miR-592/WSB1/HIF-1α axis inhibits glycolytic metabolism to decrease hepatocellular carcinoma growth

HNRNPL Increases WSB1 mRNA Stability to Promote Proliferation and Lipid Droplets in Clear Cell Renal Cell Carcinoma

This study aims to explore the possible effect and mechanism of heterogeneous nuclear ribonucleoprotein L (HNRNPL) on the lipid droplet and proliferation ability of clear cell renal cell carcinoma (ccRCC). The mRNA and protein expressions of HNRNPL and WSB1 on ccRCC tissues and cells were detected using qRT-PCR and western blot. The lipid droplet of cells was assessed after Oil Red O staining and BODIPY 493/503 staining. Cell proliferation was detected by CCK-8 assay. The interaction between HNRNPL and WSB1 was verified using RNA immunoprecipitation (RIP) and RNA-pull down assay. WSB1 mRNA stability was measured by Actinomycin D. Elevated expressions of HNRNPL and WSB1 were found in both ccRCC tissues and cells. HNRNPL knockdown can lead to suppressed lipid droplet and cell proliferation ability of ccRCC cells, while expression pattern was found in cells with HNRNPL overexpression. RIP and RNA-pull down assay clarified the binding of HNRNPL with WSB1. HNRNPL can facilitate the stability and expression of WSB1 mRNA. Rescue assay identified the promotive effect of HNRNPL on lipid droplets and cell proliferation of ccRCC cells can be abolished in response to WSB1 knockdown. Collected evidence summarized that HNRNPL can increase the stability of WSB1 mRNA to promote lipid droplet and proliferation ability in ccRCC cells.

Circulating microRNAs improve bacterial infection diagnosis and overall survival prediction in acute decompensation of liver cirrhosis

Bacterial infections are the most frequent precipitating event in patients with acute decompensation of cirrhosis (AD) and are associated with high mortality. Early diagnosis is challenging due to cirrhosis-related systemic inflammation. Here we investigated the potential of circulating microRNAs to diagnose bacterial infections and predict survival in cirrhotic patients with AD. High throughput profiling of circulating microRNAs was performed using the Nanostring technology in 57 AD patients and 24 patients with compensated cirrhosis (CC). Circulating miRs profiling showed that: (a) miRs differentially detected in AD vs. CC were mostly down-regulated; (b) a composite score including absolute neutrophil count, C reactive protein and miR-362-3p could diagnose bacterial infection with an excellent performance (AUC of 0.825 [95% CI = 0.671-0.980; p < 0.001]); (c) a composite score including miR-382-5p, miR-592 and MELD-Na improved 6-month survival prediction. Circulating miRs are strongly dysregulated in patients with AD and may help to improve bacterial infection diagnosis and survival prediction.

MicroRNA-592 Inhibits the Growth of Ovarian Cancer Cells by Targeting ERBB3

Objectives: Ovarian cancer is the most lethal gynecologic malignancy, and targeted therapy for different pathological types and molecular phenotypes is urgent to be studied. Studies have shown that MicroRNA-592 (miR-592) plays an important negative regulatory role in the occurrence of gastrointestinal malignancies, breast cancer, non-small cell lung cancer, and glioma, but the expression of miR-592 in ovarian cancer and the mechanism of action are still unclear. Methods: The expressions of miR-592 were examined by RT-PCR and Western Blot. Cell viability and migratory capacity were detected by CCK-8 and transwell assay. TargetScan (http://www.targetscan.org) was analyzed to predict potential targets of miR-592. Then Dual-luciferase reporter gene assay was performed to verify the targeting relationship between miR-592 and ERBB3. A mouse xenograft model was applied to confirm the effect of miR-592. Results: In our study, we found that the expression of miR-592 is reduced in epithelial ovarian cancer tissues. The exogenous expression of miR-592 inhibits the proliferation, migration, and invasion in epithelial ovarian cancer tumor cells. Furthermore, the exogenous expression of miR-592 inhibits tumor growth in the nude mouse xenograft model. Therefore, miR-592 may play a role of tumor suppressor miRNA in the occurrence and development of ovarian cancer. Further experiments demonstrated that tumor-related ERBB3 is a target gene mediated by miRNA-592. The dual-luciferase reporter system was used to identify miRNA-592 target genes; qPCR and Western Blot were used to detect the expression of ERBB3. Mechanical experiments confirmed that miRNA-592 negatively regulated ERBB3.Conclusion: Together, these findings identify a heretofore unrecognized link between miR-592 and ERBB3 and suggest that targeting on miR-592 warrants attention as a novel and potential therapeutic strategy for ovarian cancer.

Development of a miRNA-based classifier for detection of colorectal cancer molecular subtypes

Previously, colorectal cancer (CRC) has been classified into four distinct molecular subtypes based on transcriptome data. These consensus molecular subtypes (CMSs) have implications for our understanding of tumor heterogeneity and the prognosis of patients. So far, this classification has been based on the use of messenger RNAs (mRNAs), although microRNAs (miRNAs) have also been shown to play a role in tumor heterogeneity and biological differences between CMSs. In contrast to mRNAs, miRNAs have a smaller size and increased stability, facilitating their detection. Therefore, we built a miRNA-based CMS classifier by converting the existing mRNA-based CMS classification using machine learning (training dataset of n = 271). The performance of this miRNA-assigned CMS classifier (CMS-miRaCl) was evaluated in several datasets, achieving an overall accuracy of ~ 0.72 (0.6329-0.7987) in the largest dataset (n = 158). To gain insight into the biological relevance of CMS-miRaCl, we evaluated the most important features in the classifier. We found that miRNAs previously reported to be relevant in microsatellite-instable CRCs or Wnt signaling were important features for CMS-miRaCl. Following further studies to validate its robustness, this miRNA-based alternative might simplify the implementation of CMS classification in clinical workflows.

Construction of a Necroptosis-Related miRNA Signature for Predicting the Prognosis of Patients With Hepatocellular Carcinoma

Background: Many miRNAs have been demonstrated to be associated with the prognosis of hepatocellular carcinoma (HCC). However, how to combine necroptosis-related miRNAs to achieve the best predictive effect in estimating HCC patient survival has not been explored.

