miR-17-92 cluster promotes cholangiocarcinoma growth: evidence for PTEN as downstream target and IL-6/Stat3 as upstream activator

miRNAs Role in Wilms tumor pathogenesis: Signaling pathways interplay

Wilms' tumors (WTs) are the most common type of kidney tumor in children, and a negative outlook is generally associated with widespread anaplastic. MicroRNAs (miRNAs) are crucial in the development of WT by regulating the expression of specific genes. There is an increasing amount of research that connects the dysregulation of miRNAs to the development of various renal illnesses. The conditions encompassed are renal fibrosis, renal cancers, and chronic and polycystic kidney disease. Dysregulation of several important miRNAs, either oncogenic or tumor-suppressing, has been found in WT. The present state of knowledge on the involvement of dysregulated miRNAs in the progression of WT is summarized in this review.

Circulating miR-122-5p, miR-92a-3p, and miR-18a-5p as Potential Biomarkers in Human Liver Transplantation Follow-Up

The requirement of blood-circulating sensitive biomarkers for monitoring liver transplant (LT) is currently a necessary step aiming at the reduction of standard invasive protocols, such as liver biopsy. In this respect, the main objective of this study is to assess circulating microRNA (c-miR) changes in recipients' blood before and after LT and to correlate their blood levels with gold standard biomarkers and with outcomes such as rejection or complications after graft. An miR profile was initially performed; then, the most deregulated miRs were validated by RT-qPCR in 14 recipients pre- and post-LT and compared to a control group of 24 nontransplanted healthy subjects. MiR-122-5p, miR-92a-3p, miR-18a-5p, and miR-30c-5p, identified in the validation phase, were also analyzed considering an additional 19 serum samples collected from LT recipients and focusing on different follow-up (FU) times. The results showed significant, FU-related changes in c-miRs. In particular, miR-122-5p, miR-92a-3p, and miR-18a-5p revealed the same trend after transplantation and an increase in their level was found in patients with complications, independently from FU times. Conversely, the variations in the standard haemato-biochemical parameters for liver function assessment were not significant in the same FU period, confirming the importance of c-miRs as potential noninvasive biomarkers for monitoring patients' outcomes.

Criteria for preclinical models of cholangiocarcinoma: scientific and medical relevance

Cholangiocarcinoma (CCA) is a rare malignancy that develops at any point along the biliary tree. CCA has a poor prognosis, its clinical management remains challenging, and effective treatments are lacking. Therefore, preclinical research is of pivotal importance and necessary to acquire a deeper understanding of CCA and improve therapeutic outcomes. Preclinical research involves developing and managing complementary experimental models, from in vitro assays using primary cells or cell lines cultured in 2D or 3D to in vivo models with engrafted material, chemically induced CCA or genetically engineered models. All are valuable tools with well-defined advantages and limitations. The choice of a preclinical model is guided by the question(s) to be addressed; ideally, results should be recapitulated in independent approaches. In this Consensus Statement, a task force of 45 experts in CCA molecular and cellular biology and clinicians, including pathologists, from ten countries provides recommendations on the minimal criteria for preclinical models to provide a uniform approach. These recommendations are based on two rounds of questionnaires completed by 35 (first round) and 45 (second round) experts to reach a consensus with 13 statements. An agreement was defined when at least 90% of the participants voting anonymously agreed with a statement. The ultimate goal was to transfer basic laboratory research to the clinics through increased disease understanding and to develop clinical biomarkers and innovative therapies for patients with CCA.

SLU7: A New Hub of Gene Expression Regulation—From Epigenetics to Protein Stability in Health and Disease

SLU7 (Splicing factor synergistic lethal with U5 snRNA 7) was first identified as a splicing factor necessary for the correct selection of 3′ splice sites, strongly impacting on the diversity of gene transcripts in a cell. More recent studies have uncovered new and non-redundant roles of SLU7 as an integrative hub of different levels of gene expression regulation, including epigenetic DNA remodeling, modulation of transcription and protein stability. Here we review those findings, the multiple factors and mechanisms implicated as well as the cellular functions affected. For instance, SLU7 is essential to secure liver differentiation, genome integrity acting at different levels and a correct cell cycle progression. Accordingly, the aberrant expression of SLU7 could be associated with human diseases including cancer, although strikingly, it is an essential survival factor for cancer cells. Finally, we discuss the implications of SLU7 in pathophysiology, with particular emphasis on the progression of liver disease and its possible role as a therapeutic target in human cancer.

Selecting an Appropriate Experimental Animal Model for Cholangiocarcinoma Research

Cholangiocarcinoma (CCA) is a highly aggressive biliary tree malignancy with intrahepatic and extra-hepatic subtypes that differ in molecular pathogeneses, epidemiology, clinical manifestations, treatment, and prognosis. The overall prognosis and patient survival remains poor because of lack of early diagnosis and effective treatments. Preclinical in vivo studies have become increasingly paramount as they are helpful not only for the study of the fundamental molecular mechanisms of CCA but also for developing novel and effective therapeutic approaches of this fatal cancer. Recent advancements in cell and molecular biology have made it possible to mimic the pathogenicity of human CCA in chemical-mechanical, infection-induced inflammatory, implantation, and genetically engineered animal models. This review is intended to help investigators understand the particular strengths and weaknesses of the currently used in vivo animal models of human CCA and their related modeling techniques to aid in the selection of the one that is the best for their research needs.

Noncoding RNAs as sensors of tumor microenvironmental stress

The tumor microenvironment (TME) has been demonstrated to modulate the biological behavior of tumors intensively. Multiple stress conditions are widely observed in the TME of many cancer types, such as hypoxia, inflammation, and nutrient deprivation. Recently, accumulating evidence demonstrates that the expression levels of noncoding RNAs (ncRNAs) are dramatically altered by TME stress, and the dysregulated ncRNAs can in turn regulate tumor cell proliferation, metastasis, and drug resistance. In this review, we elaborate on the signal transduction pathways or epigenetic pathways by which hypoxia-inducible factors (HIFs), inflammatory factors, and nutrient deprivation in TME regulate ncRNAs, and highlight the pivotal roles of TME stress-related ncRNAs in tumors. This helps to clarify the molecular regulatory networks between TME and ncRNAs, which may provide potential targets for cancer therapy.

MiR-150 Attenuates Maladaptive Cardiac Remodeling Mediated by Long Noncoding RNA MIAT and Directly Represses Profibrotic Hoxa4

BACKGROUND

MicroRNA-150 (miR-150) plays a protective role in heart failure (HF). Long noncoding RNA, myocardial infarction-associated transcript (MIAT) regulates miR-150 function in vitro by direct interaction. Concurrent with miR-150 downregulation, MIAT is upregulated in failing hearts, and gain-of-function single-nucleotide polymorphisms in MIAT are associated with increased risk of myocardial infarction (MI) in humans. Despite the correlative relationship between MIAT and miR-150 in HF, their in vivo functional relationship has never been established, and molecular mechanisms by which these 2 noncoding RNAs regulate cardiac protection remain elusive.

