precision medicine.

Circular RNA circ_0091579 Promotes Hepatocellular Carcinoma Proliferation, Migration, Invasion, and Glycolysis Through miR-490-5p/CASC3 Axis

Background: Hepatocellular carcinoma (HCC) is one of the most common malignancies with high invasion and metastasis capacities. Circular RNAs (circRNAs) were evidenced to take part in the progression of multifarious cancers, including HCC. However, the role of circ_0091579 in HCC progression has not been fully described. This study aimed to explore the function of circ_0091579 and its potential regulatory mechanism in the progression of HCC. Materials and Methods: The expression of circ_0091579, microRNA-490-5p (miR-490-5p), and cancer susceptibility candidate 3 (CASC3) in HCC tissues and cells was detected by quantitative real-time polymerase chain reaction. The circular characteristic and stability of circ_0091579 were verified by RNase R digestion and actinomycin D reaction assays. Cell proliferation, migration, and invasion were determined by methyl thiazolyl tetrazolium assay and Transwell assay, respectively. The level of glycolysis was evaluated by glucose consumption and lactate production. The levels of proteins were examined by Western blot. The interaction between miR-490-5p and circ_0091579 or CASC3 was certified by Dual-luciferase reporter assay. Results: circ_0091579 and CASC3 were upregulated, while miR-490-5p was downregulated in HCC tissues and cells. Silencing of either circ_0091579 or CASC3 suppressed cell proliferation, migration, invasion, and glycolysis in HCC cells. Moreover, miR-490-5p was verified to directly bind to circ_0091579 and CASC3. Circ_0091579 upregulated CASC3 by sponging miR-490-5p in HCC cells to promote cell proliferation, invasion, and migration. Conclusion: circ_0091579 promoted cell proliferation, migration, invasion, and glycolysis partially through miR-490-5p/CASC3 axis in HCC cells.

Bottom-Up Fabrication of Plasmonic Nanoantenna-Based High-throughput Multiplexing Biosensors for Ultrasensitive Detection of microRNAs Directly from Cancer Patients' Plasma

There is an unmet need in clinical point-of-care (POC) cancer diagnostics for early state disease detection, which would greatly increase patient survival rates. Currently available analytical techniques for early stage cancer diagnosis do not meet the requirements for POC of a clinical setting. They are unable to provide the high demand of multiplexing, high-throughput, and ultrasensitive detection of biomarkers directly from low volume patient samples ("liquid biopsy"). To overcome these current technological bottle-necks, herein we present, for the first time, a bottom-up fabrication strategy to develop plasmonic nanoantenna-based sensors that utilize the unique localized surface plasmon resonance (LSPR) properties of chemically synthesized gold nanostructures, gold triangular nanoprisms (Au TNPs), gold nanorods (Au NRs), and gold spherical nanoparticles (Au SNPs). Our Au TNPs, NRs, and SNPs display refractive index unit (RIU) sensitivities of 318, 225, and 135 nm/RIU respectively. Based on the RIU results, we developed plasmonic nanoantenna-based multiplexing and high-throughput biosensors for the ultrasensitive assay of microRNAs. MicroRNAs are directly linked with cancer development, progression, and metastasis, thus they hold promise as next generation biomarkers for cancer diagnosis and prognosis. The developed biosensors are capable of assaying five different types of microRNAs at an attomolar detection limit. These sets of microRNAs include both oncogenic and tumor suppressor microRNAs. To demonstrate the efficiency as a POC cancer diagnostic tool, we analyzed the plasma of 20-bladder cancer patients without any sample processing steps. Importantly, our liquid biopsy-based biosensing approach is capable of differentiating healthy from early ("non-metastatic") and late ("metastatic") stage cancer with a p value <0.0001. Further, receiver operating characteristic analysis shows that our biosensing approach is highly specific, with an area under the curve of 1.0. Additionally, our plasmonic nanoantenna-based biosensors are regenerative, allowing multiple measurements using the same biosensors, which is essential in low- and middle-income countries. Taken together, our multiplexing and high-throughput biosensors have the unmatched potential to advance POC diagnostics and meet global needs for early stage detection of cancer and other diseases (e.g., infectious, autoimmune, and neurogenerative diseases).

How microRNAs affect the PD-L1 and its synthetic pathway in cancer

Programmed cell death-ligand 1 (PD-L1) is a glycoprotein that is expressed on the cell surface of both hematopoietic and nonhematopoietic cells. PD-L1 play a role in the immune tolerance and protect self-tissues from immune system attack. Dysfunction of this molecule has been highlighted in the pathogenesis of tumors, autoimmunity, and infectious disorders. MicroRNAs (miRNAs) are endogenous molecules that are classified as small non-coding RNA with approximately 20-22 nucleotides (nt) length. The function of miRNAs is based on complementary interactions with target mRNA via matching completely or incompletely. The result of this function is decay of the target mRNA or preventing mRNA translation. In the past decades, several miRNAs have been discovered which play an important role in the regulation of PD-L1 in various malignancies. In this review, we discuss the effect of miRNAs on PD-L1 expression and consider the effect of miRNAs on the synthetic pathway of PD-L1, especially during cancers.