Methods: The mRNA and miRNA expression profile were downloaded from a public database (TCGA-LIHC cohort). Necroptosis-related genes were obtained from previous references, and necroptosis-related miRNAs were identified using Pearson analysis. Subsequently, differential expression miRNAs (DEms) were identified in HCC and paracancer normal samples based on necroptosis-related miRNA expression. The whole set with HCC was randomized into a training set and testing set (1:1). LASSO-Cox regression analysis was used to construct an miRNA signature. Multiple statistical methods were used to validate the clinical benefit of signature in HCC patients, including receiver operator characteristic (ROC) curves, Kaplan–Meier survival analyses, and decision curve analysis (DCA). The downstream target genes of miRNAs were obtained from different online tools, and the potential pathways involved in miRNAs were explored. Finally, we conducted RT-qPCR in SK-HEP-1, THLE-3, and HUH-7 cell lines for miRNAs involved in the signature.

Results: The results showed that a total of eight specific necroptosis-related miRNAs were screened between HCC and adjacent tissues in the training set. Subsequently, based on the aforementioned miRNAs, 5-miRNA signature (miR-139-5p, hsa-miR-326, miR-10b-5p, miR-500a-3p, and miR-592) was generated by LASSO-Cox regression analysis. Multivariate Cox regression analysis showed that the risk scores were independent prognostic indicators in each set. The area under curves (AUCs) of 1 year, 3 years, 5 years, and 7 years were high in each set (AUC >0.7). DCA analysis also revealed that the risk score had a potential benefit than other clinical characteristics. Meanwhile, survival analysis showed that the high-risk group showed low survival probabilities. Moreover, the results of enrichment analysis showed that specific miRNAs were mainly enriched in the cAMP signaling pathway and TNF signaling pathway. Finally, the results of RT-qPCR were consistent with the prediction results in public databases.

Conclusion: Our study establishes a robust tool based on 5-necroptosis-related miRNAs for the prognostic management of HCC patients.

Epigenetic Regulation During Hypoxia and Its Implications in Cancer

Hypoxia is defined as a cellular stress condition caused by a decrease in oxygen below physiologically normal levels. Cells in the core of a rapidly growing solid tumor are faced with the challenge of inadequate supply of oxygen through the blood, owing to improper vasculature inside the tumor. This hypoxic microenvironment inside the tumor initiates a gene expression program that alters numerous signaling pathways, allowing the cancer cell to eventually evade adverse conditions and attain a more aggressive phenotype. A multitude of studies covering diverse aspects of gene regulation has tried to uncover the mechanisms involved in hypoxia-induced tumorigenesis. The role of epigenetics in executing widespread and dynamic changes in gene expression under hypoxia has been gaining an increasing amount of support in recent years. This chapter discusses, in detail, various epigenetic mechanisms driving the cellular response to hypoxia in cancer.

Identification of candidate targets for the diagnosis and treatment of atherosclerosis by bioinformatics analysis

Atherosclerosis, a chronic inflammatory disease, is the primary cause of most cardiovascular diseases. Circular RNAs (circRNAs) were reported to serve as post-transcriptional regulators and diagnostic markers in various diseases, but the underlying correlation between circRNAs and atherosclerosis remains elusive. In this study, we downloaded the microarray dataset GSE107522 from the Gene Expression Omnibus (GEO) and identified nine differentially expressed circRNAs (DECs). DECs expression in exosomes were investigated, and hsa_circ_0005699 was selected for subsequent analysis. We then identified 14 RNA-binding proteins (RBPs) and 71 possible hsa_circ_0005699-interacting microRNAs. Subsequently, target gene prediction and enrichment analyses were performed. The enriched pathways of RBP eIF4AIII include spliceosome, cell cycle, and pathways in cancer. We constructed a protein-protein interaction network, and 20 hub genes were identified using Search Tool for the Retrieval of Interacting Genes/Proteins and Cytoscape. Hub gene analysis revealed significant enrichment in mRNA splicing via the spliceosome, RNA splicing, protein binding, neurotrophin signaling pathway, and Ras signaling pathway. Using DrugMatrix of the Enrichr database, we identified 16 most significant small-molecule compounds that interacted with hub genes. Finally, seven hub genes (NEDD4L, FBXO44, FBXO27, WSB1, FBXW8, UBE2F, and ASB1) in cluster 1 were considered key targets associated with atherosclerosis according to MCODE analysis and the intersection between the module and hub genes. Thus, hsa_circ_0005699, RBP eIF4AIII, and the seven identified hub genes (NEDD4L, FBXO44, FBXO27, WSB1, FBXW8, UBE2F, and ASB1) could help to elucidate the pathogenesis and progression of atherosclerosis. This work may contribute to providing candidate targets for the diagnosis and treatment of atherosclerosis.

MicroRNAs as Modulators of Tumor Metabolism, Microenvironment, and Immune Response in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related mortality. Molecular heterogeneity and absence of biomarkers helping patient allocation to the best therapeutic option contribute to poor prognosis in advanced stages. MicroRNAs’ (miRNAs) deregulated expression contributes to tumor development and progression and influences drug resistance in HCC. Accordingly, miRNAs have been extensively investigated as both biomarkers and therapeutic targets. The diagnostic and prognostic roles of circulating miRNAs have been ascertained, though with some inconsistencies across studies. From a therapeutic perspective, miRNA-based approaches demonstrated safety profiles and antitumor efficacy in HCC animal models. Nevertheless, caution should be used when transferring preclinical findings to the clinic, due to possible molecular inconsistency between animal models and the heterogeneous patterns of human diseases. A wealth of information is offered by preclinical studies exploring the mechanisms driving miRNAs’ aberrant expression, the molecular cascades triggered by miRNAs and the corresponding phenotypic changes. Ex-vivo analyses confirmed these results, further shedding light on the intricacy of the human disease often overcoming pre-clinical models. This complexity seems to be ascribed to the intrinsic heterogeneity of HCC, to different risk factors driving its development, as well as to changes across stages and previous treatments. Preliminary findings suggest that miRNAs associated with specific risk factors might be more informative in defined patients’ subgroups. The first issue to be considered when trying to envisage a possible translational perspective is the molecular context that often drives different miRNA functions, as clearly evidenced by “dual” miRNAs. Concerning the possible roles of miRNAs as biomarkers and therapeutic targets, we will focus on miRNAs’ involvement in metabolic pathways and in the modulation of tumor microenvironment, to support their exploitation in defined contexts.

