MiR-30a-5p Inhibits Epithelial-to-Mesenchymal Transition and Upregulates Expression of Tight Junction Protein Claudin-5 in Human Upper Tract Urothelial Carcinoma Cells

miR-194-3p regulates epithelial-mesenchymal transition in embryonic epicardial cells via p120/β-catenin signaling

The epicardium is integral to cardiac development and facilitates endogenous heart regeneration and repair. While miR-194-3p is associated with cellular migration and invasion, its impact on epicardial cells remains uncharted. In this work we use gain-of-function and loss-of-function methodologies to investigate the function of miR-194-3p in cardiac development. We culture embryonic epicardial cells in vitro and subject them to transforming growth factor β (TGF-β) treatment to induce epithelial-mesenchymal transition (EMT) and monitor miR-194-3p expression. In addition, the effects of miR-194-3p mimics and inhibitors on epicardial cell development and changes in EMT are investigated. To validate the binding targets of miR-194-3p and its ability to recover the target gene-phenotype, we produce a mutant vector p120-catenin-3'UTR-MUT. In epicardial cells, TGF-β-induced EMT results in a notable overexpression of miR-194-3p. The administration of miR-194-3p mimics promotes EMT, which is correlated with elevated levels of mesenchymal markers. Conversely, miR-194-3p inhibitor attenuates EMT. Further investigations reveal a negative correlation between miR-194-3p and p120-catenin, which influences β-catenin level in the cell adhesion pathway. The suppression of EMT caused by the miR-194-3p inhibitor is balanced by silencing of p120-catenin. In conclusion, miR-194-3p directly targets p120-catenin and modulates its expression, which in turn alters β-catenin expression, critically influencing the EMT process in the embryonic epicardial cells via the cell adhesion mechanism.

MicroRNA-26a-5p Restoration Ameliorates Unilateral Ureteral Obstruction-Induced Renal Fibrosis In Mice Through Modulating TGF-β Signaling

Renal fibrosis is a hallmark of chronic and progressive renal diseases characterized by excessive fibroblast proliferation, extracellular matrix accumulation, and loss of renal function, eventually leading to end-stage renal diseases. MicroRNA-26a-5p downregulation has been previously noted in the sera of unilateral ureteral occlusion (UUO)-injured mice, and exosome-mediated miR-26a-5p reportedly attenuated experimental pulmonary and cardiac fibrosis. This study evaluated the expression patterns of miR-26a in human tissue microarray with kidney fibrosis and in tissues from a mouse model of UUO-induced renal fibrosis. Histological analyses showed that miR-26a-5p was downregulated in human and mouse tissues with renal interstitial nephritis and fibrosis. Moreover, miR-26a-5p restoration by intravenous injection of a mimic agent prominently suppressed the expression of TGF-β1 and its cognate receptors, the inflammatory transcription factor NF-κB, epithelial-mesenchymal transition, and inflammatory markers in UUO-injured kidney tissues. In vitro miR-26a-5p mimic delivery significantly inhibited TGF-β1-induced activation of cultured rat kidney NRK-49F cells, in terms of downregulation of TGF-β1 receptors, restoration of epithelial marker E-cadherin, and suppression of mesenchymal markers, including vimentin, fibronectin, and α-smooth muscle actin, as well as TGF-β1/SMAD3 signaling activity. Our findings identified miR-26a-5p downregulation in kidney tissues from human interstitial nephritis and UUO-induced mouse kidney fibrosis. MiR-26a-5p restoration may exhibit an anti-fibrotic effect through the blockade of both TGF-β and NF-κB signaling axes and is considered a novel therapeutic target for treating obstruction-induced renal fibrosis.

Genetic Interference of FGFR3 Impedes Invasion of Upper Tract Urothelial Carcinoma Cells by Alleviating RAS/MAPK Signal Activity

Upper tract urothelial cancer (UTUC) is a less common disease in Western countries but has a high level of prevalence in Asian populations. Compared to bladder cancer, unique etiologic and genomic factors are involved in UTUC. Fibroblast growth factor receptor 3 (FGFR3) up-regulation has been proposed as a promising target for bladder cancer therapy. In this study, we aimed to profile the expression of FGFR3 in Asian and Caucasian UTUC tissues and to evaluate the in vitro therapeutic efficacy of small interference RNA (siRNA)-mediated FGFR3 silencing in UTUC treatment. The FGFR3 expression levels in renal pelvis tissues and microarray sections from Asian and Caucasian patients with UTUC, respectively, were measured via immunohistochemistry. The BFTC-909 and UM-UC-14 UTUC cell lines were used to examine the effects of FGFR3 silencing on proliferation, migration, epithelial-mesenchymal transition (EMT) marker expression, and signaling machinery. FGFR3 expression increased as the TNM stage increased in both Asian and Caucasian UTUC tumors, and no statistical difference was identified between the two groups. In vitro studies demonstrated that FGFR3 siRNA delivery significantly inhibited proliferation and migration and suppressed the expression of EMT markers and transcription factors in UTUC cells. Mechanistically, FGFR3 silencing alleviated the constitutive expression of RAS and the phosphorylation of MAPK signaling mediators, including ERK1/2 and JNK1/2. FGFR3 silencing elicited an apoptosis-inducing effect similar to that of FGFR inhibition. Conclusion: siRNA-targeted FGFR3 expression may impede the expansion and invasion of UTUC cells by alleviating the RAS/MAPK signaling pathway. The genetic interference of FGFR3 expression via siRNA in UTUC cells may constitute a useful therapeutic strategy.