MicroRNA-4500 Inhibits Migration, Invasion, and Angiogenesis of Breast Cancer Cells via RRM2-Dependent MAPK Signaling Pathway

With the consideration of the dynamic role of microRNAs (miRNAs) in breast cancer, miRNAs may serve as therapeutic targets, helping to prevent development of therapy resistance, maintain stable disease, and prohibit metastatic spread. We identified the differentially expressed breast cancer-related gene ribonucleotide reductase subunit M2 (RRM2) as the study focus through microarray expression profiles. Next, the upstream regulatory microRNA (miR)-4500 of RRM2 was predicted using bioinformatics website analysis, and their binding was verified by a dual luciferase reporter gene assay. The regulatory effects of miR-4500 on breast cancer cell proliferation, apoptosis, migration, invasion, and capillary-like tube formation of endothelial cells were assessed by gain- and loss-of-function experiments. The experimental data revealed that miR-4500 was downregulated, whereas RRM2 was upregulated in breast cancer cells. Mechanistic analysis revealed that miR-4500 downregulated the RRM2 expression to inactivate the mitogen-activated protein kinase (MAPK) signaling pathway. Furthermore, miR-4500 exerted anti-tumor effects by targeting RRM2 through suppression of the MAPK signaling pathway in vitro, evidenced by attenuated cancer cell migration and invasion and capillary-like tube formation of endothelial cells. The in vivo experiments further corroborated in vitro results. Collectively, overexpressed miR-4500 could downregulate RRM2 and inhibit activation of the MAPK signaling pathway, thus attenuating breast cancer cell proliferation, invasion, migration, and angiogenesis and promoting breast cancer cell apoptosis.

Integrated analysis of miRNA and mRNA expression profiles in p53-edited PFF cells

p53 is the most frequently mutated gene in human cancers, with over half of all tumors harboring mutation at this locus. R248 and R249 (corresponding to porcine R241 and R242), are among the hotspot mutations frequently mutated in liver, lung, breast, and some other cancers. In this study, p53 gene was knocked out or point-edited (R241 and R242 were converted to 241W and 242S) in porcine fetal fibroblast (PFF) cells via CRISPR-Cas9 technique. High throughput sequencing of miRNA and mRNA uncovered a total of 225 differentially expressed miRNAs (DEMs) and 738 differentially expressed genes (DEGs) in the p53 knockout (p53-KO) cells, and a total of 211 DEMs and 722 DEGs in the point-modified (p53-241W242S) cells. Totally 28 annotated DEMs were found to overlap between p53-KO/p53-WT and p53-241W242S/p53-WT miRNAs datasets, of which miR-34 c, miR-218, miR-205, miR-105-1, miR-105-2, miR-206, miR-224 and miR-429 play important roles in p53 regulatory network. Among the top 10 DEGs in p53-KO and p53-241W242S cells, most genes were reported to be involved in tumors, cell proliferation or cell migration. p53-KO and p53-241W242S cells showed a significantly higher (P < 0.01) proliferation rate compared with p53-WT cells. In conclusion, genetic modifications of p53 gene significantly affect the expression levels of a large number of genes and miRNAs in the PFF cells. The p53-edited PFF cells could be used as non-tumor cell models for investigating the p53 signaling network, and as donor cells for somatic nuclear transfer, with the aim to develop porcine models with the corresponding p53 mutations.Abbreviations: CRISPR-Cas9: Clustered regularly interspaced short palindromic repeats-associated protein 9; PFF: porcine fetal fibroblasts; SCNT: somatic cell nuclear transfer; RNA sequencing: small RNA sequencing and mRNA sequencing; DEGs: differentially expressed mRNAs; DEMs: differentially expressed miRNAs.

Identification of FOS as a Candidate Risk Gene for Liver Cancer by Integrated Bioinformatic Analysis

Liver cancer is a lethal disease that is associated with poor prognosis. In order to identify the functionally important genes associated with liver cancer that may reveal novel therapeutic avenues, we performed integrated analysis to profile miRNA and mRNA expression levels for liver tumors compared to normal samples in The Cancer Genome Atlas (TCGA) database. We identified 405 differentially expressed genes and 233 differentially expressed miRNAs in tumor samples compared with controls. In addition, we also performed the pathway analysis and found that mitogen-activated protein kinases (MAPKs) and G-protein coupled receptor (GPCR) pathway were two of the top significant pathway nodes dysregulated in liver cancer. Furthermore, by examining these signaling networks, we discovered that FOS (Fos proto-oncogene, AP-1 transcription factor subunit), LAMC2 (laminin subunit gamma 2), and CALML3 (calmodulin like 3) were the most significant gene nodes with high degrees involved in liver cancer. The expression and disease prediction accuracy of FOS, LAMC2, CALML3, and their interacting miRNAs were further performed using a HCC cohort. Finally, we investigated the prognostic significance of FOS in another HCC cohort. Patients with higher FOS expression displayed significantly shorter time to recurrence (TTR) and overall survival (OS) compared with patients with lower expression. Collectively, our study demonstrates that FOS is a potential prognostic marker for liver cancer that may reveal a novel therapeutic avenue in this lethal disease.

MiR-362-5p, Which Is Regulated by Long Non-Coding RNA MBNL1-AS1, Promotes the Cell Proliferation and Tumor Growth of Bladder Cancer by Targeting QKI

In this study, we found miR-362-5p was upregulated in bladder cancer tissues and we predicted that QKI is potential a target of miR-362-5p and MBNL1-AS1 might be able to directly target to miR-362-5p. We attempted to evaluate whether miR-362-5p could play its roles in bladder cancer through regulating QKI (quaking) and whether the expression and function of miR-362-5p could be mediated by lncRNA MBNL1-AS1. We performed the gain- and loss-function experiments to explore the association between miR-362-5p expression and bladder cancer proliferation. In vivo, the nude mice were injected with miR-362-5p knockdown SW780 cells to assess the effects of miR-362-5p on tumor growth. The results showed upregulation of miR-362-5p promoted cell proliferation of bladder cancer cells. MBNL1-AS1 and QKI could directly bind with miR-362-5p, and knockdown of MBNL1-AS1 or QKI could abrogate the regulatory effects of miR-362-5p on bladder cancer cell proliferation. Furthermore, downregulation of miR-362-5p inhibited bladder tumor growth and increased QKI expression. Our data unveiled that miR-362-5p may play an oncogenic role in bladder cancer through QKI and MBNL1-AS1 might function as a sponge to mediate the miR-362-5p expression and function.