METHODS

We use MIAT KO (knockout), Hoxa4 (homeobox a4) KO, MIAT TG (transgenic), and miR-150 TG mice. We also develop DTG (double TG) mice overexpressing MIAT and miR-150. We then use a mouse model of MI followed by cardiac functional, structural, and mechanistic studies by echocardiography, immunohistochemistry, transcriptome profiling, Western blotting, and quantitative real-time reverse transcription-polymerase chain reaction. Moreover, we perform expression analyses in hearts from patients with HF. Lastly, we investigate cardiac fibroblast activation using primary adult human cardiac fibroblasts and in vitro assays to define the conserved MIAT/miR-150/HOXA4 axis.

RESULTS

Using novel mouse models, we demonstrate that genetic overexpression of MIAT worsens cardiac remodeling, while genetic deletion of MIAT protects hearts against MI. Importantly, miR-150 overexpression attenuates the detrimental post-MI effects caused by MIAT. Genome-wide transcriptomic analysis of MIAT null mouse hearts identifies Hoxa4 as a novel downstream target of the MIAT/miR-150 axis. Hoxa4 is upregulated in cardiac fibroblasts isolated from ischemic myocardium and subjected to hypoxia/reoxygenation. HOXA4 is also upregulated in patients with HF. Moreover, Hoxa4 deficiency in mice protects the heart from MI. Lastly, protective actions of cardiac fibroblast miR-150 are partially attributed to the direct and functional repression of profibrotic Hoxa4.

CONCLUSIONS

Our findings delineate a pivotal functional interaction among MIAT, miR-150, and Hoxa4 as a novel regulatory mechanism pertinent to ischemic HF.

An Overview of Mesenchymal Stem Cell-based Therapy Mediated by Noncoding RNAs in the Treatment of Neurodegenerative Diseases

Mesenchymal stem cells (MSCs) have become a promising tool for neurorestorative therapy of neurodegenerative diseases (NDDs), which are mainly characterized by the progressive and irreversible loss of neuronal structure and function in the central or peripheral nervous system. Recently, studies have reported that genetic manipulation mediated by noncoding RNAs (ncRNAs) can increase survival and neural regeneration of transplanted MSCs, offering a new strategy for clinical translation. In this review, we summarize the potential role and regulatory mechanism of two major types of ncRNAs, including microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), during the neurogenesis of MSCs with gene expression profile analyses. We also overview the realization of MSC-based therapy mediated by ncRNAs in the treatment of spinal cord injury, stroke, Alzheimer's disease and peripheral nerve injury. It is expected that ncRNAs will become promising therapeutic targets for NDD on stem cells, while the underlying mechanisms require further exploration.

Searching for a Putative Mechanism of RIZ2 Tumor-Promoting Function in Cancer Models

Positive Regulatory Domain (PRDM) gene family members commonly express two main molecular variants, the PR-plus isoform usually acting as tumor suppressor and the PR-minus one functioning as oncogene. Accordingly, PRDM2/RIZ encodes for RIZ1 (PR-plus) and RIZ2 (PR-minus). In human cancers, genetic or epigenetic modifications induce RIZ1 silencing with an expression level imbalance in favor of RIZ2 that could be relevant for tumorigenesis. Additionally, in estrogen target cells and tissues, estradiol increases RIZ2 expression level with concurrent increase of cell proliferation and survival. Several attempts to study RIZ2 function in HeLa or MCF-7 cells by its over-expression were unsuccessful. Thus, we over-expressed RIZ2 in HEK-293 cells, which are both RIZ1 and RIZ2 positive but unresponsive to estrogens. The forced RIZ2 expression increased cell viability and growth, prompted the G2-to-M phase transition and organoids formation. Accordingly, microarray analysis revealed that RIZ2 regulates several genes involved in mitosis. Consistently, RIZ silencing in both estrogen-responsive MCF-7 and -unresponsive MDA-MB-231 cells induced a reduction of cell proliferation and an increase of apoptosis rate. Our findings add novel insights on the putative RIZ2 tumor-promoting functions, although additional attempts are warranted to depict the underlying molecular mechanism.

MicroRNAs in cartilage development and dysplasia

Small regulatory microRNAs (miRNAs) post-transcriptionally suppress gene expression. MiRNAs expressed in skeletal progenitor cells and chondrocytes regulate diverse aspects of cellular function and thus skeletal development. In this review, we discuss the role of miRNAs in skeletal development, particularly focusing on those whose physiological roles were revealed in vivo. Deregulation of miRNAs is found in multiple acquired diseases such as cancer; however congenital diseases caused by mutations in miRNA genes are very rare. Among those are mutations in miR-140 and miR-17~92 miRNAs which cause skeletal dysplasias. We also discuss pathological mechanisms underlining these skeletal dysplasias.

Dysregulation of microRNA in cholangiocarcinoma identified through a meta-analysis of microRNA profiling

BACKGROUND

In the past decades, the potential of microRNA (miRNA) in cancer diagnostics and prognostics has gained a lot of interests. In this study, a meta-analysis was conducted upon the pooled miRNA microarray data of cholangiocarcinoma (CCA).

AIM

To identify differentially expressed (DE) miRNAs and perform functional analyses in order to gain insights to understanding miRNA-target interactions involved in tumorigenesis pathways of CCA.

METHODS

Raw data from 8 CCA miRNA microarray datasets, consisting of 443 samples in total, were integrated and statistically analyzed to identify DE miRNAs via comparison of levels of miRNA expression between CCA and normal bile duct samples using t-tests (P < 0.001). The 10-fold cross validation was performed in order to increase the robustness of the t-test results.

RESULTS

Our data showed 70 up-regulated and 48 down-regulated miRNAs in CCA. Gene Ontology and pathway enrichment analyses revealed that mRNA targets of DE miRNAs were significantly involved in several biological processes. The most prominent dysregulated pathways included phosphatidylinositol-3 kinases/Akt, mitogen-activated protein kinase and Ras signaling pathways.

CONCLUSION

DE miRNAs found in our meta-analysis revealed dysregulation in major cancer pathways involved in the development of CCA. These results indicated the necessity of understanding the miRNA-target interactions and the significance of dysregulated miRNAs in terms of diagnostics and prognostics of cancers.