Epigenetically-regulated miR-30a/c-5p directly target TWF1 and hamper ccRCC cell aggressiveness

Clear cell renal cell carcinoma (ccRCC) is highly prone to metastasize and displays an extremely low 5-year survival rate. Not only miRNAs (miRs) are key gene expression regulators but can also be epigenetically modified. Abnormal miR expression has been linked with epithelial-mesenchymal transition (EMT)-driven ccRCC progression. MiR-30a/c-5p were found downregulated in ccRCC and associated with aggressiveness. Herein, we sought to unravel miR-30a/c-5p mechanistic role in ccRCC. RNA sequencing and genome-wide methylome data of ccRCC and normal tissue samples from The Cancer Genome Atlas database were integrated to identify candidate miRs cytosine-phosphate-guanine (CpG) loci deregulated in ccRCC. TargetScan was searched to identify miR putative targets. MiR-30a/c-5p expression and promoter methylation was evaluated in vitro, by PCR. Western blot, functional and luciferase assays were performed after cell transfection with either pre-miR, antimiR, or siRNA against twinfilin-1 (TWF1). Immunohistochemistry (IHC) was performed in ccRCC tissues. We found miR-30c-5p downregulation and aberrant promoter methylation in ccRCC tissues. In vitro studies revealed concomitant miR-30a/c-5p downregulation and increased promoter methylation, as well as a significant re-expression following decitabine treatment. Functional assays demonstrated that both miRs significantly decreased cell aggressiveness and the protein levels of EMT-promoting players, while upregulating epithelial markers, namely Claudin-1 and ZO-1. Importantly, we confirmed TWF1 as a direct target of both miRs, and its potential involvement in epithelial-mesenchymal transition/mesenchymal-epithelial transition regulation. IHC analysis revealed higher TWF1 expression in primary tissues from patients that developed metastases, after surgical treatment. Our results implicate miR-30a/c-5p in ccRCC cells' aggressiveness attenuation by directly targeting TWF1 and hampering EMT.

MiR-26a-5p as a useful therapeutic target for upper tract urothelial carcinoma by regulating WNT5A/β-catenin signaling

The role of miRNAs in cancer and their possible function as therapeutic agents are interesting and needed further investigation. The miR-26a-5p had been demonstrated as a tumor suppressor in various cancers. However, the importance of miR-26a-5p regulation in upper tract urothelial carcinoma (UTUC) remains unclear. Here, we aimed to explore the miR-26a-5p expression in UTUC tissues and to identify its regulatory targets and signal network involved in UTUC tumorigenesis. The miR-26a-5p expression was validated by quantitative real-time polymerase chain reaction (qPCR) using renal pelvis tissue samples from 22 patients who were diagnosed with UTUC and 64 cases of renal pelvis tissue microarray using in situ hybridization staining. BFTC-909 UTUC cells were used to examine the effects of miR-26a-5p genetic delivery on proliferation, migration and expression of epithelial-to-mesenchymal transition (EMT) markers. MiR-26a-5p was significantly down-regulated in UTUC tumors compared to adjacent normal tissue and was decreased with histological grades. Moreover, restoration of miR-26a-5p showed inhibition effects on proliferation and migration of BFTC-909 cells. In addition, miR-26a-5p delivery regulated the EMT marker expression and inhibited WNT5A/β-catenin signaling and expression of downstream molecules including NF-κB and MMP-9 in BFTC-909 cells. This study demonstrated that miR-26a-5p restoration may reverse EMT process and regulate WNT5A/β-catenin signaling in UTUC cells. Further studies warranted to explore the potential roles in biomarkers for diagnostics and prognosis, as well as novel therapeutics targets for UTUC treatment.

MicroRNA Signatures in the Upper Urinary Tract Urothelial Carcinoma Scenario: Ready for the Game Changer?