Critical signaling pathways governing hepatocellular carcinoma behavior; small molecule-based approaches

Hepatocellular carcinoma (HCC) is the second leading cause of death due to cancer. Although there are different treatment options, these strategies are not efficient in terms of restricting the tumor cell's proliferation and metastasis. The liver tumor microenvironment contains the non-parenchymal cells with supportive or inhibitory effects on the cancerous phenotype of HCC. Several signaling pathways are dis-regulated in HCC and cause uncontrolled cell propagation, metastasis, and recurrence of liver carcinoma cells. Recent studies have established new approaches for the prevention and treatment of HCC using small molecules. Small molecules are compounds with a low molecular weight that usually inhibit the specific targets in signal transduction pathways. These components can induce cell cycle arrest, apoptosis, block metastasis, and tumor growth. Devising strategies for simultaneously targeting HCC and the non-parenchymal population of the tumor could lead to more relevant research outcomes. These strategies may open new avenues for the treatment of HCC with minimal cytotoxic effects on healthy cells. This study provides the latest findings on critical signaling pathways governing HCC behavior and using small molecules in the control of HCC both in vitro and in vivo models.

MicroRNA‑592 promotes cell proliferation, migration and invasion in colorectal cancer by directly targeting SPARC

Colorectal cancer (CRC), one of the most common cancer types, causes a large number of cancer-related mortalities annually worldwide. Dysregulated microRNAs (miRNAs/miR) are closely associated with the malignant progression of CRC. Therefore, the present study aimed to investigate the expression and regulatory role of miR-592 in CRC. It was found that miR-592 expression was significantly elevated in CRC tissues and cell lines, and was associated with the prognosis of patients. Cellular phenotype assays demonstrated that miR-592 could promote CRC cell proliferation, migration and invasion. Bioinformatics analysis demonstrated that miR-592 mainly participated in the positive regulation of transcription, as well as the regulation of cell motility. Moreover, miR-592 targets were enriched in several signaling pathways, such as the ‘mTOR’ and ‘FoxO’ signaling pathways. In addition, secreted protein acidic and rich in cysteine (SPARC) was identified as a target of miR-592 in CRC. The present results suggested that miR-592 acts as an oncogene in CRC, in part, by directly inhibiting SPARC expression. Collectively, the present study provides a novel potential therapeutic strategy for CRC.

Therapeutic Implications of TGFβ in Cancer Treatment: A Systematic Review

Transforming growth factor β (TGFβ) is a pleiotropic cytokine that participates in a wide range of biological functions. The alterations in the expression levels of this factor, or the deregulation of its signaling cascade, can lead to different pathologies, including cancer. A great variety of therapeutic strategies targeting TGFβ, or the members included in its signaling pathway, are currently being researched in cancer treatment. However, the dual role of TGFβ, as a tumor suppressor or a tumor-promoter, together with its crosstalk with other signaling pathways, has hampered the development of safe and effective treatments aimed at halting the cancer progression. This systematic literature review aims to provide insight into the different approaches available to regulate TGFβ and/or the molecules involved in its synthesis, activation, or signaling, as a cancer treatment. The therapeutic strategies most commonly investigated include antisense oligonucleotides, which prevent TGFβ synthesis, to molecules that block the interaction between TGFβ and its signaling receptors, together with inhibitors of the TGFβ signaling cascade-effectors. The effectiveness and possible complications of the different potential therapies available are also discussed.

WSB2 as a target of Hedgehog signaling promoted the malignant biological behavior of Xuanwei lung cancer through regulating Wnt/β-catenin signaling

Background

Lung cancer represents the most leading causes of cancer-related deaths worldwide, especially in Xuanwei in eastern Yunnan province, China. WD repeat and SOCS box containing protein (WSB) has been reported to participate in the carcinogenesis of lung cancer. However, there is no report about the role of WSB2 in the carcinogenesis and development of lung cancer in Xuanwei. Here, we investigated the functional role of WSB2 in Xuanwei lung cancer and uncovered its underlying molecular mechanisms.

Methods

The expression of WSB2 in lung cancer cell lines and tissues were measured using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Western blotting was used to determine the protein levels of WSB2, E-cadherin, N-cadherin, vimentin, c-Myc and β-catenin in lung cancer cells. Cell viability was detected using 3-(4,5-diethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-etrazolium, inner salt (MTS) assay. While cell apoptosis and cell cycle distribution were quantified using flow cytometry following indicated staining. The change of cell invasion ability was detected using Transwell assay. FH535 was employed to block Wnt/β-catenin pathway. A xenograft tumor model was applied to confirm the tumor properties of WSB2 in vivo.

Results

Our data showed that WSB2 was frequently up-regulated in Xuanwei lung cancer tissues and cells, when compared with paired non-cancerous tissues and normal lung epithelial cells. Knockdown of WSB2 notably reduced cell viability, cell invasion, epithelial-mesenchymal transition (EMT) process, while induced apoptotic cell death and cell cycle arrest of Xuanwei lung cancer cells. Moreover, in vivo findings also confirmed that WSB2 knockdown could effectively delay the growth of tumor. Mechanistic studies revealed that c-Myc and β-catenin were notably decreased at both protein and mRNA levels after knocking down of WSB2, while overexpression of WSB2 showed a contrary tendency. In addition, blocking Wnt/β-catenin pathway using FH535 rescued the cancer promoting effect mediated by overexpression of WSB2. Furthermore, WSB2 activated Wnt/β-catenin pathway and accelerated the progression of lung cancer.

Conclusions

WSB2 promoted the progression of lung cancer in Xuanwei by triggering Wnt/β-catenin signaling pathway.

Non-coding RNAs: emerging regulators of glucose metabolism in hepatocellular carcinoma

Reprogramming of metabolism is one of the hallmarks of cancer, among which glucose metabolism dysfunction is the most prominent feature. The glucose metabolism of tumor cells is significantly different from that of normal cells. Glucose metabolism reprogramming of hepatocellular carcinoma (HCC) has become an important research hotspot in the field of HCC, a variety of tumor metabolic interventions have been applied clinically. Moreover, various Non-coding RNAs (ncRNAs) including microRNAs (miRNAs), long non-coding (lncRNAs) as well as circular RNAs (circRNAs), have recently been proved to play potential roles in glucose metabolism. This review summarizes the effects of ncRNAs on HCC that participate in glucose metabolism and discuss the related mechanisms to find potential and effective targeted treatments for HCC.