EGF-mediated reduced miR-92a-1-5p controls HTR-8/SVneo cell invasion through activation of MAPK8 and FAS which in turn increase MMP-2/-9 expression

The members of human miR-17-92 cluster are implicated in several cancers and are known to increase cancer cells invasiveness. The present study reports reduced expression of miR-92a-1-5p in EGF treated HTR-8/SVneo trophoblastic cells by NGS and qRT-PCR. Overexpression of miR-92a-1-5p led to significantly reduced EGF-mediated HTR-8/SVneo cells invasion. MAPK8 and FAS were predicted to be miR-92a-1-5p targets, and confirmed to be reduced by qRT-PCR and Western blotting in trophoblast cells overexpressing miR-92a-1-5p. The binding of miR-92a-1-5p to MAPK8 and FAS 3'-UTR was confirmed by Luciferase reporter assay and Rescue assay. EGF increases MMP-2 & MMP-9 expression and reduces TIMP1 expression in HTR-8/SVneo cells. Inhibition of MAPK8 (by SP600125) reduced EGF-mediated MMP-9/TIMP1 ratio and invasion. Similarly, silencing of FAS by siRNA reduced EGF-mediated MMP-2/TIMP1 ratio and invasion. Treatment of HTR-8/SVneo cells with STAT1/3 inhibitors or siRNAs led to loss of EGF-mediated reduction in miR-92a-1-5p levels. Inserting the predicted binding sites of STAT3 present in promoter region of miR-92a-1-5p upstream of Luciferase promoter reduced its expression in presence of STAT3 expression vector. Thus, EGF leads to reduced miR-92a-1-5p expression which may be regulated by STAT1/STAT3 and controls HTR-8/SVneo cells invasion by targeting MAPK8 and FAS, which in turn increases MMP-2/MMP-9 expression.

In Vivo Models for Cholangiocarcinoma-What Can We Learn for Human Disease?

Cholangiocarcinoma (CCA) comprises a heterogeneous group of primary liver tumors. They emerge from different hepatic (progenitor) cell populations, typically via sporadic mutations. Chronic biliary inflammation, as seen in primary sclerosing cholangitis (PSC), may trigger CCA development. Although several efforts were made in the last decade to better understand the complex processes of biliary carcinogenesis, it was only recently that new therapeutic advances have been achieved. Animal models are a crucial bridge between in vitro findings on molecular or genetic alterations, pathophysiological understanding, and new therapeutic strategies for the clinic. Nevertheless, it is inherently difficult to recapitulate simultaneously the stromal microenvironment (e.g., immune-competent cells, cholestasis, inflammation, PSC-like changes, fibrosis) and the tumor biology (e.g., mutational burden, local growth, and metastatic spread) in an animal model, so that it would reflect the full clinical reality of CCA. In this review, we highlight available data on animal models for CCA. We discuss if and how these models reflect human disease and whether they can serve as a tool for understanding the pathogenesis, or for predicting a treatment response in patients. In addition, open issues for future developments will be discussed.

Role of noncoding RNAs in cholangiocarcinoma (Review)

Cholangiocarcinoma (CCA) is a malignant tumour originating from biliary epithelial cells, and is increasing in incidence. Radical surgery is the main treatment. However, the pathogenesis of CCA is unclear. Noncoding RNAs (ncRNAs) are non‑protein‑coding RNAs produced by genomic transcription that include microRNAs (miRNAs), circular RNAs (circRNAs) and long noncoding RNAs (lncRNAs). They play important roles in gene expression, epigenetic modification, cell proliferation, differentiation and reproduction. ncRNAs also serve key roles in cancer development. Numerous studies have been carried out on ncRNAs, and associated publications have shown that ncRNAs are closely associated with the physiological and pathological mechanisms of CCA. The findings of these studies can provide new insights into the diagnosis, treatment and prognosis of CCA. The present review summarizes the pathophysiological mechanisms of different types of ncRNAs, including miRNAs, circRNAs and lncRNAs in CCA, and their applications in the diagnosis and treatment of CCA.

Bile-derived circulating extracellular miR-30d-5p and miR-92a-3p as potential biomarkers for cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma (CCA) is from cholangiocytes, and therefore bile is a potentially rich source of biomarkers for CCA. The aim of the study was to identify and validate microRNAs (miRNAs) in bile samples that are differentially expressed between benign biliary disease (BBD) and CCA.

METHODS

Bile samples from 106 patients with obstructive biliary disease were allocated consecutively to a discovery set (10 patients with BBD and 11 with CCA) and then a validation set (48 patients with BBD and 37 with CCA). An miRNA microarray platform was used to screen 1209 miRNAs in the discovery set. Quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) was used to validate the profiling results in the discovery and validation sets. In addition, the levels of carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) were determined from patient serum samples.

RESULTS

Microarray profiling showed that miR-30d-5p and miR-92a-3p were significantly upregulated in bile from the CCA group compared with those from the BBD group. qRT-PCR results indicated that the expression levels of miR-30d-5p and of miR-92a-3p were significantly upregulated in the CCA group compared to the BBD group, validating the miRNA microarray results. Pathway analysis suggested that putative target genes of miR-30d-5p and of miR-92a-3p were involved in CCA-associated signalling pathways, such as Hippo, Wnt, p53, MAPK, and EGFR. Receiver operating curve analysis revealed that the areas under the curve for bile miR-30d-5p, miR-92a-3p, serum CA19-9, and CEA were 0.730, 0.652, 0.675, and 0.603, respectively, and bile miR-30d-5p showed the best diagnostic performance with a sensitivity of 81.1% and a specificity of 60.5%.

CONCLUSIONS

The levels of extracellular miR-30d-5p and miR-92a-3p in bile were significantly higher in patients with CCA than those in patients with BBD. Bile-derived circulating extracellular miR-30d-5p and miR-92a-3p are potential biomarkers for discriminating CCA from BBD.

The dual functional role of MicroRNA-18a (miR-18a) in cancer development

The polycistronic miR-17-92 cluster is instrumental in physiological processes commonly dysregulated in cancer, such as proliferation, the cell cycle, apoptosis, and differentiation. MicroRNA-18a (miR-18a) is one of the most conserved and multifunctional miRNAs in the cluster and is frequently overexpressed in malignant tumors. Altered miR-18a expression has been found in various physiological and pathological processes, including cell proliferation, apoptosis, epithelial-mesenchymal transition (EMT), tumorigenesis, cancer invasion and metastasis. In this review, we summarized the molecular basis and regulatory targets of miR-18a in cancer development. Interestingly, miR-18a has a dual functional role in either promoting or inhibiting oncogenesis in different human cancers. The differential miRNA expression in cancers of the same organ at different stages or of various subtypes suggests that this dual function of miR-18a is independent of cancer type and may be attributed to the fundamental differences in tumorigenic mechanisms. Finally, we summarized the current clinical use of miR-18a and discussed its potential uses in cancer therapy.

Integrated analysis of miRNA landscape and cellular networking pathways in stage-specific prostate cancer

Dysregulation of miRNAs has been demonstrated in several human malignancies including prostate cancer. Due to tissue limitation and variable disease progression, stage-specific miRNAs changes in prostate cancer is unknown. Using chip-based microarray, we investigated global miRNA expression in human prostate cancer LNCaP, PC3, DU145 and 22Rv1 cells representing early-stage, advanced-stage and castration resistant prostate cancer in comparison with normal prostate epithelial cells. A total of 292 miRNAs were differentially expressed with 125 upregulated and 167 downregulated. These miRNAs were involved in pathways including drug resistance drug-efflux, adipogenesis, epithelial-to-mesenchymal transition, bone metamorphosis, and Th1/Th2 signaling. Regulation of miRNAs were interlinked with upstream regulators such as Argonaut 2 (AGO2), Double-Stranded RNA-Specific Endoribonuclease (DICER1), Sjogren syndrome antigen B (SSB), neurofibromatosis 2 (NF2), and peroxisome proliferator activated receptor alpha (PPARA), activated during stage-specific disease progression. Candidate target genes and pathways dysregulated in stage-specific prostate cancer were identified using CS-miRTar database and confirmed in clinical specimens. Integrative network analysis suggested some genes targeted by miRNAs include miR-17, let7g, miR-146, miR-204, miR-205, miR-221, miR-301 and miR-520 having a major effect on their dysregulation in prostate cancer. MiRNA-microarray analysis further identified miR-130a, miR-181, miR-328, miR146 and miR-200 as a panel of novel miRNAs associated with drug resistance drug-efflux and epithelial-to-mesenchymal transition in prostate cancer. Our findings provide evidence on miRNA dysregulation and its association with key functional components in stage-specific prostate cancer.