Knockdown of lncRNAXLOC_001659 inhibits proliferation and invasion of esophageal squamous cell carcinoma cells

BACKGROUND

Studies have shown that long non-coding RNAs (lncRNAs) play a key role in almost all key physiological and pathological processes, including different types of malignant tumors. Our previous lncRNA microarray results have shown that lncRNA XLOC_001659 is upregulated in esophageal cancer (EC) tissues, with a fold change of 20.9 relative to normal esophageal tissues. But its effect and the molecular biological mechanisms on proliferation and invasion of EC cells remain unclear.

AIM

To investigate the effect of lncRNA XLOC_001659 on esophageal squamous cell carcinoma (ESCC) cells and explore the molecular biological mechanisms involved.

METHODS

RT-qPCR assay was used to quantify the expression levels of lncRNAXLOC-001659 and miR-490-5p. The proliferative capacity of the cells was determined using CCK8 and colony formation assays, and the effect of lncRNAXLOC-001659 on the invasion of ESCC cells was determined by Transwell assay. Dual-luciferase reporter assay was used to detect the target genes of lncRNAXLOC-001659 and miR-490-5p.

RESULTS

The results of RT-qPCR showed that the expression of lncRNAXLOC_001659 was upregulated in ESCC cells. CCK-8 assay showed that knockdown of lncRNAXLOC_001659 significantly inhibited ESCC cell proliferation. Colony formation and Transwell invasion assays showed that knockdown of lncRNAXLOC_001659 or overexpression of miR-490-5p significantly inhibited ESCC cell growth and invasion. Furthermore, lncRNAXLOC_001659 acts as an endogenous sponge by competitively binding to miR-490-5p to downregulate miR-490-5p. Further results confirmed that miR-490-5p targeted PIK3CA, and the recovery of PIK3CA rescued lncRNAXLOC_001659 knockdown or miR-490-5p overexpression-mediated inhibition of cell proliferation and invasion, which suggested the presence of an lncRNAXLOC_001659/miR-490-5p/PIK3CA regulatory axis.

CONCLUSION

Knockdown of lncRNA XLOC_001659 inhibits proliferation and invasion of ESCC cells via regulation of miR-490-5p/PIK3CA, suggesting that it may play a role in ESCC tumorigenesis and progression.

ERα-mediated alterations in circ_0023642 and miR-490-5p signaling suppress bladder cancer invasion

Epidemiological studies show obvious gender differences in the incidence and the prognosis of bladder cancer (BCa). Estrogen receptor alpha (ERα) was recently shown to play a protective role in BCa. However, the mechanisms by which ERα mediates BCa progression need to be further elucidated. In the present study, we explored the mechanisms by which ERα inhibits BCa invasion by modulating circRNA levels. ERα suppressed BCa invasion by decreasing circ_0023642 expression. Chromatin immunoprecipitation (ChIP) and luciferase assays revealed that ERα reduced circ_0023642 expression by regulating the expression of its host gene, UVRAG, at the transcriptional level. ERα decreased circ_0023642 levels and subsequently increased miR-490-5p expression, resulting in decreased EGFR expression to suppress BCa cell invasion. Circ_0023642 was demonstrated to directly bind to miR-490-5p. Notably, miR-490-5p regulated EGFR expression by binding to the miR-490-5p-binding site located in the 3′-untranslated region (UTR) of the EGFR mRNA. Preclinical studies using an in vivo mouse model also confirmed that this ERα/circ_0023642/miR-490-5p/EGFR signaling pathway suppressed BCa progression. Altogether, this newly identified pathway may serve as the basis for developing novel therapeutic strategies to treat BCa.

miR‑490‑5p regulates the proliferation, migration, invasion and epithelial‑mesenchymal transition of pharyngolaryngeal cancer cells by targeting mitogen‑activated protein kinase kinasekinase 9

MicroRNA (miRNA/miR) has been identified to be a promising tool in treating pharyngolaryngeal cancer. The present study aimed to investigate the role of miR‑490‑5p in the regulation of proliferation, migration, invasion and epithelial‑mesenchymal transition (EMT) of pharyngolaryngeal cancer cells. The data of miR‑490‑5p expression levels of 45 cases were obtained from the People's Hospital of Xinjiang Uygur Autonomous Region, and the prediction of the target of miR‑490‑5p was conducted by bioinformatics and verified using a luciferase assay. Cell viability was determined by cell counting kit‑8. Migration and invasion rates were measured by wound healing test and Transwell apparatus, respectively. Colony formation rate was measured by plate colony formation assay. mRNA and protein levels were determined by quantitative polymerase chain reaction and western blotting, respectively. miR‑490‑5p expression was significantly depressed in primary pharyngolaryngeal cancer tissues and cell lines, leading to an unfavorable prognosis. Evidently, miR‑490‑5p overexpression decreased the cell viabilities of BICR 18 and FaDu cells. Mechanically, miR‑490‑5p could target mitogen‑activated protein kinase kinasekinase 9 (MAP3K9). The overexpression of MAP3K9 could promote cell viability, migration and invasion rates, EMT process and ability of cloning, miR‑490‑5p could target MAP3K9 and further modulate the proliferation, migration, invasion and EMT of pharyngolaryngeal cancer cells. The results of the present study provide a novel entry point to the treatment of pharyngolaryngeal cancer.