MicroRNA-342-5p activates the Akt signaling pathway by downregulating PIK3R1 to modify the proliferation and differentiation of vascular smooth muscle cells

Abnormal cell proliferation and invasion of vascular smooth muscle cells are among the primary causes of cardiovascular disease. Studies have shown that microRNA(miR)-342-5p participates in the development of cardiovascular diseases. The current study aimed to explore the role of miR-342-5p in the proliferation and differentiation of mouse aortic vascular smooth muscle (MOVAS) cells. MOVAS cells were transfected with miR-342-5p mimics, miR-342-5p inhibitor or their respective negative controls, and co-transfected with small interfering (si)RNA targeting phosphatidylinositol 3-kinase regulatory subunit α (PIK3R1) and miR-342-5p inhibitor. The cell proliferation of MOVAS cells was detected using the Cell Counting Kit-8, while cell migration and cell invasion were investigated using a wound healing and Transwell assays, respectively. Target genes for miR-342-5p were confirmed using reverse transcription-quantitative PCR (RT-qPCR) and dual luciferase reporter assay. The relative mRNA and protein expression levels of miR-342-5p were measured using RT-qPCR and western blot analysis. MOVAS cells were treated with a PI3K inhibitor (LY294002) to explore the role of miR-342-5p on the Akt pathway. The results revealed that miR-342-5p mimics promoted cell viability, migration and invasion, and increased the expression of vimentin and phosphorylated-Akt but reduced a-smooth muscle actin (α-SMA) and PIK3R1 expression. However, miR-342-5p inhibitor produced the opposite effects. PIK3R1 was the target gene for miR-342-5p and the effect of siPIK3R1 on MOVAS cells was similar to that of miR-342-5p mimics, while siPIK3R1 partially reversed the effect of miR-342-5p inhibitor on MOVAS cells. The Akt signaling pathway was activated by miR-342-5p mimics or siPIK3R1. Moreover, miR-342-5p mimics partially activated the Akt signaling pathway inhibited by LY294002. MiR-342-5p could promote the proliferation and differentiation of MOVAS and phenotypic transformation. The mechanism behind these processes may be associated with the activation of the Akt signaling pathway induced by PIK3R1 inhibition.

USP53 promotes apoptosis and inhibits glycolysis in lung adenocarcinoma through FKBP51-AKT1 signaling

Despite an overall decline in the incidence of new cases, lung adenocarcinoma continues to be a leading cause of cancer death worldwide. Due to lack of gene expression signatures for risk and prognosis stratification of lung adenocarcinoma, identifying novel molecular biomarkers and therapeutic targets may potentially improve lung adenocarcinoma prognosis and treatment. In the current study, we investigate the role of USP53 in lung adenocarcinoma. Bioinformatics analysis, quantitative reverse transcription polymerase chain reaction, and Western blot were employed to examine patterns of gene expression in human lung adenocarcinoma database, patient samples, and cancer cell lines. Stable cell lines were produced by transducing with USP53 overexpression vector or short hairpin RNA targeting USP53 in the presence and absence of AKT pathway inhibitor LY294002. Functional assays were carried out to examine the impact of USP53 and AKT pathway on lung adenocarcinoma cell viability, apoptosis, and glycolysis in vitro, as well as tumor growth in vivo. The correlation between USP53 and FKBP51 was measured by coimmunoprecipitation and ubiquitination assay. Decreased USP53 levels are a reliable marker of lung adenocarcinoma across published datasets, clinical samples, and cell culture lines. Low USP53 expression is linked to decreased apoptosis and increased metabolic activity, suggesting it acts as a tumor suppressor. USP53 regulates cell apoptosis and glycolysis through the AKT1 pathway. Mechanistically, USP53 deubiquitinates FKBP51, which in turn dephosphorylates AKT1, and ultimately inhibits tumor growth in lung adenocarcinoma. Taken together, our study establishes USP53 as a novel regulator of AKT1 pathway with an important role in tumorigenesis in lung adenocarcinoma.

Non-Coding RNAs Operate in the Crosstalk Between Cancer Metabolic Reprogramming and Metastasis

Metastasis, the spread of cancer cells from a primary tumor to a secondary site, represents one of the hallmarks of malignancies and the leading cause of cancer-related death. The process of metastasis is a result of the interaction of genetic heterogeneity, abnormal metabolism, and tumor microenvironments. On the other hand, metabolic reprogramming, another malignancy hallmark, refers to the ability of cancer cells to alter metabolic and nutrient acquisition modes in order to support the energy demands for accomplishing the rapid growth, dissemination, and colonization. Cancer cells remodel metabolic patterns to supplement nutrients for their metastasis and also undergo metabolic adjustments at different stages of metastasis. Genes and signaling pathways involved in tumor metabolic reprogramming crosstalk with those participating in metastasis. Non-coding RNAs are a group of RNA molecules that do not code proteins but have pivotal biological functions. Some of microRNAs and lncRNAs, which are the two most extensively studied non-coding RNAs, have been identified to participate in regulating metabolic remodeling of glucose, lipid, glutamine, oxidative phosphorylation, and mitochondrial respiration, as well as the process of metastasis involving cell motility, transit in the circulation and growth at a new site. This article reviews recent progress on non-coding RNAs operating in the crosstalk between tumor metabolic reprogramming and metastasis, particularly those influencing metastasis through regulating metabolism, and the underlying mechanisms of how they exert their regulatory functions.

Crosstalk of MicroRNAs and Oxidative Stress in the Pathogenesis of Cancer

Oxidative stress refers to an imbalance between reactive oxygen species (ROS) generation and body's capability to detoxify the reactive mediators or to fix the relating damage. MicroRNAs are considered to be important mediators that play essential roles in the regulation of diverse aspects of carcinogenesis. Growing studies have demonstrated that the ROS can regulate microRNA biogenesis and expression mainly through modulating biogenesis course, transcription factors, and epigenetic changes. On the other hand, microRNAs may in turn modulate the redox signaling pathways, altering their integrity, stability, and functionality, thus contributing to the pathogenesis of multiple diseases. Both ROS and microRNAs have been identified to be important regulators and potential therapeutic targets in cancers. However, the information about the interplay between oxidative stress and microRNA regulation is still limited. The present review is aimed at summarizing the current understanding of molecular crosstalk between microRNAs and the generation of ROS in the pathogenesis of cancer.

