miR-9 Acts as an OncomiR in Prostate Cancer through Multiple Pathways That Drive Tumour Progression and Metastasis

The role of microRNA-9 in ovarian and cervical cancers: An updated overview

Ovarian and cervical cancers are the two most frequent kind of gynaecological cancers (GCs). In spite of advances in prevention, screening and treatment, cervical cancer still leads to an increased morbidity and mortality worldwide. Ovarian cancer is often detected at a late stage, which significantly reduces the effectiveness of available treatments. Therefore, novel methods are desperately needed to improve the clinical care of GC patients. MicroRNAs, also known as short noncoding RNAs (miRNAs/miRs), are a diverse group of RNAs with a length of 22 nucleotides. These typically cause translational repression and mRNA degradation by interacting with target mRNAs' 3' untranslated region (3'-UTR), together with other regions and gene promoters. Under certain conditions, they are also able to activate translation or regulate transcription. It has been demonstrated that miRNAs are crucial to several biological processes leading to tumorigenesis, including GCs. Recent research has shown that miR-9 affects carcinogenesis. In this review, we will provide an overview of current research on the potential utility of miR-9 in the diagnosis, prognosis, and therapy of ovarian and cervical malignancies.

Dysregulated expression of the suppressors of cytokine signaling (SOCS) contributes to the development of prostate cancer

Different types of cytokines, growth factors, or hormones present within the tumor microenvironment that can activate the JAK-STAT signaling pathway by binding to their specific cell surface receptors. The constitutive activation of the JAK-STAT pathway can promote uncontrolled cell proliferation and prevent apoptosis contributing to tumor development. Activation of the JAK-STAT pathway is controlled by several regulatory molecules, particularly the suppressor of cytokine signaling (SOCS) family consisting of eight members, which include SOCS1-SOCS7 and the cytokine-inducible SH2-containing (CIS) proteins. In prostate cancer cells, the irregular expression of the SOCS1-SOCS3, SOCS5-SOCS7 as well as CIS can similarly and differentially result in the initiation of various cellular signaling pathways (in particular JAK-STAT3, MAPK, ERK) that promote cell proliferation, migration, invasion and viability; cell cycle progression; epithelial-mesenchymal transition; angiogenesis; resistance to therapy; immune evasion; and chronic inflammation within the tumor microenvironment which lead to tumor progression, metastasis and poor prognosis. Epigenetic modifications, mainly due to DNA methylation, microRNAs, pro-inflammatory cytokines, growth factors and androgens can influence the expression of the SOCS molecules in prostate cancer cells. Using strategies to modulate, restore or enhance the expression of SOCS proteins, may help overcome treatment resistance and improve the efficacy of existing therapies. In this review, we provide a comprehensive explanation regarding SOCS dysregulation in prostate cancer to provide insights into the mechanisms underlying the dysregulation of SOCS proteins. This knowledge may pave the way for the development of novel therapeutic strategies to manage prostate cancer by restoring and modulating the expression of SOCS molecules.

Resistin stimulates PC-3 prostate cancer cell growth through stimulation of SOCS3 and SOCS5 genes

Resistin and suppressors of cytokine signaling (SOCSs) have been reported to regulate prostate cancer (PCa) cell proliferation and survival, respectively. Whether any of the SOCS molecules mediate the mitogenic effect of resistin on PCa cells is unknown. Using PC-3 human PCa cells, we found that resistin upregulates the expression of SOCS3 and SOCS5 mRNA, but not SOCS7 mRNA, in a dose- and time-dependent manner. The resistin-induced increases in SOCS3 and SOCS5 expression and cell proliferation were prevented by pretreatment with specific inhibitors of the TLR4, ERK, p38 MAPK, JNK, PI3K, and JAK2 proteins. However, pretreatment with a TLR2 inhibitor had no effect on resistin-mediated SOCS3 and SOCS5 expression. In addition, the effects of resistin on SOCS3, SOCS5, and SOCS7 mRNA levels were cell type-specific. Overexpression of either SOCS3 or SOCS5 enhanced further resistin-stimulated growth of PC-3 cells, whereas silencing SOCS3 or SOCS5 antagonized resistin-increased cell growth. Further PCa tissue analysis demonstrated higher levels of RETN, TLR4, SOCS3, and SOCS5 mRNAs in cancer tissues than benign prostate hyperplasia and indicated positive correlations among RETN, TLR4, and SOCS5. These data suggest that SOCS5, TLR4, and, to a lesser extent, SOCS3 can mediate the mitogenic effect of resistin on PC-3 PCa cells.