Upper urinary tract urothelial carcinoma (UTUC) represents a minor subgroup of malignancies arising in the urothelium of the renal pelvis or ureter. The estimated annual incidence is around 2 cases per 100,000 people, with a mean age at diagnosis of 73 years. UTUC is more frequently diagnosed in an invasive or metastatic stage. However, even though the incidence of UTUC is not high, UTUC tends to be aggressive and rapidly progressing with a poor prognosis in some patients. A significant challenge in UTUC is ensuring accurate and timely diagnosis, which is complicated by the non-specific nature of symptoms seen at the onset of disease. Moreover, there is a lack of biomarkers capable of identifying the early presence of the malignancy and guide-tailored medical treatment. However, the growing understanding of the molecular biology underlying UTUC has led to the discovery of promising new biomarkers. Among these biomarkers, there is a class of small non-coding RNA biomarkers known as microRNAs (miRNAs) that are particularly promising. In this review, we will analyze the main characteristics of UTUC and focus on microRNAs as possible novel tools that could enter clinical practice in order to optimize the current diagnostic and prognostic algorithm.

MicroRNAs and Heat Shock Proteins in Breast Cancer Biology

Breast cancer has five major immune types; luminal A, luminal B, HER2, Basal-like, and normal-like. Cells produce a family of protein called heat shock proteins (Hsps) in response to exposure to thermal and other proteotoxic stresses play essential roles in cancer metabolism and this large family shows a diverse set of Hsp involvement in different breast cancer immune types. Recently, Hsp members categorized according to their immune type roles. Hsp family consists of several subtypes formed by molecular weight; Hsp70, Hsp90, Hsp100, Hsp40, Hsp60, and small molecule Hsps. Cancer cells employ Hsps as survival factors since most of these proteins prevent apoptosis. Several studies monitored Hsp roles in breast cancer cells and reported Hsp27 involvement in drug resistance, Hsp70 in tumor cell transformation-progression, and interaction with p53. Furthermore, the association of Hsp90 with steroid receptors and signaling proteins in patients with breast cancer directed research to focus on Hsp-based treatments. miRNAs are known to play key roles in all types of cancer that are upregulated or downregulated in cancer which respectively referred to as oncogenes (oncomirs) or tumor suppressors. Expression profiles of miRNAs may be used to classify, diagnose, and predict different cancer types. It is clear that miRNAs play regulatory roles in gene expression and this work reveals miRNA correlation to Hsp depending on specific breast cancer immune types. Deregulation of specific Hsp genes in breast cancer subtypes allows for identification of new targets for drug design and cancer treatment. Here, we performed miRNA network analysis by recruiting Hsp genes detected in breast cancer subtypes and reviewed some of the miRNAs related to aforementioned Hsp genes.

Research Progress on the Role of Intermediate Filament Vimentin in Atherosclerosis

The cytoskeleton is a biopolymer network composed of intermediate filaments, actin, and microtubules, which is the main mechanical structure of cells. Vimentin is an intermediate filament protein that regulates the mechanical and contractile properties of cells, thereby reflecting their mechanical properties. In recent years, the "nonmechanical function" of vimentin inside and outside of cells has attracted extensive attention. The content of vimentin in atherosclerotic plaques is increased, and the serum secretion of vimentin in patients with coronary heart disease is remarkably increased. In this review, the mechanistic and nonmechanistic roles of vimentin in atherosclerosis progression were summarized on the basis of current studies.

MicroRNA as a Biomarker for Diagnostic, Prognostic, and Therapeutic Purpose in Urinary Tract Cancer

The incidence of urologic cancers, including kidney, upper tract urothelial, and bladder malignancies, is increasing globally, with a high percentage of cases showing metastasis upon diagnosis and low five-year survival rates. MicroRNA (miRNA), a small non-coding RNA, was found to regulate the expression of oncogenes and tumor suppressor genes in several tumors, including cancers of the urinary system. In the current review, we comprehensively discuss the recently reported up-or down-regulated miRNAs as well as their possible targets and regulated pathways involved in the development, progression, and metastasis of urinary tract cancers. These miRNAs represent potential therapeutic targets and diagnostic/prognostic biomarkers that may help in efficient and early diagnosis in addition to better treatment outcomes.