The interplay between HIF-1α and noncoding RNAs in cancer

Hypoxia is a classic characteristic of the tumor microenvironment with a significant impact on cancer progression and therapeutic response. Hypoxia-inducible factor-1 alpha (HIF-1α), the most important transcriptional regulator in the response to hypoxia, has been demonstrated to significantly modulate hypoxic gene expression and signaling transduction networks. In past few decades, growing numbers of studies have revealed the importance of noncoding RNAs (ncRNAs) in hypoxic tumor regions. These hypoxia-responsive ncRNAs (HRNs) play pivotal roles in regulating hypoxic gene expression at the transcriptional, posttranscriptional, translational and posttranslational levels. In addition, as a significant gene expression regulator, ncRNAs exhibit promising roles in regulating HIF-1α expression at multiple levels. In this review, we briefly elucidate the reciprocal regulation between HIF-1α and ncRNAs, as well as their effect on cancer cell behaviors. We also try to summarize the complex feedback loop existing between these two components. Moreover, we evaluated the biomarker potential of HRNs for the diagnosis and prognosis of cancer, as well as the potential clinical utility of shared regulatory mechanisms between HIF-1α and ncRNAs in cancer treatment, providing novel insights into tumorigenicity, which may lead to innovative clinical applications.

Hypoxia‑inducible factors in hepatocellular carcinoma (Review)

Maintenance of an appropriate oxygen concentration is essential for the function of the liver. However, in many pathological conditions, and particularly in the tumor microenvironment, cells and tissues are frequently in a hypoxic state. In the presence of hypoxia, the cells adapt to the low oxygen levels through the hypoxia-inducible factor (HIF) pathway. Overgrowth of tumor cells restricts the diffusion of oxygen in tumors, leading to insufficient blood supply and the creation of a hypoxic microenvironment, and, as a consequence, activation of the expression of HIFs. HIFs possess a wide range of target genes, which function to control a variety of signaling pathways; thus, HIFs modulate cellular metabolism, immune escape, angiogenesis, metastasis, extracellular matrix remodeling, cancer stem cells and other properties of the tumor. Given their crucial role in the occurrence and development of tumors, HIFs are expected to become new targets of precise treatment of hepatocellular carcinoma.

MicroRNA-592 suppresses the malignant phenotypes of thyroid cancer by regulating lncRNA NEAT1 and downregulating NOVA1

Numerous studies have demonstrated that various microRNAs (miRs) are aberrantly expressed in thyroid cancer and play critical roles in thyroid cancer malignancy. The aberrant expression of miR‑592 has frequently been reported in multiple human cancer types; however, its expression profile and functions in thyroid cancer remain poorly understood. Reverse transcription‑quantitative polymerase chain reaction was carried out to determine the expression profile of miR‑592 in thyroid cancer tissues and cell lines. The regulatory effects of miR‑592 upregulation on thyroid cancer cell proliferation, migration, and invasion in vitro, and tumor growth in vivo were investigated using a CCK‑8 assay, migration and invasion assays, and a xenograft tumor model, respectively. Furthermore, the mechanisms underlying miR‑592‑mediated suppression of the aggressive phenotypes of thyroid cancer cells were explored in detail. The results indicated that miR‑592 was significantly downregulated in thyroid cancer samples, and its downregulation was associated with lymph node metastasis and tumor‑node‑metastasis stage. Patients with thyroid cancer and low miR‑592 expression exhibited shorter overall survival than patients with high miR‑592 expression. Overexpression of miR‑592 resulted in decreased cell proliferation, migration, and invasion in thyroid cancer. In addition, neuro‑oncological ventral antigen 1 (NOVA1) was identified as a novel target gene of miR‑592 in thyroid cancer cells. Furthermore, ectopic NOVA1 expression may effectively abolish the tumor‑suppressing effects of miR‑592 overexpression in thyroid cancer cells. Notably, the lncRNA NEAT1 was proposed to function as a sponge of miR‑592 in thyroid cancer cells, thereby regulating NOVA1 expression. Finally, resuming miR‑592 expression significantly impaired thyroid cancer tumor growth in vivo. The results indicated that the NEAT1/miR‑592/NOVA1 pathway may play regulatory roles in thyroid cancer malignancy in vitro and in vivo. Our findings may provide novel insight into the pathogenesis of thyroid cancer. Therefore, this pathway may be an effective target for treating patients with this disease.

Down-regulation of MicroRNA-592 in obesity contributes to hyperglycemia and insulin resistance

Background

Many studies have demonstrated that microRNAs, a class of small and non-coding RNA molecules, play an important role in the regulation of glucose and lipid homeostasis. In the present study, we sought to investigate the function of miR-592 in the development of obesity-associated metabolic disorders, including hyperglycemia andinsulin resistance.

Methods

The expression levels of miR-592 were measured in the liver of obese mice and humans by quantitative reverse transcription PCR. Loss- and gain-of function experiments were employed to explore the metabolic function of miR-592 using locked nucleic acids and adenovirus in lean and obese mice, respectively. The molecular target of miR-592 was determined by western blotting and luciferase reporter assays.

Findings

We found a significant decreased expression of miR-592 in the liver of obese mice and humans. Inhibition of miR-592 led to elevated blood glucose levels, enhanced gluconeogenesis and reduced insulin sensitivity in lean mice. In contrast, adenovirus-mediated overexpression of hepatic miR-592 improved metabolic disorders in obese mice. Mechanistically, we found that the transcription factor forkhead box O1 (FOXO1) is a direct target gene of miR-592 to mediate its metabolic functions. miR-592 was able to inhibit the mRNA and protein expression of FOXO1 by binding to its 3′-untranslated region.

Interpretations

Our findings demonstrate that obesity-associated down-regulation of miR-592 plays an important role in the progression of metabolic diseases. Restoration of hepatic miR-592 could improve glucose and lipid metabolism in obese mice.

