miR-501 acts as an independent prognostic factor that promotes the epithelial-mesenchymal transition through targeting JDP2 in hepatocellular carcinoma

Comprehensive analysis of differentially expressed miRNAs in hepatocellular carcinoma: Prognostic, predictive significance and pathway insights

Robust prognostic and predictive factors for hepatocellular carcinoma, a leading cause of cancer-related deaths worldwide, have not yet been identified. Previous studies have identified potential HCC determinants such as genetic mutations, epigenetic alterations, and pathway dysregulation. However, the clinical significance of these molecular alterations remains elusive. MicroRNAs are major regulators of protein expression. MiRNA functions are frequently altered in cancer. In this study, we aimed to explore the prognostic value of differentially expressed miRNAs in HCC, to elucidate their associated pathways and their impact on treatment response. To this aim, bioinformatics techniques and clinical dataset analyses were employed to identify differentially expressed miRNAs in HCC compared to normal hepatic tissue. We validated known associations and identified a novel miRNA signature with potential prognostic significance. Our comprehensive analysis identified new miRNA-targeted pathways and showed that some of these protein coding genes predict HCC patients' response to the tyrosine kinase inhibitor sorafenib.

Palmitic acid-induced microRNA-143-5p expression promotes the epithelial-mesenchymal transition of retinal pigment epithelium via negatively regulating JDP2

BACKGROUND

The epithelial-mesenchymal transition (EMT) of retinal pigment epithelial (RPE) cells is the most crucial step in the etiopathogenesis of proliferative vitreoretinopathy. This study aimed to investigate the role of miR-143-5p in the EMT of RPE cells induced by palmitic acid (PA).

METHODS

ARPE-19 cells were treated with PA to induce EMT, followed by E-cadherin and α-smooth muscle actin (α-SMA) expression and the microRNA expression profile analyses. Subsequently, miR-143-5p mimics/inhibitors, and plasmids expressing its predicted target gene c-JUN-dimerization protein 2 (JDP2), were transfected in ARPE-19 cells using lipofectamine 3000, and followed by PA treatment. Their impacts on EMT were explored using wound healing and Western blot assays. Additionally, miR-143-5p mimics and JDP2-expressing plasmid were co-transfected into ARPE-19 cells and treated with PA to explore whether PA induced EMT of ARPE-19 cells via the miR-143-5p/JDP2 axis.

RESULTS

PA decreased E-cadherin expression and increased those of α-SMA and miR-143-5p. Inhibiting miR-143-5p suppressed the migration of ARPE-19 cells and altered the expressions of E-cadherin and α-SMA. However, additional PA treatment attenuated these alterations. JDP2 was a target of miR-143-5p. Overexpression of JDP2 inhibited the EMT of ARPE-19 cells, resulting in α-SMA downregulation and E-cadherin upregulation, which were reversed by additional PA treatment via inhibiting JDP2 expression. Overexpression of miR-143-5p reversed the effect of JDP2 on the EMT of ARPE-19 cells and additional PA treatment markedly enhanced the effect of miR-143-5p mimics.

CONCLUSION

PA promotes EMT of ARPE-19 cells via regulating the miR-143-5p/JDP2 axis, and these findings provide significant insights into the potential targeting of this axis to treat proliferative vitreoretinopathy.

The role and application of transcriptional repressors in cancer treatment

Gene expression is modulated through the integration of many regulatory elements and their associated transcription factors (TFs). TFs bind to specific DNA sequences and either activate or repress transcriptional activity. Through decades of research, it has been established that aberrant expression or functional abnormalities of TFs can lead to uncontrolled cell division and the development of cancer. Initial studies on transcriptional regulation in cancer have focused on TFs as transcriptional activators. However, recent studies have demonstrated several different mechanisms of transcriptional repression in cancer, which could be potential therapeutic targets for the development of specific anti-cancer agents. In the first section of this review, "Emerging roles of transcriptional repressors in cancer development," we summarize the current understanding of transcriptional repressors and their involvement in the molecular processes of cancer progression. In the subsequent section, "Therapeutic applications," we provide an updated overview of the available therapeutic targets for drug discovery and discuss the new frontier of such applications.