The MicroRNA Prediction Models as Ancillary Diagnosis Biomarkers for Urothelial Carcinoma in Patients With Chronic Kidney Disease

Urothelial carcinoma is a common urological cancer in chronic kidney disease patients. Cystoscopy and urine cytology are the clinical diagnostic tools for UC. However, cystoscopy is an invasive procedure, while urine cytology showed low sensitivity for low-grade urothelial tumors. High accuracy with non-invasive tools for UC is needed for CKD patients. Our study collected a total of 272 urine and 138 plasma samples to detect the miRNA expression levels for establishing UC signatures from CKD patients. Seventeen candidate miRNAs of biofluids were selected and confirmed by qRT-PCR. Our results showed that urinary miR-1274a and miR-30a-5p expression levels were significantly lower but miR-19a-5p expression levels were higher in UC when compared with CKD. In plasma samples, miR-155-5p, miR-19b-1-5p, miR-378, and miR-636 showed significantly lower expression in UC compared to those with CKD. The Kaplan-Meier curve showed that lower expression of miR-19a, miR-19b, miR-636 and miR-378, and higher expression of miR-708-5p were associated with poor prognosis in patients with bladder cancer. In addition, we produced classifiers for predicting UC by multiple logistic regression. The urine signature was developed with four miRNAs, and the AUC was 0.8211. Eight miRNA expression levels from both urine and plasma samples were examined, and the AUC was 0.8595. Two miRNA classifiers and the nomograms could improve the drawbacks of current UC biomarker screenings for patients with CKD.

Noncoding RNAs Associated with Therapeutic Resistance in Pancreatic Cancer

Therapeutic resistance is an inevitable impediment towards effective cancer therapies. Evidence accumulated has shown that the signaling pathways and related factors are fundamentally responsible for therapeutic resistance via regulating diverse cellular events, such as epithelial-to-mesenchymal transition (EMT), stemness, cell survival/apoptosis, autophagy, etcetera. Noncoding RNAs (ncRNAs) have been identified as essential cellular components in gene regulation. The expression of ncRNAs is altered in cancer, and dysregulated ncRNAs participate in gene regulatory networks in pathological contexts. An in-depth understanding of molecular mechanisms underlying the modulation of therapeutic resistance is required to refine therapeutic benefits. This review presents an overview of the recent evidence concerning the role of human ncRNAs in therapeutic resistance, together with the feasibility of ncRNAs as therapeutic targets in pancreatic cancer.

Involvement of miR-30a-5p and miR-30d in Endothelial to Mesenchymal Transition and Early Osteogenic Commitment under Inflammatory Stress in HUVEC

The endothelial to mesenchymal transition (End–MT) can be associated with vascular calcification, by providing mesengenic progenitors. In this study, we investigated a link between End–MT and the osteogenic process and explored the involvement of miR-30a-5p and miR-30d as potential regulators of these processes. End–MT was induced in Human Umbilical Vein Endothelial Cells (HUVEC) through transforming growth factor-β1 (TGF-β1), TGFβ-3 and tumor necrosis factor-α (TNF-α), for 24 h and 6 days. End–MT mediators, mesenchymal and osteo/chondrogenic markers were analyzed through Real-Time PCR, immunofluorescence, flow cytometry and Western Blot. miR-30a-5p and miR-30d over-expression was carried out in HUVEC to explore their effects on End–MT and osteogenic differentiation. HUVEC at 24 h and 6 days gained mesenchymal morphology markers, including matrix metalloproteinase 9 (MMP-9), SLUG, VIMENTIN and α-smooth muscle actin (α-SMA), and a significant migratory potential, notably with TNF-α. After 6 days, the osteo/chondrogenic markers runt-related transcription factor 2 (RUNX-2) and SRY box transcription factor 9 (SOX-9) were upregulated. At this time point, miR-30a-5p and miR-30d decreased. Over-expression of miR-30a-5p and miR-30d affected End–MT mediators and the osteogenic potency in HUVEC, by reducing SLUG, VIMENTIN and RUNX-2. Our data suggest that End–MT represents a key link between inflammation and vascular calcification. Further, miR-30a-5p and miR-30d can regulate both the End–MT and the osteogenic processes, prompting future studies for exploring their potential use as therapeutic targets or biomarkers in vascular diseases.

MicroRNAs and target molecules in bladder cancer

Bladder cancer (BC) is considered as one of the most common malignant tumors in humans with complex pathogenesis including gene expression variation, protein degradation, and changes in signaling pathways. Many studies on involved miRNAs in BC have demonstrated that they could be used as potential biomarkers in the prognosis, response to treatment, and screening before the cancerous phenotype onset. MicroRNAs (miRNAs) regulate many cellular processes through their different effects on special targets along with modifying signaling pathways, apoptosis, cell growth, and differentiation. The diverse expression of miRNAs in cancerous tissues could mediate procedures leading to the oncogenic or suppressor behavior of certain genes in cancer cells. Since a specific miRNA may have multiple targets, an mRNA could also be regulated by multiple miRNAs which further demonstrates the actual role of miRNAs in cancer. In addition, miRNAs can be utilized as biomarkers in some cancers that cannot be screened in the early stages. Hence, finding blood, urine, or tissue miRNA biomarkers by novel or routine gene expression method could be an essential step in the prognosis and control of cancer. In the present review, we have thoroughly evaluated the recent findings on different miRNAs in BC which can provide comprehensive information on better understanding the role of diverse miRNAs and better decision making regarding the new approaches in the diagnosis, prognosis, prevention, and treatment of BC.