Fund

This work is supported by the National Key Research and Development Program of China (No. 2016YFC1304805 to Dr. Chen), Natural Science Foundation of China (No. 81771574 to Dr. Wu), Shanghai Science Foundation (No. 18ZR1437800 to Dr. Li), Science and Technology Commission of Shanghai Municipality (Nos.18dz2304400 and 15,411,970,700 to Dr. Yang).

Oncogenic miR-663a is associated with cellular function and poor prognosis in renal cell carcinoma

BACKGROUND

MicroRNA(miRNA) plays a key regulatory role in various stages of tumorigenesis, including cell growth, cell cycle control, apoptosis avoidance, tissue invasion, and metastasis. Several microRNAs are involved in the development of renal cell carcinoma (RCC) and the malignant transformation process. However, the effects of miR-663a on RCC have rarely been reported.

METHODS

In the present study, the expression of miR-663a was examined in RCC using matched normal kidney tissues and four cell lines (786-O, Caki-1, ACHN and HK-2). MicroRNA mimics were transiently transfected into RCC cells and the effects of over expression on proliferation, migration, invasion, and apoptosis was observed. In addition, the relationship between miR-663a expression in 42 formalin-fixed paraffin-embedded (FFPE) clear cell renal carcinoma (ccRCC) samples and clinical pathological variables and overall survival was investigated. We evaluated the prognostic value of miR-663a expression in ccRCC by experimental results.

RESULTS

The results showed that the expression of miR-663a was up-regulated in RCC cells and tissues and miR-663a was associated with proliferation, migration, invasion, and apoptosis of RCC. Cox proportional hazard regression analysis showed that a high expression of miR-663a patients had a significantly shorter overall survival in univariate and multivariate analysis. Kaplan-Meier survival curves showed that a high expression of miR-663a patients had a significantly shorter overall survival.

CONCLUSIONS

These results indicate that miR-663a can be used as an independent marker for the poor prognosis of ccRCC, and may also play an important role as a tumor oncogene in the occurrence and development of RCC.

Immunometabolism: A novel perspective of liver cancer microenvironment and its influence on tumor progression

The initiation and progression of liver cancer, including hepatocellular carcinoma and intrahepatic cholangiocarcinoma, are dependent on its tumor microenvironment. Immune cells are key players in the liver cancer microenvironment and show complicated crosstalk with cancer cells. Emerging evidence has shown that the functions of immune cells are closely related to cell metabolism. However, the effects of metabolic changes of immune cells on liver cancer progression are largely undefined. In this review, we summarize the recent findings of immunometabolism and relate these findings to liver cancer progression. We also explore the translation of the understanding of immunometabolism for clinical use.

Estrogen signaling deregulation related with local immune response modulation in irritable bowel syndrome

The etiology and pathogenesis underlying irritable bowel syndrome (IBS), a common gastrointestinal disorder are still unclear. Cumulating data suggest dysregulation of inflammatory and immune response pathways and changes of epithelial barrier function. The role of estrogens albeit varied, in responses of immune system is well documented. The aim of this study was to investigate estrogen receptors engagment in IBS subtypes, i.e. constipation predominant (IBS-C) and diarrhea predominant (IBS-D). Furthermore, we analyzed whether estrogen signaling is accompanied by alteration in expression of pro- and anti-inflammatory cytokines and microRNAs that can regulate among others genes involved in immune responses. It was found that estrogen receptor α (ERα) and G protein-coupled estrogen receptor (GPER) expression is up-regulated in IBS while estrogen receptor β (ERβ) appears to be down-regulated at mRNA but up-regulated at the protein level. When gender and female age were included statistically significant overexpression of ERα in IBS-D women under the age of 50, while of GPER in IBS-D men was stated. In all studied IBS samples disturbances in expression of cytokines IL-6, IL-10 and TNF-α as well as miR-145, miR-148-5p and miR-592 were observed. This research reveals the association of estrogen receptors with IBS. Simultaneous alterations of studied immunomodulatory cytokines and microRNAs suggest that in IBS dysregulation of local immune response may involve estrogen-dependent way.

Down-regulation of miR-146b-5p by long noncoding RNA MALAT1 in hepatocellular carcinoma promotes cancer growth and metastasis

MicroRNAs play an important role in liver cancer genesis and progression. In this study, we identified down-regulation of miR-146b-5p associated with tumor growth, metastasis and poor survival in hepatocellular carcinoma (HCC) patients. miR-146b-5p could suppress proliferation, migration, and invasion and induced apoptosis in vitro and in vivo. Remarkably, TNF receptor associated factor 6 (TRAF6) was confirmed as a direct target of miR-146b-5p in HCC and miR-146b-5p exerted the tumor suppression roles through inhibiting the phosphorylation of Akt mediated by TRAF6. Furthermore, we identified long non-coding RNA MALAT1 as a molecular sponge of miR-146b-5p to down-regulate its expression in HCC. In general, our results indicate that miR-146b-5p inhibits tumor growth and metastasis of HCC by targeting TRAF6 mediated Akt phosphorylation.

AKT-mediated phosphorylation of ATG4B impairs mitochondrial activity and enhances the Warburg effect in hepatocellular carcinoma cells

Phosphorylation is a major type of post-translational modification, which can influence the cellular physiological function. ATG4B, a key macroautophagy/autophagy-related protein, has a potential effect on the survival of tumor cells. However, the role of ATG4B phosphorylation in cancers is still unknown. In this study, we identified a novel phosphorylation site at Ser34 of ATG4B induced by AKT in HCC cells. The phosphorylation of ATG4B at Ser34 had little effect on autophagic flux, but promoted the Warburg effect including the increase of L-lactate production and glucose consumption, and the decrease of oxygen consumption in HCC cells. The Ser34 phosphorylation of ATG4B also contributed to the impairment of mitochondrial activity including the inhibition of F₁Fo-ATP synthase activity and the elevation of mitochondrial ROS in HCC cells. Moreover, the phosphorylation of ATG4B at Ser34 enhanced its mitochondrial location and the subsequent colocalization with F₁Fo-ATP synthase in HCC cells. Furthermore, recombinant human ATG4B protein suppressed the activity of F₁Fo-ATP synthase in MgATP submitochondrial particles from patient-derived HCC tissues in vitro. In brief, our results demonstrate for the first time that the phosphorylation of ATG4B at Ser34 participates in the metabolic reprogramming of HCC cells via repressing mitochondrial function, which possibly results from the Ser34 phosphorylation-induced mitochondrial enrichment of ATG4B and the subsequent inhibition of F₁Fo-ATP synthase activity. Our findings reveal a noncanonical working pattern of ATG4B under pathological conditions, which may provide a scientific basis for developing novel strategies for HCC treatment by targeting ATG4B and its Ser34 phosphorylation.