Interleukin 6 decreases nociceptor expression of the potassium channel KV1.4 in a rat model of hand-arm vibration syndrome

Chronic muscle pain is a prominent symptom of the hand-arm vibration syndrome (HAVS), an occupational disease induced by exposure to vibrating power tools, but the underlying mechanism remains unknown. We evaluated the hypothesis that vibration induces an interleukin 6 (IL-6)-mediated downregulation of the potassium voltage-gated channel subfamily A member 4 (KV1.4) in nociceptors leading to muscle pain. Adult male rats were submitted to a protocol of mechanical vibration of the right hind limb. Twenty-four hours after vibration, muscle hyperalgesia was observed, concomitant to increased levels of IL-6 in the gastrocnemius muscle and decreased expression of KV1.4 in the dorsal root ganglia. Local injection of neutralizing antibodies against IL-6 attenuated the muscle hyperalgesia induced by vibration, whereas antisense knockdown of this channel in the dorsal root ganglia mimicked the muscle hyperalgesia observed in the model of HAVS. Finally, knockdown of the IL-6 receptor signaling subunit glycoprotein 130 (gp130) attenuated both vibration-induced muscle hyperalgesia and downregulation of KV1.4. These results support the hypothesis that IL-6 plays a central role in the induction of muscle pain in HAVS. This likely occurs through intracellular signaling downstream to the IL-6 receptor subunit gp130, which decreases the expression of KV1.4 in nociceptors.

MicroRNA-92a promotes vascular smooth muscle cell proliferation and migration through the ROCK/MLCK signalling pathway

To identify the interaction between known regulators of atherosclerosis, microRNA-92a (miR-92a), Rho-associated coiled-coil-forming kinase (ROCK) and myosin light chain kinase (MLCK), we examined their expressions during proliferation and migration of platelet-derived growth factor-BB (PDGF-BB)-regulated vascular smooth muscle cells (VSMCs), both in vivo and in vitro. During the formation of atherosclerosis plaque in mice, a parallel increase in expression levels of MLCK and miR-92a was observed while miR-92a expression was reduced in ML-7 (an inhibitor of MLCK) treated mice and in MLCK-deficient VSMCs. In vitro results indicated that both MLCK and miR-92a shared the same signalling pathway. Transfection of miR-92a mimic partially restored the effect of MLCK's deficiency and antagonized the effect of Y27632 (an inhibitor of ROCK) on the down-regulation of VSMCs activities. ML-7 increased the expression of Kruppel-like factor 4 (KLF4, a target of miR-92a), and siRNA-KLF4 increased VSMCs' activity level. Consistently, inhibition of either MLCK or ROCK enhanced the KLF4 expression. Moreover, we observed that ROCK/MLCK up-regulated miR-92a expression in VSMCs through signal transducer and activator of transcription 3 (STAT3) activation. In conclusion, the activation of ROCK/STAT3 and/or MLCK/STAT3 may up-regulate miR-92a expression, which subsequently inhibits KLF4 expression and promotes PDGF-BB-mediated proliferation and migration of VSMCs. This new downstream node in the ROCK/MLCK signalling pathway may offer a potential intervention target for treatment of atherosclerosis.

Animal models of cholangiocarcinoma

Cholangiocarcinoma (CCA) is an aggressive biliary tract malignancy with a poor overall prognosis. There is a critical need to develop effective targeted therapies for the treatment of this lethal disease. In an effort to address this challenge, preclinical in vivo studies have become paramount in understanding CCA carcinogenesis, progression, and therapy. Various CCA animal models exist including carcinogen-based models in which animals develop CCA after exposure to a carcinogen, genetically engineered mouse models in which genetic changes are induced in mice leading to CCA, murine syngeneic orthotopic models, as well as xenograft tumors derived from xenotransplantation of CCA cells, organoids, and patient-derived tissue. Each type has distinct advantages as well as shortcomings. In the ideal animal model of CCA, the tumor arises from the biliary tract in an immunocompetent host with a species-matched tumor microenvironment. Such a model would also be time-efficient, recapitulate the genetic and histopathological features of human CCA, and predict therapeutic response in humans. Recently developed biliary tract transduction and orthotopic syngeneic transplant mouse models encompass several of these elements. Herein, we review the different animal models of CCA, their advantages and deficiencies, as well as features which mimic human CCA.

MicroRNA-451 Inhibits Migration of Glioblastoma while Making It More Susceptible to Conventional Therapy

Malignant glioblastoma (GBM, glioma) is the most common and aggressive primary adult brain tumor. The prognosis of GBM patients remains poor, despite surgery, radiation and chemotherapy. The major obstacles for successful remedy are invasiveness and therapy resistance of GBM cells. Invasive glioma cells leave primary tumor core and infiltrate surrounding normal brain leading to inevitable recurrence, even after surgical resection, radiation and chemotherapy. Therapy resistance allowing for selection of more aggressive and resistant sub-populations including GBM stem-like cells (GSCs) upon treatment is another serious impediment to successful treatment. Through their regulation of multiple genes, microRNAs can orchestrate complex programs of gene expression and act as master regulators of cellular processes. MicroRNA-based therapeutics could thus impact broad cellular programs, leading to inhibition of invasion and sensitization to radio/chemotherapy. Our data show that miR-451 attenuates glioma cell migration in vitro and invasion in vivo. In addition, we have found that miR-451 sensitizes glioma cells to conventional chemo- and radio-therapy. Our data also show that miR-451 is regulated in vivo by AMPK pathway and that AMPK/miR-451 loop has the ability to switch between proliferative and migratory pattern of glioma cells behavior. We therefore postulate that AMPK/miR-451 negative reciprocal feedback loop allows GBM cells/GSCs to adapt to tumor “ecosystem” by metabolic and behavioral flexibility, and that disruption of such a loop reduces invasiveness and diminishes therapy resistance.