Molecular Characterization of Upper Tract Urothelial Carcinoma in the Era of Next-generation Sequencing: A Systematic Review of the Current Literature

CONTEXT

While upper tract urothelial carcinoma (UTUC) share histological appearance with bladder cancer (BC), the former has differences in etiology and clinical phenotype consistent with characteristic molecular alterations.

OBJECTIVE

To systematically evaluate current genomic sequencing and proteomic data examining molecular alterations in UTUC.

EVIDENCE ACQUISITION

A systematic review using PubMed, Scopus, and Web of Science was performed in December 2019 according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement.

EVIDENCE SYNTHESIS

A total of 46 publications were selected for inclusion in this report, including 13 studies assessing genome-wide alterations, 18 studies assessing gene expression or microRNA expression profiles, three studies assessing proteomics, one study assessing genome-wide DNA methylation, and 14 studies evaluating distinct pathway alteration patterns. Differences between sporadic and hereditary UTUC, and between UTUC and BC, as well as molecular profiles associated with exposure to aristolochic acid are highlighted. Molecular pathways relevant to UTUC biology, such as alterations in FGFR3, TP53, or microsatellite instability, are discussed. Our findings are limited by tumor and patient heterogeneity and different platforms used in the studies.

CONCLUSIONS

Molecular events in UTUC and BC can be shared or distinct. Consequently, molecular subtypes differ according to location. Further work is needed to define the epigenomic and proteomic features of UTUC, and understand the mechanisms by which they shape the clinical behavior of UTUC.

PATIENT SUMMARY

We report the current data on the molecular alterations specific to upper tract urothelial carcinoma (UTUC), resulting from novel genomic and proteomic technologies. Although UTUC biology is comparable with that of bladder cancer, the rates and UTUC-enriched alterations support its uniqueness and the need for precision medicine strategies for this rare tumor type.

miR-331 inhibits CLDN2 expression and may alleviate the vascular endothelial injury induced by sepsis

The present study aimed to determine the expression level of claudin-2 (CLDN2) in the peripheral blood of patients with sepsis, and to investigate its potential function and mechanism of action in vascular endothelial injury. A total of 25 patients with sepsis were included in the present study. Reverse transcription-quantitative PCR was used to determine CLDN2 levels in peripheral blood. HUVECs stably expressing CLDN2 were prepared and Cell Counting Kit-8, flow cytometry and Transwell assays were performed to study the proliferation, apoptosis and migration of HUVECs, respectively. Using bioinformatics, microRNA (miR) molecules that interact with CLDN2 were predicted. A dual luciferase reporter assay was used to test whether miR-331 regulated CLDN2. Western blotting was employed to determine CLDN2 protein expression. In addition, in vitro transfection of HUVECs with miR-331 mimics was performed to test the rescue effects of miR-331 on the cell function changes induced by CLDN2. The results indicated that elevated CLDN2 expression altered the proliferation and cell cycle of peripheral vascular endothelial cells. CLDN2 overexpression inhibited HUVEC proliferation via mechanisms not associated with the cell cycle. CLDN2 mRNA levels in the peripheral blood of patients with sepsis were significantly higher than those in healthy subjects. Upregulated CLDN2 expression promoted the apoptosis of HUVECs, but reduced their proliferation and migration. Notably, miR-331 was able to bind with CLDN2 mRNA and regulate its expression. Upregulation of miR-331 expression inhibited the expression of CLDN2 and restored nearly normal proliferation, apoptosis and migration to HUVECs. The present study demonstrated that CLDN2 expression is elevated in peripheral blood from patients with sepsis, and promotes the injury of vascular endothelial cells. In addition, miR-331 participates in the direct regulation of CLDN2, and upregulation of miR-331 expression inhibits the expression of CLDN2 and restores cellular functions to HUVECs.

Plasma miR-30a-5p as an early novel noninvasive diagnostic and prognostic biomarker for lung cancer

Aim: Circulation miRNAs have become increasingly appreciated in the diagnosis and prognosis of lung cancer. This study aims to identify and evaluate plasma miRNA-30a-5p as an early noninvasive biomarker for the diagnosis and prognosis of lung cancer. Pateints & methods: Expression levels of plasma miRNA 30a-5p were measured by quantitative real-time PCR. Receiver operating characteristic analysis and area under the curve were used to differentiate malignant from benign tumors and from healthy controls. Kaplan-Meier curves and Cox regression were used to determine survival and prognosis. Results: Our results suggest that the level of miRNA-30a-5p in plasma might be a considerable early novel noninvasive diagnostic and prognostic biomarker for lung cancer. Conclusion: Prospective studies must be performed to confirm this new early novel noninvasive diagnostic and prognostic biomarker for lung cancer.