Differentially expressed miRNAs in hepatocellular carcinoma cells under hypoxic conditions are associated with transcription and phosphorylation

Hypoxia is a critical aspect of tumor biology and has been associated with poor prognosis and resistance to traditional therapy. In the present study, differentially expressed genes and microRNAs (miRNAs/miRs) were screened for in the hepatocellular carcinoma (HCC) cell line Huh7 under hypoxic conditions. On the basis of microarray data, 11,508 mRNAs and 58 miRNAs exhibiting ≥1.5-fold change in expression under hypoxic conditions were identified. Gene Ontology (GO) and Kyoto Encyclopedia or Genes and Genomes pathway analysis revealed that the differentially expressed genes were primarily involved in cell cycle regulation, cell division, transcription and G-protein-coupled receptor signaling pathways. Using the TargetScan and miRanda software packages with the miRNA-mRNA negative expression network, differentially expressed miRNA targets were predicted. GO analysis revealed that the primary function of these miRNAs was to regulate transcription and phosphorylation. The miRNA-mRNA networks for transcription and phosphorylation were analyzed. Network analysis revealed that the key miRNAs in these networks were miR-19a, miR-34a, miR-29a, mir-196a, miR-25 and miR-1207, whose potential gene targets include DNA-binding proteins, zinc-finger proteins and transcription factors. Certain protein kinases, includingmitogen-activated protein kinase (MAPK) 1, MAPK kinase kinase4 and cyclin-dependent kinase 18, were also revealed to be present in the network. In hypoxic HCC tissue, levels of several key miRNAs implicated in the network analyses (miR-19a, miR-34a, miR-25 and miR-1207) were revealed to exhibit increased expression levels compared with the surrounding tissue. The results of the present study provide evidence that miRNAs serve an important function in transcription and phosphorylation in the hypoxic response of HCC cells.

The Glycolytic Switch in Tumors: How Many Players Are Involved?

Reprogramming of cellular metabolism is a hallmark of cancers. Cancer cells more readily use glycolysis, an inefficient metabolic pathway for energy metabolism, even when sufficient oxygen is available. This reliance on aerobic glycolysis is called the Warburg effect, and promotes tumorigenesis and malignancy progression. The mechanisms of the glycolytic shift in tumors are not fully understood. Growing evidence demonstrates that many signal molecules, including oncogenes and tumor suppressors, are involved in the process, but how oncogenic signals attenuate mitochondrial function and promote the switch to glycolysis remains unclear. Here, we summarize the current information on several main mediators and discuss their possible mechanisms for triggering the Warburg effect.

Prognostic value of microRNAs in hepatocellular carcinoma: a meta-analysis

Background

Numerous articles reported that dysregulated expression levels of miRNAs correlated with survival time of HCC patients. However, there has not been a comprehensive meta-analysis to evaluate the accurate prognostic value of miRNAs in HCC.

Design

Meta-analysis.

Materials and Methods

Studies, published in English, estimating expression levels of miRNAs with any survival curves in HCC were identified up until 15 April, 2017 by performing online searches in PubMed, EMBASE, Web of Science and Cochrane Database of Systematic Reviews by two independent authors. The pooled hazard ratios (HR) with 95% confidence intervals (CI) were used to estimate the correlation between miRNA expression and overall survival (OS).

Results

54 relevant articles about 16 miRNAs, with 6464 patients, were ultimately included. HCC patients with high expression of tissue miR-9 (HR = 2.35, 95% CI = 1.46–3.76), miR-21 (HR = 1.76, 95% CI = 1.29–2.41), miR-34c (HR = 1.64, 95% CI = 1.05–2.57), miR-155 (HR = 2.84, 95% CI = 1.46–5.51), miR-221 (HR = 1.76, 95% CI = 1.02–3.04) or low expression of tissue miR-22 (HR = 2.29, 95% CI = 1.63–3.21), miR-29c (HR = 1.35, 95% CI = 1.10–1.65), miR-34a (HR = 1.84, 95% CI = 1.30–2.59), miR-199a (HR = 2.78, 95% CI = 1.89–4.08), miR-200a (HR = 2.64, 95% CI = 1.86–3.77), miR-203 (HR = 2.20, 95% CI = 1.61–3.00) have significantly poor OS (P < 0.05). Likewise, HCC patients with high expression of blood miR-21 (HR = 1.73, 95% CI = 1.07–2.80), miR-192 (HR = 2.42, 95% CI = 1.15–5.10), miR-224 (HR = 1.56, 95% CI = 1.14–2.12) or low expression of blood miR-148a (HR = 2.26, 95% CI = 1.11–4.59) have significantly short OS (P < 0.05).

Conclusions

In conclusion, tissue miR-9, miR-21, miR-22, miR-29c, miR-34a, miR-34c, miR-155, miR-199a, miR-200a, miR-203, miR-221 and blood miR-21, miR-148a, miR-192, miR-224 demonstrate significantly prognostic value. Among them, tissue miR-9, miR-22, miR-155, miR-199a, miR-200a, miR-203 and blood miR-148a, miR-192 are potential prognostic candidates for predicting OS in HCC.

miR-181d and c-myc-mediated inhibition of CRY2 and FBXL3 reprograms metabolism in colorectal cancer

Colorectal cancer (CRC) is the second major cause of tumor-related deaths. MicroRNAs (miRNAs) have pivotal roles in CRC progression. Here, we describe the effect of miR-181d on CRC cell metabolism and underlying molecular mechanism. Our data firmly demonstrated that knockdown of miR-181d suppressed CRC cell proliferation, migration, and invasion by impairing glycolysis. Mechanistically, miR-181d stabilized c-myc through directly targeting the 3'-UTRs of CRY2 and FBXL3, which subsequently increased the glucose consumption and the lactate production. Inhibition of c-myc via siRNA or small molecular inhibitor abolished the oncogenic effects of miR-181d on the growth and metastasis of CRC cells. Furthermore, c-myc/HDAC3 transcriptional suppressor complex was found to co-localize on the CRY2 and FBXL3 promoters, epigenetically inhibit their transcription, and finally induce their downregulation in CRC cells. In addition, miR-181d expression could be directly induced by an activation of c-myc signaling. Together, our data indicate an oncogenic role of miR-181d in CRC by promoting glycolysis, and miR-181d/CRY2/FBXL3/c-myc feedback loop might be a therapeutic target for patients with CRC.