The MicroRNA Family Both in Normal Development and in Different Diseases: The miR-17-92 Cluster

An increasing number of research studies over recent years have focused on the function of microRNA (miRNA) molecules which have unique characteristics in terms of structure and function. They represent a class of endogenous noncoding single-strand small molecules. An abundance of miRNA clusters has been found in the genomes of various organisms often located in a polycistron. The miR-17-92 family is among the most famous miRNAs and has been identified as an oncogene. The functions of this cluster, together with the seven individual molecules that it comprises, are most related to cancers, so it would not be surprising that they are considered to have involvement in the development of tumors. The miR-17-92 cluster is therefore expected not only to be a tumor marker, but also to perform an important role in the early diagnosis of those diseases and possibly also be a target for tumor biotherapy. The miR-17-92 cluster affects the development of disease by regulating many related cellular processes and multiple target genes. Interestingly, it also has important roles that cannot be ignored in disease of the nervous system and circulation and modulates the growth and development of bone. Therefore, it provides new opportunities for disease prevention, clinical diagnosis, prognosis, and targeted therapy. Here we review the role of the miR-17-92 cluster that has received little attention in relation to neurological diseases, cardiac diseases, and the development of bone and tumors.

Inhibition of miR-10a-5p suppresses cholangiocarcinoma cell growth through downregulation of Akt pathway

Backgrounds

Cholangiocarcinoma (CCA) is epithelial cell malignancy with very poor prognosis. A lot of patients were diagnosed at advanced stage of CCA and no risk factors were identified. There are limited treatment options available for the management of CCA patients. It is urgent to develop effective targeted therapies for the treatment of CCA. miRNAs are small noncoding RNAs that negatively regulate the target genes. In this study, we investigated the role and mechanism of miR-10a-5p in CCA.

Methods

Human CCA cell lines (CCLP1 and SG-231) were transfected with miR-10a-5p mimic or miR-10a-5p inhibitor. qRT-PCR was performed to detect the miR-10a-5p level. Proliferation, colony formation, and apoptosis were analyzed. Luciferase reporter assay was used to explore the targeting of miR-10a-5p on PTEN. For in vivo tumorigenesis assay, CCLP1 cells with stable knockdown of miR-10a-5p or control CCLP1 cells were injected subcutaneously into the flank of the SCID mice and animals were monitored for tumor growth.

Results

miR-10a-5p expression was significantly upregulated in human CCA cell lines (CCLP1 and SG-231). Inhibition of miR-10a-5p significantly suppressed the proliferation and induced apoptosis in CCLP1 and SG-231. PTEN is a direct target of miR-10a-5p in CCA cells.

Conclusion

Inhibition of miR-10a-5p can decrease CCA cells growth by downregulation of Akt pathway. These results indicate that miR-10a-5p may serve as a potential target for the treatment of CCA and help to develop effective therapeutic strategies.

FBXL14 abolishes breast cancer progression by targeting CDCP1 for proteasomal degradation

Understanding the molecular mechanisms that underlie the aggressive behavior and relapse of breast cancer may help in the development of novel therapeutic interventions. CUB-domain-containing protein 1 (CDCP1), a transmembrane adaptor protein, is highly maintained and required in the context of cellular metastatic potential in triple-negative breast cancer (TNBC). For this reason, gene expression levels of CDCP1 have been considered as a prognostic marker in TNBC. However, not rarely, transcript levels of genes do not reflect always the levels of proteins, due to the post-transcriptional regulation. Here we show that miR-17/20a control the FBXL14 E3 ligase, establishing FBXL14 as an upstream regulator of the CDCP1 pathway. FBXL14 acts as an novel interaction partner of CDCP1, and facilitates its ubiquitination and proteasomal degradation with an enhanced capacity to suppress CDCP1 protein stability that eventually prevents CDCP1 target genes involved in breast cancer metastasis. Our findings first time uncovers the regulatory mechanism of CDCP-1 protein stabilization, more predictable criteria than gene expression levels for prognosis of breast cancer patients.

Clustered miRNAs and their role in biological functions and diseases

MicroRNAs (miRNAs) are endogenous, small non-coding RNAs known to regulate expression of protein-coding genes. A large proportion of miRNAs are highly conserved, localized as clusters in the genome, transcribed together from physically adjacent miRNAs and show similar expression profiles. Since a single miRNA can target multiple genes and miRNA clusters contain multiple miRNAs, it is important to understand their regulation, effects and various biological functions. Like protein-coding genes, miRNA clusters are also regulated by genetic and epigenetic events. These clusters can potentially regulate every aspect of cellular function including growth, proliferation, differentiation, development, metabolism, infection, immunity, cell death, organellar biogenesis, messenger signalling, DNA repair and self-renewal, among others. Dysregulation of miRNA clusters leading to altered biological functions is key to the pathogenesis of many diseases including carcinogenesis. Here, we review recent advances in miRNA cluster research and discuss their regulation and biological functions in pathological conditions.

Decrease of miR-622 expression promoted the proliferation, migration and invasion of cholangiocarcinoma cells by targeting regulation of c-Myc

OBJECTIVE

To explore the mechanism of miR-622 in regulating the proliferation, migration and invasion of cholangiocarcinoma (CCA) cells.

MATERIALS AND METHODS

Quantitative real-time PCR was conducted to measure the expression of miR-622 and c-Myc in CCA tissues and cell lines. Protein level of c-Myc was measured by Western blot. The effect of miR-622 on cell proliferation, migration and invasion was analyzed by MTT assay and Transwell chamber migration assay. Luciferase reporter assay was performed to measure the effect of miR-622 on c-Myc.

RESULTS

miR-622 expression was downregulated in both CCA tissues and cell lines, while c-Myc expression was uregulated. Overexpression of miR-622 in CCA cells was statistically correlated with a decrease of cell proliferation, migration and invasion, while inhibition of miR-622 made an inverse result. We also proved c-Myc was identified as a target gene of miR-622 in CCA. Moreover, we found overexpression of c-Myc can strengthen the effects of miR-622 on the proliferation, migration and invasion of CCA cells.

CONCLUSION

Decrease of miR-622 promotes the proliferation, migration and invasion of CCA cells by directly targeting c-Myc.

MiR-17-5p and miR-20a promote chicken cell proliferation at least in part by upregulation of c-Myc via MAP3K2 targeting

The miR-17-92 cluster has been well studied in mammals but less extensively studied in birds. Here, we demonstrated that miR-17-92 cluster overexpression promoted the proliferation of DF1 cells and immortalized chicken preadipocytes (ICPA-1), and miR-17-5p and miR-20a, members of the miR-17-92 cluster, targeted MAP3K2. Further analysis showed that MAP3K2 overexpression reduced the proliferation of DF1 and ICPA-1 cells and attenuated the promotive effect of the miR-17-92 cluster on cell proliferation. Downstream gene expression analysis of the MAPK signalling pathway showed that MAP3K2 overexpression decreased c-Myc expression; in contrast, MAP3K2 knockdown using RNA interference and miR-17-92 cluster overexpression increased c-Myc expression. Furthermore, c-Myc overexpression promoted miR-17-92 cluster expression and DF1 cell proliferation. Taken together, these data indicated that miR-17-92 promotes chicken cell proliferation at least in part by the upregulation of c-Myc via targeting MAP3K2, and the miR-17-92 cluster, c-Myc and E2F1 form a complex regulatory network in chicken cell proliferation.