Bioinformatics Methods Reveal the Biomarkers and the miRNA-mRNA Network in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) has threatened the health of humans, and few therapeutic strategies can completely uproot this illness. Bioinformatics methods have been widely used for investigating the pathological mechanisms of disease. In this study, datasets including GSE20077 and GSE108724, obtained from the Gene Expression Omnibus (GEO) database, were used for investigating the biomarker and molecular mechanism of HCC. The differentially expressed genes (DEGs) in the datasets were identified, and the targets of the miRNAs were searched in the miRDIP and miRNET databases. Enrichment analysis was performed for delving the molecular mechanism of DEGs, and protein-protein interaction (PPI) networks and miRNA-mRNA networks were used to reveal the hub nodes and the related interaction relationships. Moreover, the expression and diagnostic values of hub nodes were analyzed with the GEPIA2 database. The results showed that 53 upregulated miRNAs and 48 downregulated miRNAs were found in GSE20077, and 55 upregulated miRNAs and 69 downregulated miRNAs were found in GSE108724. Moreover, seven common miRNAs including miR-146b-5p, miR-338-3p, miR-375, miR-502-3p, miR-532-3p, miR-532-5p, and miR-557 were found in the datasets. The targets of the common miRNAs were related with the P53, HIF1, Wnt, and NF-κB pathways. Besides, YWHAZ and CDC42 were identified as the hub nodes and served as the downstream targets of miR-375-3p. The GEPIA2 database showed that YWHAZ and CDC42 were related with the survival rate of the patients. In conclusion, this study suggests that miR-375-3p functions as a tumor suppressor which could inhibit the progression of HCC via targeting YWHAZ and CDC42.

Biological Functions and Prognostic Value of Ferroptosis-Related Genes in Bladder Cancer

Background: Every year, nearly 170,000 people die from bladder cancer worldwide. A major problem after transurethral resection of bladder tumor is that 40–80% of the tumors recur. Ferroptosis is a type of regulatory necrosis mediated by iron-catalyzed, excessive oxidation of polyunsaturated fatty acids. Increasing the sensitivity of tumor cells to ferroptosis is a potential treatment option for cancer. Establishing a diagnostic and prognostic model based on ferroptosis-related genes may provide guidance for the precise treatment of bladder cancer.

Methods: We downloaded mRNA data in Bladder Cancer from The Cancer Genome Atlas and analyzed differentially expressed genes based on and extract ferroptosis-related genes. We identified relevant pathways and annotate the functions of ferroptosis-related DEGs using Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis and Gene Ontology functions. On the website of Search Tool for Retrieving Interacting Genes database (STRING), we downloaded the protein-protein interactions of DEGs, which were drawn by the Cytoscape software. Then the Cox regression analysis were performed so that the prognostic value of ferroptosis-related genes and survival time are combined to identify survival- and ferroptosis-related genes and establish a prognostic formula. Survival analysis and receiver operating characteristic curvevalidation were then performed. Risk curves and nomograms were generated for both groups to predict survival. Finally, RT-qPCR was applied to analyze gene expression.

Results: Eight ferroptosis-related genes with prognostic value (ISCU, NFE2L2, MAFG, ZEB1, VDAC2, TXNIP, SCD, and JDP2) were identified. With clinical data, we established a prognostic model to provide promising diagnostic and prognostic information of bladder cancer based on the eight ferroptosis-related genes. RT-qPCR revealed the genes that were differentially expressed between normal and cancer tissues.

Conclusion: This study found that the ferroptosis-related genes is associated with bladder cancer, which may serve as new target for the treatment of bladder cancer.

MicroRNA signature in liver cancer

Liver cancer is the 7^th utmost frequent neoplasm and the 4^th principal source of cancer deaths. This malignancy is linked with several environmental and lifestyle-related factors emphasizing the role of epigenetics in its pathogenesis. MicroRNAs (miRNAs) have been regarded as potent epigenetic mechanisms partaking in the pathogenesis of liver cancer. Dysregulation of miRNAs has been related with poor outcome of patients with liver cancer. In the current manuscript, we provide a concise review of the results of recent studies about the role of miRNAs in the progression of liver cancer and their diagnostic and prognostic utility.