MiR-592 functions as a tumor suppressor in glioma by targeting IGFBP2

A growing body of evidence suggests that microRNA-592 is involved in tumor initiation and development in several types of human cancers. However, the biological functions and molecular mechanism of microRNA-592 in glioma remain unclear. In this study, we explored the potential role of microRNA-592 in glioma as well as the possible molecular mechanisms. Our results proved that microRNA-592 expression was significantly downregulated in glioma tissues and cell lines (p < 0.01). Functional assays revealed that overexpression of microRNA-592 dramatically reduced the cell proliferation, migration, and invasion and induced cell arrest at G1/G0 phase in vitro. Mechanistic investigations defined insulin-like growth factor binding protein 2 as a direct and functional downstream target of microRNA-592, which was involved in the microRNA-592-mediated tumor-suppressive effects in glioma cells. Moreover, the in vivo study showed that microRNA-592 overexpression produced the smaller tumor volume and weight in nude mice. In summary, these results elucidated the function of microRNA-592 in glioma progression and suggested a promising application of it in glioma treatment.

MicroRNA-124 suppresses proliferation and glycolysis in non-small cell lung cancer cells by targeting AKT-GLUT1/HKII

Non-small cell lung cancer accounts for 85% of all types of lung cancer and is the leading cause of worldwide cancer-associated mortalities. MiR-124 is epigenetically silenced in various types of cancer and plays important roles in tumor development and progression. MiR-124 was also significantly downregulated in non-small cell lung cancer patients. Glycolysis has been considered as a feature of cancer cells; hypoxia-inducible factor 1-alpha/beta and Akt are key enzymes in the regulation of glycolysis and energy metabolism in cancer cells. However, the role of miR-124 in non-small cell lung cancer cell proliferation, glycolysis, and energy metabolism remains unknown. In this research, cell proliferation was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; furthermore, glucose consumption and lactic acid production were assessed; adenosine triphosphate content and NAD⁺/NADH were also detected. These tests were conducted using the normal non-small cell lung cancer cell line A549, which was transfected variedly with miR-mimics, miR-124 mimics, miR-124 inhibitor, pc-DNA3.1(+)-AKT1, and pc-DNA3.1(+)-AKT2 plasmid. Here, we show that miR-124 overexpression directly decreased cell growth, glucose consumption, lactate production, and energy metabolism. MiR-124 also negatively regulates glycolysis rate-limiting enzymes, glucose transporter 1 and hexokinase II. Our results also showed that miR-124 negatively regulates AKT1 and AKT2 but no regulatory effect on hypoxia-inducible factor 1-alpha/beta. Overexpression of AKT reverses the inhibitory effect of miR-124 on cell proliferation and glycolytic metabolism in non-small cell lung cancer. AKT inhibition blocks miR-124 silencing-induced AKT1/2, glucose transporter 1, hexokinase II activation, cell proliferation, and glycolytic or energy metabolism changes. In summary, this study demonstrated that miR-124 is able to inhibit proliferation, glycolysis, and energy metabolism, potentially by targeting AKT1/2-glucose transporter 1/hexokinase II in non-small cell lung cancer cells.

Advances in Hypoxia-Mediated Mechanisms in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common and the third most deadly malignant tumor worldwide. Hypoxia and related oxidative stress are heavily involved in the process of HCC development and its therapies. However, direct and accurate measurement of oxygen concentration and evaluation of hypoxic effects in HCC prove difficult. Moreover, the hypoxia-mediated mechanisms in HCC remain elusive. Here, we summarize recent major evidence of hypoxia in HCC lesions shown by measuring partial pressure of oxygen (pO₂), the clinical importance of hypoxic markers in HCC, and recent advances in hypoxia-related mechanisms and therapies in HCC. For the mechanisms, we focus mainly on the roles of oxygen-sensing proteins (i.e., hypoxia-inducible factor and neuroglobin) and hypoxia-induced signaling proteins (e.g., matrix metalloproteinases, high mobility group box 1, Beclin 1, glucose metabolism enzymes, and vascular endothelial growth factor). With respect to therapies, we discuss mainly YQ23, sorafenib, 2-methoxyestradiol, and celastrol. This review focuses primarily on the results of clinical and animal studies.

WSB1: from homeostasis to hypoxia

The wsb1 gene has been identified to be important in developmental biology and cancer. A complex transcriptional regulation of wsb1 yields at least three functional transcripts. The major expressed isoform, WSB1 protein, is a substrate recognition protein within an E3 ubiquitin ligase, with the capability to bind diverse targets and mediate ubiquitinylation and proteolytic degradation. Recent data suggests a new role for WSB1 as a component of a neuroprotective pathway which results in modification and aggregation of neurotoxic proteins such as LRRK2 in Parkinson’s Disease, via an unusual mode of protein ubiquitinylation.

WSB1 is also involved in thyroid hormone homeostasis, immune regulation and cellular metabolism, particularly glucose metabolism and hypoxia. In hypoxia, wsb1 is a HIF-1 target, and is a regulator of the degradation of diverse proteins associated with the cellular response to hypoxia, including HIPK2, RhoGDI2 and VHL. Major roles are to both protect HIF-1 function through degradation of VHL, and decrease apoptosis through degradation of HIPK2. These activities suggest a role for wsb1 in cancer cell proliferation and metastasis. As well, recent work has identified a role for WSB1 in glucose metabolism, and perhaps in mediating the Warburg effect in cancer cells by maintaining the function of HIF1. Furthermore, studies of cancer specimens have identified dysregulation of wsb1 associated with several types of cancer, suggesting a biologically relevant role in cancer development and/or progression.

Recent development of an inducible expression system for wsb1 could aid in the further understanding of the varied functions of this protein in the cell, and roles as a potential oncogene and neuroprotective protein.