Expression of miR-490-5p, miR-148a-3p and miR-608 in bladder cancer and their effects on the biological characteristics of bladder cancer cells

Changes in the expression of miR-490-5p, miR-148a-3p and miR-608 in bladder cancer tissues were studied. A total of 30 patients with bladder cancer who had surgical resection in the Hunan Provincial People's Hospital (Changsha, China) from April 2015 to August 2016 were selected. RT-qPCR was used to detect the expression levels of miR-490-5p, miR-148a-3p and miR-608. The expression vectors of miR-490-5p, miR-148a-3p and miR-608 were respectively transfected and divided into three groups: blank cell group, gene transfection group (groups A-C) and negative transfection group (NC group). CCK8 was used to detect cell proliferation and flow cytometry was used to detect the condition of apoptosis of each group, and the Transwell chamber was used to detect the invasion ability of the cells. After the transfection, the expression level of miR-490-5p in group A was significantly higher than that in the NC and blank groups, and the expression level of miR-148a-3p in group B was significantly higher than that in the NC and blank groups. The expression level of miR-608 in group C was significantly higher than that in the NC and blank groups (P<0.001). The survival rates of the cells in groups A-C were significantly lower than those in the NC and blank groups at 48 and 72 h (P<0.001). After the transfection, the number of invasive cells and the apoptosis rates in groups A-C were significantly higher than those in the NC and blank groups (P<0.05). miR-490-5p, miR-148a-3p and miR-608 promoted proliferation of bladder cancer T24 cells and inhibited apoptosis of the cells and showed potential to become a new target for the future treatment of bladder cancer.

Long non-coding RNA PCAT-1 promotes tumor progression by inhibiting miR-129-5p in human ovarian cancer

INTRODUCTION

Ovarian cancer (OC) is one of the most common malignancies and the leading cause of cancer-related death among women. The long non-coding RNA Prostate cancer-associated transcript-1 (PCAT-1) has been reported to play important roles in multiple human cancers. However, the role of PCAT-1 in OC has never been investigated. The purpose of this study was to investigate the expression and roles of PCAT-1 in OC.

MATERIAL AND METHODS

Expression of PCAT-1 and miR-129-5p in OC tissues and cell lines was determined by qRT-PCR. Cell proliferation and apoptosis were analyzed by MTT assay and flow cytometry, respectively. The interaction between PCAT-1 and miR-129-5p was demonstrated by luciferase reporter assay.

RESULTS

PCAT-1 is significantly upregulated in OC tissues and cell lines (p < 0.05). Overexpression of PCAT-1 promotes proliferation of OC cells and inhibits their apoptosis (p < 0.05). In addition, miR-129-5p is markedly downregulated in OC and its level is inversely correlated with PCAT-1 expression in OC tumor tissues (p < 0.05). miR-129-5p inhibits proliferation and induces apoptosis in OC cell lines (p < 0.05). Furthermore, it has been demonstrated that miR-129-5p is directly targeted by PCAT-1 and miR-129-5p overexpression can effectively attenuate the effects of PCAT-1 on the proliferation and apoptosis of OC cells.

CONCLUSIONS

Our results suggest that PCAT-1 functions as an oncogene by inhibiting miR-129-5p in OC and silencing PCAT-1 may be a novel therapeutic strategy in the treatment of OC.

Mir-26b inhibits growth and resistance to paclitaxel chemotherapy by silencing the CDC6 gene in gastric cancer

INTRODUCTION

Gastric cancer is one of the most common cancers of the digestive system and is associated with high morbidity and mortality. The aim of this study was to investigate whether miR-26b is involved in the proliferation and resistance to paclitaxel chemotherapy in gastric cancer cells.

MATERIAL AND METHODS

The expression of miR-26b in gastric cancer cell lines was determined by quantitative real-time PCR. Bioinformatics software was used to predict potential target genes of miR-26b. Luciferase assay was used to verify the interactions between target genes and miR-26b. CDC6 protein expression was measured by Western blot. The proliferation and chemotherapy resistance were analyzed by MTT assay. Cell invasion was evaluated by Transwell assay.

RESULTS

MiR-26b was down-regulated in gastric cancer cell lines compared to normal control cells, and its expression in drug resistance cells was even lower (p < 0.05). CDC6 was identified as a potential target gene of miR-26b by using bioinformatics analysis software. The expression of CDC6 was inhibited by miR-26b both at RNA level, which was determined by luciferase assay, and at protein level, which was determined by Western blot (p < 0.05). Silencing CDC6 inhibited cell proliferation, invasion, and promoted apoptosis of gastric cancer cell lines, BGC823 and SGC7901 (p < 0.05). Moreover, CDC6 knockdown inhibited chemotherapy resistance to paclitaxel, IC50 to paclitaxel decreased from 153.17 ±0.49 μg/l to 39.81 ±0.28 μg/l (p < 0.05).

CONCLUSIONS

miR-26b inhibits growth and resistance to paclitaxel chemotherapy by silencing the CDC6 gene in the gastric cancer cell line SGC7901.

Joint testing and false discovery rate control in high-dimensional multivariate regression

Multivariate regression with high-dimensional covariates has many applications in genomic and genetic research, in which some covariates are expected to be associated with multiple responses. This paper considers joint testing for regression coefficients over multiple responses and develops simultaneous testing methods with false discovery rate control. The test statistic is based on inverse regression and bias-corrected group lasso estimates of the regression coefficients and is shown to have an asymptotic chi-squared null distribution. A row-wise multiple testing procedure is developed to identify the covariates associated with the responses. The procedure is shown to control the false discovery proportion and false discovery rate at a prespecified level asymptotically. Simulations demonstrate the gain in power, relative to entrywise testing, in detecting the covariates associated with the responses. The test is applied to an ovarian cancer dataset to identify the microRNA regulators that regulate protein expression.