Involvement of inflammation and its related microRNAs in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most commonly diagnosed type of cancer. The tumor inflammatory microenvironment regulates almost every step towards liver tumorigenesis and subsequent progression, and regulation of the inflammation-related signaling pathways, cytokines, chemokines and non-coding RNAs influences the proliferation, migration and metastasis of liver tumor cells. Inflammation fine-tunes the cancer microenvironment to favor epithelial-mesenchymal transition, in which cancer stem cells maintain tumorigenic potential. Emerging evidence points to inflammation-related microRNAs as crucial molecules to integrate the complex cellular and molecular crosstalk during HCC progression. Thus understanding the mechanisms by which inflammation regulates microRNAs might provide novel and admissible strategies for preventing, diagnosing and treating HCC. In this review, we will update three hypotheses of hepatocarcinogenesis and elaborate the most predominant inflammation signaling pathways, i.e. IL-6/STAT3 and NF-κB. We also try to summarize the crucial tumor-promoting and tumor-suppressing microRNAs and detail how they regulate HCC initiation and progression and collaborate with other critical modulators in this review.

MiR-92a promotes stem cell-like properties by activating Wnt/β-catenin signaling in colorectal cancer

We previously reported the oncogenic function of miR-92a in colorectal cancer. This study identified that miR-92a was upregulated in chemoresistant colorectal cancer cells and tissues. Ectopic expression of miR-92a conferred resistance to 5-fluorouracil-induced apoptosis in vitro, while antagomiR-92a significantly enhanced chemosensitivity in vivo. Moreover, Overexpression of miR-92a promoted the tumor sphere formation and the expression of stem cell markers. MiR-92a overexpression also displayed higher tumourigenesis in vivo. Furthermore, we demonstrated that miR-92a upregulates the Wnt/β-catenin signaling activity via directly targeting KLF4, GSK3β and DKK3, which are multiple level negative regulators of the Wnt/β-catenin signaling cascade. In addition, our results indicate IL-6/STAT3 pathway increases miR-92a expression by directly targeting its promoter, resulting in Wnt/β-catenin signaling activation and consequent promotion of stem-like phenotypes of colorectal cancer cells. Our present results suggest the essential role of IL-6/STAT3/miR-92a/Wnt/β-catenin pathway in regulating the stem cell-like traits of colorectal cancer cells and provide a potential target for colorectal cancer therapy.

miRNA profiling for diagnosis, prognosis and stratification of cancer treatment in cholangiocarcinoma

Cholangiocarcinoma (CCA) is a lethal malignancy originating from the biliary tract epithelium. Most patients are diagnosed at an advanced stage. Even after resection with curative intent, prognosis remains poor. Previous studies have reported the evolving role of miRNAs as novel biomarkers in cancer diagnosis, prognostication and chemotherapy response. Various miRNAs, such as miR-21, miR-26, miR-122 and miR-150, have been identified as possible blood-based biomarkers for noninvasive diagnosis of CCA. Moreover, epithelial-mesenchymal transition (EMT)- and angiogenesis-associated miRNAs have been implicated in tumor cell dissemination and are able to determine clinical outcome. In fact, miRNAs involved in cell survival might even determine chemotherapy response. This review provides an overview of known miRNAs as CCA-specific biomarkers.

p53-mediated miR-18 repression activates HSF2 for IGF-IIR-dependent myocyte hypertrophy in hypertension-induced heart failure

Hypertension-induced cardiac hypertrophy and attenuated cardiac function are the major characteristics of early stage heart failure. Cardiomyocyte death in pathological cardiac conditions is the primary cause of heart failure and mortality. Our previous studies found that heat shock factor 1 (HSF1) protected cardiomyocytes from death by suppressing the IGF-IIR signaling pathway, which is critical for hypertensive angiotensin II-induced cardiomyocyte apoptosis. However, the role of heat shock factor 2 (HSF2) in hypertension-induced cardiac hypertrophy is unknown. We identified HSF2 as a miR-18 target for cardiac hypertrophy. p53 activation in angiotensin II (ANG II)-stimulated NRVMs is responsible for miR-18 downregulation both in vitro and in vivo, which triggers HSF2 expression and the activation of IGF-IIR-induced cardiomyocyte hypertrophy. Finally, we provide genetic evidence that miR-18 is required for cardiomyocyte functions in the heart based on the gene transfer of cardiac-specific miR-18 via adenovirus-associated virus 2 (AAV2). Transgenic overexpression of miR-18 in cardiomyocytes is sufficient to protect against dilated cardiomyopathy during hypertension-induced heart failure. Our results demonstrated that the p53-miR-18-HSF2-IGF-IIR axis was a critical regulatory pathway of cardiomyocyte hypertrophy in vitro and in vivo, suggesting that miR-18 could be a therapeutic target for the control of cardiac functions and the alleviation of cardiomyopathy during hypertension-induced heart failure.

miR-17-92基因簇在肿瘤发生发展中作用的研究进展

肿瘤是威胁全世界人类健康和影响社会经济的重要因素. 近年来, 随着经济的发展, 肿瘤的发病率呈明显上升趋势, 但是其病因尚未完全阐明. 越来越多的证据显示肿瘤的发生和遗传因素有关, 随着病理生理学和遗传学的发展, 许多学者认为生物标志物可以预测癌症甚至指导临床治疗. 微小RNA(microRNA, miRNA)是非编码小分子RNA, 在发育、生理、病理过程以及肿瘤发生等环节中起着重要的调节作用. miR-17-92基因簇是研究较为深入、最有特点的miRNA, 被认为是原癌基因miRNA的代表, 在多种肿瘤的发生发展中起着至关重要的作用. 本文就miR-17-92基因簇在肿瘤发生发展中的作用及功能进行综述.

Acupuncture Ameliorates Postoperative Ileus via IL-6-miR-19a-KIT Axis to Protect Interstitial Cells of Cajal

Acupuncture is a therapy effective in treating postoperative ileus (POI); its underlying mechanisms remain unclear. MicroRNAs (miRNAs) participate in inflammation and injury to the interstitial cells of Cajal (ICCs), both of which are considered to be contributors to POI. C-kit, encoding KIT, a specific marker of ICCs, is predicted to be targeted by miR-19a, an inflammation-related miRNA. Therefore, we investigated a possible link between inflammation, miR-19a, and ICCs in POI, as well as the mechanism by which these factors are affected by acupuncture. The effects of acupuncture on POI were assessed in patients after colorectal resection and in colocolic anastomosis mice. Immunofluorescence staining demonstrated that KIT[Formula: see text]/ano1[Formula: see text] ICCs dramatically decreased around the colonic incision in mice, which was negatively correlated with the pronounced increase in macrophage. However, this decrease was not due to apoptosis. IL-6R was expressed in ICCs, and IL-6 level was significantly increased, as measured by ELISA, in accompaniment with high miR-19a expression. The increase in IL-6 and miR-19a levels was negatively correlated with the decrease in KIT[Formula: see text]/ano1[Formula: see text] ICCs. A luciferase reporter assay demonstrated that miR-19a directly targeted C-kit, indicating that miR-19a caused ICC damage. Interestingly, acupuncture inhibited macrophage activation, IL-6 release, and miR-19a upregulation, while promoting KIT and ano1 restoration in ICCs. High serum miR-19a level in patients after colorectal resection was also reduced by acupuncture. Conclusively, the IL-6 released by macrophages during gastrointestinal surgery upregulated miR-19a, which downregulated KIT in ICCs and finally resulted in POI. Acupuncture can interfere with the "IL-6-miR-19a-KIT" axis, suggesting that it may be a therapeutic mechanism that works against POI.