M2 macrophages-derived exosomal microRNA-501-3p promotes the progression of lung cancer via targeting WD repeat domain 82

Background

Exosomes are known to transmit microRNAs (miRNAs) to affect cancer progression, while the role of M2 macrophages-derived exosomes (M2 exosomes) conveying miR-501-3p in lung cancer (LC) remains unknown. We aim to explore the role of exosomal miR-501-3p in LC development via targeting WD repeat domain 82 (WDR82).

Methods

Lung cancer tissue and normal tissue specimens were collected, in which tumor-associated macrophages (TAM) were measured by immunohistochemistry. M2 macrophages were induced and treated with altered miR-501-3p, and then the exosomes were extracted and identified. MiR-501-3p and WDR82 expression in LC tissues and cell liens was determined. The predictive role of miR-501-3p in prognosis of LC patients was assessed, and the proliferation, colony formation ability, invasion, migration and apoptosis of the LC cells were determined. Targeting relationship between miR-501-3p and WDR82 was confirmed.

Results

TAM level was elevated in lung cancer tissues. MiR-501-3p was upregulated while WDR82 was downregulated in LC tissues and cell lines, and the M2 exosomes further upregulated miR-501-3p. M2 exosomes and exosomal miR-501-3p promoted LC cell growth. MiR-501-3p inhibition reversed the effect of M2 exosomes on LC cells. WDR82 was confirmed as a target gene of miR-501-3p.

Conclusion

M2 macrophages-derived exosomal miR-501-3p promotes the progression of LC via downregulating WDR82.

Down-regulated lncRNA AGAP2-AS1 contributes to pre-eclampsia as a competing endogenous RNA for JDP2 by impairing trophoblastic phenotype

Recently, growing evidence has shown that aberrant long non‐coding RNA (lncRNA) expression in conjunction with an impaired trophoblastic phenotype could implicate the pathological process of pre‐eclampsia (PE). However, only a small portion of lncRNAs has been characterized with regard to the function and molecular mechanisms involved in PE. There are still gaps in the available knowledge; as a result, there are currently only a few applicable treatments for PE in the context of lncRNA. Here, we found that lncRNA AGAP2‐AS1 is abnormally down‐regulated in severe PE placenta tissues. Using human trophoblasts, we established that AGAP2‐AS1 knockdown could inhibit trophoblasts proliferation and invasion and promote cell apoptosis. Further, we showed that overexpression of AGAP2‐AS1 substantially stimulated the development of the trophoblastic phenotype. Through high‐throughput sequencing analysis, we demonstrated that silencing of AGAP2‐AS1 favourably regulated various genes which are relevant to trophoblastic growth and invasion. Mechanistically, AGAP2‐AS1 promoted the suppressor protein, Jun dimerization protein 2 (JDP2), by sponging miR‐574‐5p. Resultantly, further impairment of the trophoblastic phenotype was achieved by way of inhibiting cell growth, apoptosis and invasion. We also determined that the expression of AGAP2‐AS1 could be mediated by FOXP1. Our results showed that the down‐regulated expression of lncRNA AGAP2‐AS1 might serve as a key suppressor in PE via inhibition of JDP2 at the post‐transcriptional level by competing for miR‐574; thus, this presents a novel therapeutic strategy for PE.

miR-939-3p promotes epithelial-mesenchymal transition and may be used as a prognostic marker in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common types of cancer worldwide with a high morbidity and mortality rate. An increasing number of studies have demonstrated that microRNAs (miRNAs) serve an important role in HCC. The present study investigated the role of miR-939-3p in HCC. It was demonstrated that miR-939-3p was upregulated in HCC cell lines and HCC tissues compared with normal liver cell lines and paired normal tissues, respectively. It was also found that upregulation of miR-939-3p expression levels in HCC tissues was associated with a less favorable prognosis. Moreover, the overexpression of miR-939-3p in LM3 cells enhanced the metastatic capacity of these cells and promoted epithelial-mesenchymal transition (EMT). In contrast, miR-939-3p inhibition decreased the invasive capacity of HCC cells and EMT. Potential binding target of miR-939-3p to estrogen receptor 1 (ESR1) were predicted using TargetScan. The expression levels of miR-939-3p were negatively associated with ESR1 in HCC tissues based on data from The Cancer Genome Atlas. A luciferase reporter assay was used to confirm ESR1 as a direct downstream target of miR-393-3p. The miR-939-3p/ESR1 axis may be a potential novel target for the treatment of HCC.