Hsa_circ_0103809 promotes cell proliferation and inhibits apoptosis in hepatocellular carcinoma by targeting miR-490-5p/SOX2 signaling pathway

BACKGROUND

Circular RNAs (circRNAs) represent a class of non-coding RNAs that are emerging as important regulators during tumorigenesis and provide potential targets for cancer intervention. However, the expression profiles and functions of circRNAs in hepatocellular carcinoma (HCC) have not been completely clarified. Herein, the role of hsa_circ_0103809 was investigated in HCC tissues and cell lines.

METHODS

High-throughput circRNA sequencing was performed to detect the expression profiles of circRNA in HCC tissues. The CCK-8, wound healing and flow cytometry were performed to measure the cell viability, migration and apoptosis in HCC cells. The expression levels of gene and protein in HCC tissues and cell lines were assayed by RT-qPCR and western blotting, respectively. Immunohistochemical staining was used to assess the protein expression of SOX2 in HCC tissues.

RESULTS

We discovered that hsa_circ_0103809 was significantly increased in HCC tissues and cell lines. Knockdown of hsa_circ_0103809 inhibited proliferation and migration and induced apoptosis in HCC cell lines. Investigation to the molecular mechanisms of hsa_circ_0103809 in HCC cells had revealed that hsa_circ_0103809 directly suppressed miR-490-5p, which targeted to the 3'-UTR of SOX2. Hsa_circ_0103809 loss-of-function could increase the expression of miR-490-5p as well as decreased the expression of SOX2. Furthermore, we found that si-0103809 induced growth and migration inhibition and apoptosis could be reversed by transfected with miR-490-5p inhibitors or SOX2 in HCC cells.

CONCLUSION

Our findings suggested that hsa_circ_0103809 might facilitate HCC malignant progression, at least partially, by regulating miR-490-5p/SOX2 signaling pathway.

c-Fos over-expression promotes radioresistance and predicts poor prognosis in malignant glioma

c-Fos is a major component of activator protein (AP)-1 complex. It has been implicated in cell differentiation, proliferation, angiogenesis, invasion, and metastasis. To investigate the role of c-Fos in glioma radiosensitivity and to understand the underlying molecular mechanisms, we downregulated c-Fos gene expression by lentivirus-mediated shRNA in glioma cell lines and subsequently analyzed the radiosensitivity, DNA damage repair capacity, and cell cycle distribution. Finally, we explored its prognostic value in 41 malignant glioma patients by immunohistochemistry. Our results showed that silencing c-Fos sensitized glioma cells to radiation by increasing radiation-induced DNA double strand breaks (DSBs), disturbing the DNA damage repair process, promoting G2/M cell cycle arrest, and enhancing apoptosis. c-Fos protein overexpression correlated with poor prognosis in malignant glioma patients treated with standard therapy. Our findings provide new insights into the mechanism of radioresistance in malignant glioma and identify c-Fos as a potentially novel therapeutic target for malignant glioma patients.

Identification of differentially expressed genes and biological pathways in bladder cancer

The purpose of the present study was to identify key genes and investigate the related molecular mechanisms of bladder cancer (BC) progression. From the Gene Expression Omnibus database, the gene expression dataset GSE7476 was downloaded, which contained 43 BC samples and 12 normal bladder tissues. GSE7476 was analyzed to screen the differentially expressed genes (DEGs). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed for the DEGs using the DAVID database, and a protein-protein interaction (PPI) network was then constructed using Cytoscape software. The results of the GO analysis showed that the upregulated DEGs were significantly enriched in cell division, nucleoplasm and protein binding, while the downregulated DEGs were significantly enriched in ‘extracellular matrix organization’, ‘proteinaceous extracellular matrix’ and ‘heparin binding’. The results of the KEGG pathway analysis showed that the upregulated DEGs were significantly enriched in the ‘cell cycle’, whereas the downregulated DEGs were significantly enriched in ‘complement and coagulation cascades’. JUN, cyclin-dependent kinase 1, FOS, PCNA, TOP2A, CCND1 and CDH1 were found to be hub genes in the PPI network. Sub-networks revealed that these gene were enriched in significant pathways, including the ‘cell cycle’ signaling pathway and ‘PI3K-Akt signaling pathway’. In summary, the present study identified DEGs and key target genes in the progression of BC, providing potential molecular targets and diagnostic biomarkers for the treatment of BC.

Dysregulation of miRNAs in bladder cancer: altered expression with aberrant biogenesis procedure

Aberrant expression profiles of miRNAs are widely observed in the clinical tissue specimens and urine samples as well as the blood samples of bladder cancer patients. These profiles are closely related to the pathological features of bladder cancer, such as the tumour stage/grade, metastasis, recurrence and chemo-sensitivity. MiRNA biogenesis forms the basis of miRNA expression and function, and its dysregulation has been shown to be essential for variations in miRNA expression profiles as well as tumourigenesis and cancer progression. In this review, we summarize the up-to-date and widely reported miRNAs in bladder cancer that display significantly altered expression. We then compare the miRNA expression profiles among three different sample types (tissue, urine and blood) from patients with bladder cancer. Moreover, for the first time, we outline the dysregulated miRNA biogenesis network in bladder cancer from different levels and analyse its possible relationship with aberrant miRNA expression and the pathological characteristics of the disease.

Potential targets and clinical value of miR-490-5p in hepatocellular carcinoma: a study based on TCGA, qRT-PCR and bioinformatics analyses

OBJECTIVE

To explore potential targets and clinical value of miR-490-5p in the oncogenesis and progression of hepatocellular carcinoma (HCC).