Role of HIF-1α-miR30a-Snai1 Axis in Neonatal Hyperoxic Lung Injury

Bronchopulmonary dysplasia (BPD) is characterized by a severe impairment in lung alveolarization and vascular development. We have previously shown that pulmonary angiogenesis is preserved in hyperoxia-exposed female mice accompanied by increased miR-30a expression, which is a proangiogenic miRNA. Also, miR-30a expression is decreased in human BPD. HIF-1α plays an essential role in postnatal lung development, especially in recovery from hyperoxic injury. Snai1 activation promotes pathological fibrosis through many mechanisms including Endo-MT, which may in turn adversely impact lung vascular development. Our objective was to test the hypothesis that higher miR-30a expression through HIF-1α decreases Snai1 expression in females and attenuates injury in the developing lung. Neonatal male and female mice (C57BL/6) were exposed to hyperoxia (P1-5, 0.95 FiO₂) and euthanized on P21. Neonatal human pulmonary microvascular endothelial cells (HPMECs; 18-24-week gestation donors; 3/group either sex) were subjected to hyperoxia (95% O₂ and 5% CO₂) or normoxia (air and 5% CO₂) up to 72 h. Snai1 expression was measured in HPMECs in vitro and in neonatal mouse lungs in vivo. Also, Snai1 expression was measured in HPMECs after miR-30a mimic and miR-30a inhibitor treatment. To further establish the potential regulation of miR-30a by Hif-1α, miR-30a expression after Hif-1α inhibition was measured in HPMECs. In vivo, Snai1 expression was decreased in neonatal female lungs compared to males at P7. Increased Snai1 expression was seen in male HPMECs upon exposure to hyperoxia in vitro. Treatment with the miR-30a mimic decreased Snai1 expression in HPMECs, while miR-30a inhibition significantly increased Snai1 expression in HPMECs. siRNA-mediated loss of Hif-1α expression in HPMECs decreased miR-30a expression. Hif-1α may lead to differential sex-specific miR-30a expression and may contribute to protection from hyperoxic lung injury in female neonatal mice through decreased Snai1 expression.

Claudin Family Participates in the Pathogenesis of Inflammatory Bowel Diseases and Colitis-Associated Colorectal Cancer

Claudins are a multigene transmembrane protein family comprising at least 27 members. In gastrointestinal tract, claudins are mainly located in the intestinal epithelia; many types of claudins form a network of strands in tight junction plaques within the intercellular space of neighboring epithelial cells and build paracellular selective channels, while others act as signaling proteins and mediates cell behaviors. Claudin dysfunction may contribute to epithelial permeation disorder and multiple intestinal diseases. Over recent years, the importance of claudins in the pathogenesis of inflammatory bowel diseases (IBD) has gained focus and is being investigated. This review analyzes the expression pattern and regulatory mechanism of claudins based on existing evidence and elucidates the fact that claudin dysregulation correlates with increased intestinal permeability, sustained activation of inflammation, epithelial-to-mesenchymal transition (EMT), and tumor progression in IBD as well as consequent colitis-associated colorectal cancer (CAC), possibly shedding new light on further etiologic research and clinical treatments.

Mechanism of Low Expression of miR-30a-5p on Epithelial-Mesenchymal Transition and Metastasis in Ovarian Cancer

Metastasis of ovarian cancer is regulated by microRNAs. This study focused on the effects of miR-30a-5p on ovarian cancer migration and invasion. Our results showed that the miR-30a-5p and mucin type O-glycan biosynthesis are closely related to ovarian cancer, and that miR-30a-5p was downregulated in ovarian cancer cells. miR-30a-5p overexpression reduced cell viability and inhibited migration and invasion in HO-8910 and HO-8910PM cells. S phase kinase-associated protein 2 (SKP2), B cell lymphoma 9 (BCL9), and NOTHC1 are direct target genes of miR-30a-5p. MTDH, SKP2, BCL9, and NOTCH1 genes were overexpressed in ovarian cancer cells, and they are direct target genes of miR-30a-5p. miR-30a-5p overexpression inhibited epithelial-mesenchymal transition (EMT) process, while upregulation of SKP2, BCL9, and NOTCH1 gene expression levels reduced the inhibition of EMT process by miR-30a-5p. miR-30a-5p was lowly expressed in ovarian cancer, and such a phenomenon is related to ovarian cancer metastasis. miR-30a-5p might inhibit the migration and invasion of ovarian cancer cells by downregulating the expression of SKP2, BCL9, and NOTCH1 genes.