miRNA-21 promotes proliferation and invasion of triple-negative breast cancer cells through targeting PTEN

MicroRNAs (miRNAs) are small single-stranded RNAs that bind to the 3'UTR of the mRNAs of target genes. They can target multiple genes and regulate translation or degradation of the mRNA. miRNAs target genes in a tissue-specific manner, and the role of a particular miRNA varies according to tumor origin or even subtype within the same cancer. This study evaluated the effect of miR-21 expression in triple-negative breast cancer (TNBC) tissues and MDA-MB-468, a cell line derived from TNBC tissues. miR-21 was consistently upregulated in TNBC and MDA-MB-468 cells compared to normal tissues. Inhibition of miR-21 by miR-21 antisense oligonucleotides decreased the proliferation, viability, and invasiveness of MDA-MB-468 cells and enhanced apoptosis. Furthermore, we confirmed that PTEN was downregulated by miR-21 in MDA-MB-468 cells. The results indicated that PTEN may mediate the oncogenic properties of miR-21 in TNBC. In summary, miR-21 was upregulated in TNBC tissues and cells, and promoted the proliferation and invasion of MDA-MB-468 cells, but negatively regulated the expression of PTEN protein. Inhibition of miR-21 or overexpression of PTEN protein could be promising strategies for the treatment of patients with TNBC.

Deregulated MicroRNAs in Biliary Tract Cancer: Functional Targets and Potential Biomarkers

Biliary tract cancer (BTC) is still a fatal disease with very poor prognosis. The lack of reliable biomarkers for early diagnosis and of effective therapeutic targets is a major demanding problem in diagnosis and management of BTC. Due to the clinically silent and asymptomatic characteristics of the tumor, most patients are diagnosed at an already advanced stage allowing only for a palliative therapeutic approach. MicroRNAs are small noncoding RNAs well known to regulate various cellular functions and pathologic events including the formation and progression of cancer. Over the last years, several studies have shed light on the role of microRNAs in BTC, making them potentially attractive therapeutic targets and candidates as biomarkers. In this review, we will focus on the role of oncogenic and tumor suppressor microRNAs and their direct targets in BTC. Furthermore, we summarize and discuss data that evaluate the diagnostic power of deregulated microRNAs as possible future biomarkers for BTC.

MicroRNA networks in pulmonary arterial hypertension: share mechanisms with cancer?

PURPOSE OF REVIEW

Pulmonary arterial hypertension (PAH) is a rare disease with poor prognosis and no therapeutics. PAH is characterized by severe remodeling of precapillary pulmonary arteries, leading to increased vascular resistance, pulmonary hypertension compensatory right ventricular hypertrophy, then heart failure and death. PAH pathogenesis shares similarities with carcinogenesis such as excessive cell proliferation, apoptosis resistance, metabolic shifts, or phenotypic transition. Although PAH is not a cancer, comparison of analogous mechanisms between PAH and cancer led to the concept of a cancer-like disease to emerge. MicroRNAs (miRNAs) are small noncoding RNAs involved in the regulation of posttranscriptional gene expression. miRNA dysregulations have been reported as promoter of the development of various diseases including cancers.

RECENT FINDINGS

Recent studies revealed that miRNA dysregulations also occur in PAH pathogenesis. In PAH, different miRNAs have been implicated to be the main features of PAH pathophysiology (in pulmonary inflammation, vascular remodeling, angiogenesis, and right heart hypertrophy).

SUMMARY

The review summarizes the implication of miRNA dysregulation in PAH development and discusses the similarities and differences with those observed in cancers.

Melanoma Brain Metastasis: Mechanisms, Models, and Medicine

The development of brain metastases in patients with advanced stage melanoma is common, but the molecular mechanisms responsible for their development are poorly understood. Melanoma brain metastases cause significant morbidity and mortality and confer a poor prognosis; traditional therapies including whole brain radiation, stereotactic radiotherapy, or chemotherapy yield only modest increases in overall survival (OS) for these patients. While recently approved therapies have significantly improved OS in melanoma patients, only a small number of studies have investigated their efficacy in patients with brain metastases. Preliminary data suggest that some responses have been observed in intracranial lesions, which has sparked new clinical trials designed to evaluate the efficacy in melanoma patients with brain metastases. Simultaneously, recent advances in our understanding of the mechanisms of melanoma cell dissemination to the brain have revealed novel and potentially therapeutic targets. In this review, we provide an overview of newly discovered mechanisms of melanoma spread to the brain, discuss preclinical models that are being used to further our understanding of this deadly disease and provide an update of the current clinical trials for melanoma patients with brain metastases.

Possible tumor suppressive role of the miR-144/451 cluster in esophageal carcinoma as determined by principal component regression analysis

MicroRNA (miRNA) clusters are expressed universally across different types of organisms, and an accumulating number of studies have demonstrated that miRNA clusters function more efficiently compared with single miRNAs during the development of certain cancer types. miRNA clusters may have increased stability and reliability over individual miRNAs as diagnostic or therapeutic biomarkers. In the present study, the expression levels of mature miRNAs within the miR-144/451 cluster were examined using stem‑loop reverse transcription‑quantitative polymerase chain reaction in 102 patients pathologically diagnosed with esophageal carcinoma. Bioinformatics tools were used to identify a possible miRNA‑mediated network of the miR‑144/451 cluster. The expression levels of hsa‑miR‑451a, hsa‑miR‑144‑3p and hsa‑miR‑144‑5p in tumor tissues were significantly lower compared with those in adjacent non‑tumor tissues (P<0.05). Pearson correlation analysis demonstrated that the expression levels of individual miR‑144/451 cluster members were correlated with each other, except for the pair of hsa‑miR‑144‑3p and hsa‑miR‑4732‑3p. In particular, hsa‑miR‑144‑5p expression was highly associated with hsa-miR-4732‑5p and hsa-miR-451a expression levels, with correlation coefficients of 0.729 and 0.608, respectively. Furthermore, the low expression levels of hsa‑miR‑144‑3p [odds ratio (OR), 0.85; P<0.05] and hsa-miR-144-5p (OR, 0.84; P<0.05) were determined to be risk factors for esophageal carcinoma development. Kyoto Encyclopedia of Genes and Genomes pathway analysis demonstrated that miRNAs forming the miR‑144/451 cluster may cooperate to regulate the cell cycle. Therefore, the miR‑144/451 cluster may serve an important role in the progression of esophageal carcinoma and may be considered as a biomarker for the detection of esophageal carcinoma at an early stage.