METHODS

Clinical value of miR-490-5p was accessed through The Cancer Genome Atlas (TCGA) and qRT-PCR analyses. Potential target mRNAs of miR-490-5p were predicted by bioinformatics methods and were annotated as Gene Ontology (GO) function analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway analysis, and Protein-Protein Interaction (PPI) network analysis.

RESULTS

miR-490 expression in HCC tissues was lower compared with normal control tissues based on TCGA and down regulation of miR-490-5p was verified by qRT-PCR (P<0.0001). Both miR-490 and miR-490-5p had moderate ability to diagnose HCC tissues from noncancerous tissues. Moreover, lower miR-490 level predicted poorer overall survival in patients with HCC (P=0.0063). One hundred and eighty-four mRNAs were selected as potential targets of miR-490-5p by overlap with 4,090 prediction genes and 1,478 differentially expressed genes (DEGs). Gene Ontology (GO) function analysis showed that the most significant terms were vasculature development, endoplasmic reticulum, and protein binding in biological process (BP), cellular component (CC), and molecular function (MF). In KEGG signaling pathway analysis, the statistically significant terms were lysosome, focal adhesion, glioma. In PPI network analysis, SRC, SRP9, PDGFRB, RPL28, and RPS23 were identified as the hub genes.

CONCLUSION

miR-490-5p is down-regulated in HCC and may be a prospectively diagnostic and prognostic biomarker. Moreover, miR-490-5p might directly target SRC, SRP9, PDGFRB, RPL28, or RPS23 and play an important role in HCC.

MiR-490-5p Suppresses Cell Proliferation and Invasion by Targeting BUB1 in Hepatocellular Carcinoma Cells

OBJECTIVE

To verify that miR-490-5p could influence hepatocellular carcinoma (HCC) cells' proliferation, invasion, cycle, and apoptosis by targeting BUB1.

METHODS

Quantitative real time-PCR (QRT-PCR) was used to determine the miR-490-5p expression. Immunohistochemistry, qRT-PCR, and Western blot were employed to detect BUB1 and transforming growth factor-beta (TGFβ/Smad) signaling-related proteins expression in hepatic tissues and cells. The luciferase assay was used to confirm the targeting relationship between miR-490-5p and BUB1. The Cell Counting Kit-8, colony formation, Transwell invasion, scratch healing assays, and flow cytometry analysis were conducted to evaluate HCC cells proliferation, invasion, migration, and apoptosis alteration after transfection.

RESULTS

In HCC tissues and cells, lower expression of miR-490-5p was detected, while BUB1 was overexpressed than controls. The upregulation of miR-490-5p inhibited BUB1 expression and the overexpression of miR-490-5p or the under-expression of BUB1 inhibited HCC cells proliferation, migration, invasion, and increased the apoptosis rate.

CONCLUSION

MiR-490-5p could regulate TGFβ/Smad signaling pathways by inhibiting BUB1, which could then inhibit HCC cells proliferation, invasion, and migration as well as decrease cell viability and increase apoptosis.

Understanding the Role of Non-Coding RNAs in Bladder Cancer: From Dark Matter to Valuable Therapeutic Targets

The mortality and morbidity that characterize bladder cancer compel this malignancy into the category of hot topics in terms of biomolecular research. Therefore, a better knowledge of the specific molecular mechanisms that underlie the development and progression of bladder cancer is demanded. Tumor heterogeneity among patients with similar diagnosis, as well as intratumor heterogeneity, generates difficulties in terms of targeted therapy. Furthermore, late diagnosis represents an ongoing issue, significantly reducing the response to therapy and, inevitably, the overall survival. The role of non-coding RNAs in bladder cancer emerged in the last decade, revealing that microRNAs (miRNAs) may act as tumor suppressor genes, respectively oncogenes, but also as biomarkers for early diagnosis. Regarding other types of non-coding RNAs, especially long non-coding RNAs (lncRNAs) which are extensively reviewed in this article, their exact roles in tumorigenesis are—for the time being—not as evident as in the case of miRNAs, but, still, clearly suggested. Therefore, this review covers the non-coding RNA expression profile of bladder cancer patients and their validated target genes in bladder cancer cell lines, with repercussions on processes such as proliferation, invasiveness, apoptosis, cell cycle arrest, and other molecular pathways which are specific for the malignant transformation of cells.

MicroRNA-497 upregulation inhibits cell invasion and metastasis in T24 and BIU-87 bladder cancer cells

Previous studies have reported the crucial role of microRNAs (miRNAs) in the biology and tumorigenesis of various types of cancer, including bladder cancer. The present study aimed to investigate the importance of miRNA (miR)‑497 on the pathogenesis of bladder cancer. A total of 50 patients diagnosed with bladder cancer were enrolled in the current study. The expression levels of miR‑497 in the cancerous and the adjacent noncancerous tissues were detected using reverse transcription‑quantitative polymerase chain reaction. The association between miR‑497 expression and various parameters, including age, tumor‑node‑metastasis (TNM) stage and pathological classification was determined. An miR‑497‑overexpressing vector was transfected into the T24 and BIU‑87 bladder cancer cell lines in order to determine the effect of miR‑497 expression on cell migration and invasion using Transwell assays. Additionally, the cell migration and invasion‑associated protein expression levels were also analyzed using western blotting. The findings of the present study revealed that miR‑497 was expressed at low levels in the cancer bladder tissue compared with the adjacent noncancerous tissue, and its expression was associated with the pathological classification, TNM stage and metastasis. Additionally, miR‑497 overexpression significantly reduced the number of migrated and invasive T24 and BIU‑87 cells. The mRNA and protein expression levels of E‑cadherin were increased, whereas levels of vimentin and α‑smooth muscle actin were reduced following miR‑497 overexpression. The present study revealed that miR‑497 overexpression may be a suppressor of the metastasis of bladder cancer, and may have an important role in the diagnosis of bladder cancer.