Claudin1 promotes the proliferation, invasion and migration of nasopharyngeal carcinoma cells by upregulating the expression and nuclear entry of β-catenin

The aim of the present study was to measure the expression of Claudin (CLDN) 1 in nasopharyngeal carcinoma (NPC) and to determine its biological function and mechanism of action. Reverse transcription-quantitative polymerase chain reaction and western blotting were performed to measure the expression of CLDN1 mRNA and protein, respectively, in the immortalized human nasopharyngeal epithelial cell line NP69 and NPC-TW01 cells. Subsequently, small interfering RNA against CLDN1 and the LV-GFP-PURO-CLDN1 lentivirus were transfected into NPC-TW01 cells. Western blotting was used to determine the effects of CLDN1 down- and upregulation on the expression of the epithelial mesenchymal transition (EMT) markers E-cadherin and vimentin. In addition, the effect of CLDN1 on the expression of β-Catenin was determined. The results demonstrated that levels of CLDN1 mRNA and protein in NPC cells were significantly higher than in NP69 cells. Furthermore, the downregulation of CLDN1 inhibited the proliferation, invasion and migration of NPC-TW01 cells. The results of western blotting demonstrated that the downregulation of CLDN1 resulted in the upregulation of E-cadherin and inhibition of vimentin in NPC-TW01 cells. By contrast, the overexpression of CLDN1 resulted in the downregulation of E-cadherin and upregulation of vimentin in NPC-TW01 cells. The downregulation of β-catenin attenuated the cancer-promoting effect of CLDN1 on NPC-TW01 cells, whereas the upregulation of β-catenin reversed the tumor-suppressing effect of CLDN1 downregulation on NPC-TW01 cells. The results of the present study therefore demonstrate that CLDN1 expression is elevated in NPC cells. As an oncogene, CLDN1 promotes the proliferation, invasion and migration of NPC cells by upregulating the expression and nuclear entry of β-catenin.

miR‑30a‑5p inhibits the proliferation, migration and invasion of melanoma cells by targeting SOX4

MicroRNA (miR)‑30a‑5p has been reported to suppress the progression of hepatocellular cancer, renal cell carcinoma, oral cancer and gastric cancer. However, whether miR‑30a‑5p is involved in the regulation of melanoma remains unclear. The present study revealed that miR‑30a‑5p was downregulated in melanoma tissues and cell lines. Overexpression of miR‑30a‑5p significantly inhibited the proliferation, migration and invasion of melanoma cells in vitro. In addition, ectopic expression of miR‑30a‑5p delayed tumor growth in vivo. In terms of mechanism, miR‑30a‑5p targeted sex determining region Y‑box 4 (SOX4) and impeded the expression of SOX4 in melanoma cells. In addition, SOX4 was upregulated in melanoma tissues and cell lines when compared with normal tissues or cells. Furthermore, overexpression of SOX4 significantly rescued the proliferation, migration and invasion of melanoma cells transfected with miR‑30a‑5p mimics. Taken together, the results of the present study demonstrated that miR‑30a‑5p suppressed the proliferation, migration and invasion of melanoma cells in SOX4‑dependent manner.

Circulating miR-30a-5p as a prognostic biomarker of left ventricular dysfunction after acute myocardial infarction

Left ventricular (LV) dysfunction after acute myocardial infarction (AMI) is associated with an increased risk of heart failure (HF) development. Diverse microRNAs (miRNAs) have been shown to appear in the bloodstream following various cardiovascular events. The aim of this study was to identify prognostic miRNAs associated with LV dysfunction following AMI. Patients were divided into subgroups comprising patients who developed or not LV dysfunction within six months of the infarction. miRNA profiles were determined in plasma and serum samples of the patients on the first day of AMI. Levels of 14 plasma miRNAs and 16 serum miRNAs were significantly different in samples from AMI patients who later developed LV dysfunction compared to those who did not. Two miRNAs were up-regulated in both types of material. Validation in an independent group of patients, using droplet digital PCR (ddPCR) confirmed that miR-30a-5p was significantly elevated on admission in those patients who developed LV dysfunction and HF symptoms six months after AMI. A bioinformatics analysis indicated that miR-30a-5p may regulate genes involved in cardiovascular pathogenesis. This study demonstrates, for the first time, a prognostic value of circulating miR-30a-5p and its association with LV dysfunction and symptoms of HF after AMI.