Extracellular RNA in aging

Since the discovery of extracellular RNA (exRNA) in circulation and other bodily fluids, there has been considerable effort to catalog and assess whether exRNAs can be used as markers for health and disease. A variety of exRNA species have been identified including messenger RNA and noncoding RNA such as microRNA (miRNA), small nucleolar RNA, transfer RNA, and long noncoding RNA. Age-related changes in exRNA abundance have been observed, and it is likely that some of these transcripts play a role in aging. In this review, we summarize the current state of exRNA profiling in various body fluids and discuss age-related changes in exRNA abundance that have been identified in humans and other model organisms. miRNAs, in particular, are a major focus of current research and we will highlight and discuss the potential role that specific miRNAs might play in age-related phenotypes and disease. We will also review challenges facing this emerging field and various strategies that can be used for the validation and future use of exRNAs as markers of aging and age-related disease. WIREs RNA 2017, 8:e1385. doi: 10.1002/wrna.1385 For further resources related to this article, please visit the WIREs website.

Macrophage bone morphogenic protein receptor 2 depletion in idiopathic pulmonary fibrosis and Group III pulmonary hypertension

Idiopathic pulmonary fibrosis (IPF) is a lethal lung disease of unknown etiology. The development of pulmonary hypertension (PH) is considered the single most significant predictor of mortality in patients with chronic lung diseases. The processes that govern the progression and development of fibroproliferative and vascular lesions in IPF are not fully understood. Using human lung explant samples from patients with IPF with or without a diagnosis of PH as well as normal control tissue, we report reduced BMPR2 expression in patients with IPF or IPF+PH. These changes were consistent with dampened P-SMAD 1/5/8 and elevated P-SMAD 2/3, demonstrating reduced BMPR2 signaling and elevated TGF-β activity in IPF. In the bleomycin (BLM) model of lung fibrosis and PH, we also report decreased BMPR2 expression compared with control animals that correlated with vascular remodeling and PH. We show that genetic abrogation or pharmacological inhibition of interleukin-6 leads to diminished markers of fibrosis and PH consistent with elevated levels of BMPR2 and reduced levels of a collection of microRNAs (miRs) that are able to degrade BMPR2. We also demonstrate that isolated bone marrow-derived macrophages from BLM-exposed mice show reduced BMPR2 levels upon exposure with IL6 or the IL6+IL6R complex that are consistent with immunohistochemistry showing reduced BMPR2 in CD206 expressing macrophages from lung sections from IPF and IPF+PH patients. In conclusion, our data suggest that depletion of BMPR2 mediated by a collection of miRs induced by IL6 and subsequent STAT3 phosphorylation as a novel mechanism participating to fibroproliferative and vascular injuries in IPF.

MicroRNA-based screens for synthetic lethal interactions with c-Myc

microRNAs (miRs) are small, non-coding RNAs, which play crucial roles in the development and progression of human cancer. Given that miRs are stable, easy to synthetize and readily introduced into cells, they have been viewed as having potential therapeutic benefit in cancer. c-Myc (Myc) is one of the most commonly deregulated oncogenic transcription factors and has important roles in the pathogenesis of cancer, thus making it an important, albeit elusive therapeutic target. Here we review the miRs that have been identified as being both positive and negative targets for Myc and how these participate in the complex phenotypes that arise as a result of Myc-driven transformation. We also discussseveral recent reports of Myc-synthetic lethal interactions with miRs.These highlight the importance and complexity of miRs in Myc-mediated biological functions and the opportunities for Myc-driven human cancer therapies.

miR-17-92 plays an oncogenic role and conveys chemo-resistance to cisplatin in human prostate cancer cells

The mir-17-92 cluster consists of six mature miRNAs and is implicated in diverse human cancers by targeting mRNAs involved in distinct pathways that either promote or inhibit carcinogenesis. However, the molecular mechanism underlying the mir-17-92 cluster-mediated pro-tumorigenic or anti-tumorigenic effects has not been clearly elucidated in prostate cancer. In the present study, the role of the mir-17-92 cluster in diverse aspects of prostate cancer cells has been thoroughly investigated. Forced introduction of the mir-17-92 cluster into the androgen-independent DU145 prostate cancer cells evidently promoted cell growth due to disruption of the balance between cellular proliferation and apoptosis. Overexpression of the mir-17-92 cluster significantly improved the migration and invasion of the DU145 cells, attributed to the induction of integrin β-1. Notably, the mir-17-92 cluster conveyed chemo-resistance to cisplatin. We demonstrated that the mir-17-92 cluster suppressed the expression of inhibitor of the AKT signaling pathway and activated the AKT pathway subsequently, which played a central role in regulating cellular proliferation, apoptosis and chemo-resistance. Continuously activated ERK1/2 signaling also contributed importantly to these processes. The present study provides key evidence for crucial oncogenic role of the miR-17-92 cluster in prostate cancer cells. Further investigations are warranted to determine whether miR-17-92 cluster can be targeted for future treatment of human prostate cancer.

MicroRNAs in cholangiopathies: Potential diagnostic and therapeutic tools

Cholangiopathies are the group of diseases targeting the bile duct epithelial cells (i.e. cholangiocytes). These disorders arise from different etiologies and represent a current diagnostic, prognostic and therapeutic challenge. Different molecular mechanisms participate in the development and progression of each type of biliary disease. However, microRNA deregulation is a common central event occurring in all of them that plays a key role in their pathogenesis. MicroRNAs are highly stable small non-coding RNAs present in cells, extracellular microvesicles and biofluids, representing valuable diagnostic tools and potential targets for therapy. In the following sections, the most novel and significant discoveries in this field are summarized and their potential clinical value is highlighted.

HPV 16 E7 inhibits OSCC cell proliferation, invasion, and metastasis by upregulating the expression of miR-20a

The aim of this research was to study how HPV-16 E7 affects the proliferation, invasion, and metastasis of oral squamous cell carcinoma (OSCC) cells by upregulating the expression of miR-20a. A total of 60 OSCC patients were included in this study. SiRNA-198 was used to inhibit HPV-16 E7, and the constructed plasmid of HPV-16 E7 was transfected into Cal27 cells. Then, HPV-16 E7 protein was detected by Western blot and RT-PCR was performed to measure miR-20a expression in OSCC cells. Either HPV-16 E7 or the combination of HPV-16 E7 and miR-20a inhibitors was transfected into Cal27 cells separately. And then, the effect of miR-20a on OSCC cells proliferation was evaluated by CCK-8. Moreover, transwell assay and wound healing assay were used to assess the impact of miR-20a on OSCC cell invasion migration. MiR-20a was significantly higher in OSCC tissues compared with para-carcinoma tissues. RT-PCR results indicated that miR-20a was downregulated after silencing HPV-16 E7. By contrast, miR-20a was upregulated after the overexpression of HPV-16 E7. Upregulation of miR-20a by transfected plasmid HPV-16 E7 can significantly inhibit Cal27 cell proliferation, invasion, and migration. The expression of MiR-20a upregulated by HPV-16 E7 inhibits the proliferation, invasion, and migration of OSCC cells.