Targeting miRNAs by polyphenols: Novel therapeutic strategy for cancer

In the recent years, polyphenols have gained significant attention in scientific community owing to their potential anticancer effects against a wide range of human malignancies. Epidemiological, clinical and preclinical studies have supported that daily intake of polyphenol-rich dietary fruits have a strong co-relationship in the prevention of different types of cancer. In addition to direct antioxidant mechanisms, they also regulate several therapeutically important oncogenic signaling and transcription factors. However, after the discovery of microRNA (miRNA), numerous studies have identified that polyphenols, including epigallocatechin-3-gallate, genistein, resveratrol and curcumin exert their anticancer effects by regulating different miRNAs which are implicated in all the stages of cancer. MiRNAs are short, non-coding endogenous RNA, which silence the gene functions by targeting messenger RNA (mRNA) through degradation or translation repression. However, cancer associated miRNAs has emerged only in recent years to support its applications in cancer therapy. Preclinical experiments have suggested that deregulation of single miRNA is sufficient for neoplastic transformation of cells. Indeed, the widespread deregulation of several miRNA profiles of tumor and healthy tissue samples revealed the involvement of many types of miRNA in the development of numerous cancers. Hence, targeting the miRNAs using polyphenols will be a novel and promising strategy in anticancer chemotherapy. Herein, we have critically reviewed the potential applications of polyphenols on various human miRNAs, especially which are involved in oncogenic and tumor suppressor pathways.

Effects of Herb-Partitioned Moxibustion on the miRNA Expression Profiles in Colon from Rats with DSS-Induced Ulcerative Colitis

Objective. This study explored the mechanism of herb-partitioned moxibustion (HM) on dextran sulfate sodium- (DSS-) induced ulcerative colitis (UC) from the miRNA perspective. Methods. Rats were randomly divided into 3 groups [normal control (NC) group, UC model (UC) group, and herb-partitioned moxibustion (UCHM) group]. The UC and UCHM groups were administered 4% DSS for 7 days. The UCHM group received HM at the Tianshu (bilateral, ST25). The effect of HM on UC was observed and the miRNA expression profile in the colon tissues was analyzed. Results. Compared with the UC group, the body weights were significantly higher in the UCHM group on day 14 (P < 0.001); the macroscopic colon injury scores and microscopic histopathology scores in the UCHM group decreased (P < 0.05); and there were 15 differentially expressed miRNAs in the UCHM group. The changes in miR-184 and miR-490-5p expression levels on the UC were reversed by HM intervention. Validation using qRT-PCR showed that two miRNAs expression trend was consistent with the sequencing results. Conclusion. HM at ST25 might regulate miR-184 and miR-490-5p expression, act on the transcription of their target genes to regulate inflammatory signaling pathways, and attenuate inflammation and tissue injury in the colons of rats with DSS-induced UC.

Role of mast cell-miR-490-5p in irritable bowel syndrome

AIM

To determine the functional role of miR-490-5p in mast cell proliferation and apoptosis, and in the mast cell tryptase/PAR-2 signal pathway.

METHODS

The 3^rd generation of lentivirus vector systems containing enhanced green fluorescent protein (EGFP) (Ruisai Inc., Shanghai, China), which acts as a reporter gene was used to construct the mmu-miR-490-5p lentivirus expression vector pEGFP-antagomiR-490-5p, and the lentivirus vector pEGFP-negative was used as a negative control. The stably transfected mast cell line p815 was then constructed. GFP positive cells were successfully transfected cells. We determined the expression of miR-490-5p in p815 mast cells before and after transfection using quantitative real-time PCR (qRT-PCR). In addition, after transduction with the lentivirus vectors, the role of miR-490-5p in mast cell proliferation and apoptosis was investigated using the CCK-8 assay and flow cytometry, respectively. The mRNA levels of tryptase and PAR-2 were detected by qRT-PCR and the protein levels were detected by Western blot.

RESULTS

The inhibition of miR-490-5p expression promoted apoptosis and inhibited proliferation of p815 mast cells. The mRNA levels of tryptase and PAR-2 were significantly increased after transfection compared with the control group, tryptase (P = 0.721, normal vs null; P = 0.001, siRNA vs normal; P = 0.002, siRNA vs null) and PAR-2 (P = 0.027, siRNA vs null; P = 0.353, normal vs null; P = 0.105, siRNA vs normal). The protein levels of tryptase and PAR2 were slightly higher in the siRNA group than those in the control group, but the difference was not statistically significant (P > 0.05).

CONCLUSION

miR-490-5p plays a vital role in the pathogenesis of irritable bowel syndrome by affecting mast cell proliferation and apoptosis; with down-regulation of miR-490-5p, the mRNA level of mast cell tryptase and PAR-2 increased, and the protein level increased, but the difference was not statistically significant.

MiR-4295 promotes cell growth in bladder cancer by targeting BTG1

microRNAs (miRNAs) have been demonstrated to contribute to tumor progression and metastasis, and have been proposed to be key regulators of diverse biological processes. In this study, we report that miR-4295 is deregulated in bladder cancer tissues and cell lines. To characterize the role of miR-4295 in bladder cancer cells, we performed functional assays. The overexpression of miR-4295 significantly promoted bladder cancer cell proliferation, colony formation, and migration. Moreover, its downregulation induced cell cycle arrest and apoptosis of bladder cancer cells. Furthermore, a luciferase reporter assay and rescue experiment indicated that miR-4295 directly targets BTG1 by binding its 3'UTR. In conclusion, these results demonstrate that miR-4295 acts as an oncogene and may be a potential biomarker for bladder cancer diagnosis and treatment.