Functional Role of Non-Coding RNAs during Epithelial-To-Mesenchymal Transition

Epithelial-to-mesenchymal transition (EMT) is a key biological process involved in a multitude of developmental and pathological events. It is characterized by the progressive loss of cell-to-cell contacts and actin cytoskeletal rearrangements, leading to filopodia formation and the progressive up-regulation of a mesenchymal gene expression pattern enabling cell migration. Epithelial-to-mesenchymal transition is already observed in early embryonic stages such as gastrulation, when the epiblast undergoes an EMT process and therefore leads to the formation of the third embryonic layer, the mesoderm. Epithelial-to-mesenchymal transition is pivotal in multiple embryonic processes, such as for example during cardiovascular system development, as valve primordia are formed and the cardiac jelly is progressively invaded by endocardium-derived mesenchyme or as the external cardiac cell layer is established, i.e., the epicardium and cells detached migrate into the embryonic myocardial to form the cardiac fibrous skeleton and the coronary vasculature. Strikingly, the most important biological event in which EMT is pivotal is cancer development and metastasis. Over the last years, understanding of the transcriptional regulatory networks involved in EMT has greatly advanced. Several transcriptional factors such as Snail, Slug, Twist, Zeb1 and Zeb2 have been reported to play fundamental roles in EMT, leading in most cases to transcriptional repression of cell⁻cell interacting proteins such as ZO-1 and cadherins and activation of cytoskeletal markers such as vimentin. In recent years, a fundamental role for non-coding RNAs, particularly microRNAs and more recently long non-coding RNAs, has been identified in normal tissue development and homeostasis as well as in several oncogenic processes. In this study, we will provide a state-of-the-art review of the functional roles of non-coding RNAs, particularly microRNAs, in epithelial-to-mesenchymal transition in both developmental and pathological EMT.

Ascites-Derived Extracellular microRNAs as Potential Biomarkers for Ovarian Cancer

Ovarian cancer as the most fatal gynecological malignancy is often manifested by excessive fluid accumulation known as ascites or effusion. Ascites-derived microRNAs (miRNAs) may be closely associated with ovarian cancer progression. However, our knowledge of their roles, altered expression, and clinical outcomes remained limited. In this study, large-scale expression profiling of 754 human miRNAs was performed using real-time quantitative polymerase chain reaction and 384-well TaqMan array human miRNA A and B cards to identify differentially expressed miRNAs between extracellular fraction of the ascitic fluid associated with high-grade serous ovarian carcinomas and control plasma. Of the 754 miRNAs, 153 were significantly differentially expressed relative to the controls. Expression of 7 individual miRNAs (miR-200a, miR-200b, miR-200c, miR-141, miR-429, miR-1290, and miR-30a-5p) was further validated in extended sample sets, including serous, endometrioid, and mucinous subtypes. All miR-200 family members and miR-1290 were conspicuously overexpressed, while miR-30a-5p was only weakly overexpressed. The ability of miRNAs expression to discriminate the pathological samples from the controls was strong. Receiver operating characteristic curve analyses found area under the curve (AUC) values of 1.000 for miR-200a, miR-200c, miR-141, miR-429, and miR-1290 and of AUC 0.996 and 0.885 for miR-200b and miR-30a-5p, respectively. Preliminary survival analyses indicated low expression level of miR-200b as significantly related to longer overall survival (hazard ratio [HR]: 0.25, mean survival 44 months), while high expression level was related to poor overall survival (HR: 4.04, mean survival 24 months). Our findings suggested that ascites-derived miRNAs should be further explored and evaluated as potential diagnostic and prognostic biomarkers for ovarian cancer.

MicroRNAs in Smoking-Related Carcinogenesis: Biomarkers, Functions, and Therapy

Long-term heavy cigarette smoking is a well-known high-risk factor for carcinogenesis in various organs such as the head and neck, lungs, and urinary bladder. Furthermore, cigarette smoking can systemically accelerate aging, and as the result, promoting carcinogenesis via changing the host microenvironment. Various inflammatory factors, hormones, and chemical mediators induced by smoking mediate carcinoma-related molecules and induce carcinogenesis. MicroRNAs (miRNAs) are a family of short noncoding RNA molecules that bind to mRNAs and inhibit their expression. Cigarette smoke induces the expression of various miRNAs, many of which are known to function in the post-transcriptional silencing of anticancer molecules, thereby leading to smoking-induced carcinogenesis. Analysis of expression profiles of smoking-induced miRNAs can help identify biomarkers for the diagnosis and prognosis of smoking-related cancers and prediction of therapeutic responses, as well as revealing promising therapeutic targets. Here, we introduce the most recent and useful findings of miRNA analyses focused on lung cancer and urinary bladder cancer, which are strongly associated with cigarette smoking, and discuss the utility of miRNAs as clinical biomarkers.