Comprehensive investigation of aberrant microRNA profiling in bladder cancer tissues

There has been accumulative evidence that microRNAs (miRNAs) play essential roles in the tumorigenesis and progression of bladder cancer. However, individual studies and small sample size caused discrepant outcomes. Thus, the current study focused on a comprehensive profiling of all differentially expressed miRNAs in a total of 519 bladder cancer tissue samples, based on miRNA microarray data. Altogether, 11 prioritized miRNAs stated by 21 published microarray datasets, including five down-regulated (miR-133a-3p, miR-1-3p, miR-99a-5p, miR-490-5p, and miR-133b) and six up-regulated candidate miRNAs (miR-182-5p, miR-935, miR-518e-3p, miR-573, miR-100-3p, and miR-3171) were analyzed with vote-counting strategy and a Robust Rank Aggregation method. Subsequently, miRNA in silico target prediction and potential pathway enrichment analysis were performed to investigate the prospective molecular mechanism of miRNAs in the tumorigenesis of bladder cancer. We found that most of the relative pathways of the aberrantly expressed miRNAs found in the current study were closely correlated with different biological processes, cellular components, molecular functions, cancer pathogeneses, and some cell signalings, such as Wnt signaling, insulin/IGF, PI3 kinase, and FGF signaling pathways. Hence, a comprehensive overview on the miRNA expression pattern in bladder cancer tissues was gained by the current study. These miRNAs might be involved in the tumorigenesis and deterioration of bladder cancer.

MicroRNA-490 inhibits tumorigenesis and progression in breast cancer

MicroRNAs are consistently reported to regulate gene expression in all cancer cell types by modulating a wide range of biological processes, including cell proliferation, differentiation, and apoptosis, which are associated with tumor development and progression. Previous studies have revealed that miR-490-3p regulates cell proliferation and apoptosis in cancers, such as hepatocellular carcinoma, lung cancer, bladder cancer, and ovarian carcinoma. In this study, we explored the hitherto unrevealed role of miR-490-3p in breast cancer. We tested miR-490-3p expression in breast cancer tissue and paracarcinoma tissue using reverse transcription-polymerase chain reaction. We also transfected the human breast cancer cell lines MCF-7 and T47D with miR-490-3p; subsequently, we determined the cell phenotype and the expression of Ras homolog gene family member A (RhoA), Bcl-xL, matrix metalloproteinase-9, and P70S6K (P70S6 kinase). Dual-luciferase reporter assay and a xenograft mouse model were used to reveal the roles of miR-490-3p and its target gene RHOA. We found that the levels of miR-490-3p were lower in the breast cancer tissue than in the paracarcinoma tissues. The overexpression of miR-490-3p suppressed breast cancer cell proliferation and promoted early stage apoptosis. Western blotting results revealed that the miR-490-3p overexpression reduced RhoA, Bcl-XL, matrix metalloproteinase-9, and P70S6K protein expression. The dual-luciferase reporter assay confirmed that RhoA is a target of miR-490-3p. The xenograft mouse model confirmed that miR-490-3p overexpression suppressed tumor growth and reduced RhoA expression. Our results indicate that miR-490-3p acts as oncosuppressive microRNA to inhibit breast cancer tumorigenesis and progression by targeting RhoA directly. It may contribute to breast cancer diagnosis and treatment.

miR-490-5p suppresses tumour growth in renal cell carcinoma through targeting PIK3CA

Background Information

Dysregulated micro‐RNAs have been reported in many human cancers, including renal cell carcinoma. Recent studies indicated that miR‐490 is involved in tumour development and progression. However, the expression profile and function in renal cell carcinoma remains unknown.

Results

Herein, we showed that miR‐490‐5p was down‐regulated in renal cell carcinoma tissues and cells compared with the adjacent normal tissues and normal cells. We also provided evidence that miR‐490‐5p acts as a tumour suppressor in renal carcinoma in a variety of in vitro and in vivo assays. Mechanistically, miR‐490‐5p was verified to directly bind to 3′ UTR of the PIK3CA mRNA and reduce the expression of PIK3CA at both mRNA and protein levels, which further inhibits phosphatidylinositol 3‐kinase/Akt signalling pathway. We further showed that knockdown of PIK3CA can block the growth inhibitory effect of miR‐490‐5p, and over‐expression of PIK3CA can reverse the inhibitory effect of miR‐490‐5p on renal cancer cell tumourigenicity.

Conclusions

Taken together, our results indicated for the first time that miR‐490‐5p functions as a tumour suppressor in renal carcinoma by targeting PIK3CA.

Significance

Our findings suggest that miR‐490‐5p may be a potential gene therapy target for the treatment of renal cell carcinoma.

MiR-592 represses FOXO3 expression and promotes the proliferation of prostate cancer cells

Prostate cancer (PC) is a serious health problem all over the world. Cell proliferation plays a major role in the tumorigenesis of PC. It is reported that microRNAs (miRNAs) played crucial roles in the regulation of cell proliferation. However, the underlying mechanism of miRNAs in PC has not been intensively investigated. In the present study, the effect of miR-592 on the cell proliferation of PC was investigated. The results showed that miR-592 was significantly upregulated in PC cell and PC tissues. To investigate the biological roles of miR-592, we induced either the up- or downregulation of miR-592 expression by transfecting DU145 PC cells with miR-592 mimics or miR-592 inhibitor. Our results demonstrated that the upregulation of miR-592promoted cell growth, while miR-592 inhibitor showed the opposite effect. Further experiment revealed that miR-592 repressed the expression of FOXO3 by directly targeting the 3'UTR of the FOXO3 transcript, which resulted in upregulating of the expression of cyclin D1 and downregulating of the expression of p21. In sum, our data indicated a novel aspect of the miR-592 in the molecular etiology of PC.