Analytical and therapeutic profiles of DNA methylation alterations in cancer; an overview of changes in chromatin arrangement and alterations in histone surfaces

DNA methylation is the most important epigenetic element that activates the inhibition of gene transcription and is included in the pathogenesis of all types of malignancies. Remarkably, the effectors of DNA methylation are DNMTs (DNA methyltransferases) that catalyze de novo or keep methylation of hemimethylated DNA after the DNA replication process. DNA methylation structures in cancer are altered, with three procedures by which DNA methylation helps cancer development which are including direct mutagenesis, hypomethylation of the cancer genome, and also focal hypermethylation of the promoters of TSGs (tumor suppressor genes). Conspicuously, DNA methylation, nucleosome remodeling, RNA-mediated targeting, and histone modification balance modulate many biological activities that are essential and indispensable to the genesis of cancer and also can impact many epigenetic changes including DNA methylation and histone modifications as well as adjusting of non-coding miRNAs expression in prevention and treatment of many cancers. Epigenetics points to heritable modifications in gene expression that do not comprise alterations in the DNA sequence. The nucleosome is the basic unit of chromatin, consisting of 147 base pairs (bp) of DNA bound around a histone octamer comprised of one H3/H4 tetramer and two H2A/H2B dimers. DNA methylation is preferentially distributed over nucleosome regions and is less increased over flanking nucleosome-depleted DNA, implying a connection between nucleosome positioning and DNA methylation. In carcinogenesis, aberrations in the epigenome may also include in the progression of drug resistance. In this report, we report the rudimentary notes behind these epigenetic signaling pathways and emphasize the proofs recommending that their misregulation can conclude in cancer. These findings in conjunction with the promising preclinical and clinical consequences observed with epigenetic drugs against chromatin regulators, confirm the important role of epigenetics in cancer therapy.

MicroRNAs in Tumor Endothelial Cells: Regulation, Function and Therapeutic Applications

Tumor endothelial cells (TECs) are key stromal components of the tumor microenvironment, and are essential for tumor angiogenesis, growth and metastasis. Accumulating evidence has shown that small single-stranded non-coding microRNAs (miRNAs) act as powerful endogenous regulators of TEC function and blood vessel formation. This systematic review provides an up-to-date overview of these endothelial miRNAs. Their expression is mainly regulated by hypoxia, pro-angiogenic factors, gap junctions and extracellular vesicles, as well as long non-coding RNAs and circular RNAs. In preclinical studies, they have been shown to modulate diverse fundamental angiogenesis-related signaling pathways and proteins, including the vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR) pathway; the rat sarcoma virus (Ras)/rapidly accelerated fibrosarcoma (Raf)/mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway; the phosphoinositide 3-kinase (PI3K)/AKT pathway; and the transforming growth factor (TGF)-β/TGF-β receptor (TGFBR) pathway, as well as krüppel-like factors (KLFs), suppressor of cytokine signaling (SOCS) and metalloproteinases (MMPs). Accordingly, endothelial miRNAs represent promising targets for future anti-angiogenic cancer therapy. To achieve this, it will be necessary to further unravel the regulatory and functional networks of endothelial miRNAs and to develop safe and efficient TEC-specific miRNA delivery technologies.

Tumor cells-derived exosomal circVCP promoted the progression of colorectal cancer by regulating macrophage M1/M2 polarization

BACKGROUND

Colorectal cancer (CRC) is among the most frequent tumors of the digestive tract and the second leading cause of cancer death worldwide. Tumor-associated macrophages (TAMs) are one of the most critical immune cells in the tumor microenvironment, which closely interact with tumor cells to promote tumor incidence and progression. However, the precise mechanism of action between CRC cells and TAMs polarization is still being investigated.

METHODS

Transmission electronic microscopy (TEM), NanoSight and western blotting were used to characterize exosomes (Exo) isolated from the culture medium of CRC cells. The cellular uptake and internalization of Exo were detected by confocal laser scanning microscopy. M1/ M2 phenotype markers expression were examined by ELISA and flow cytometry. Cell migration, invasion and proliferation were determined by transwell and CCK-8 assay, respectively. A xenograft tumor model was established to explore the role of circVCP in vivo. The target genes of circVCP or miR-9-5p were predicted by StarBase2.0. The target association among miR-9-5p and circVCP or NRP1 was confirmed using the luciferase assay and RNA-pull down assay.

RESULTS

circVCP was highly accumulated in exosomes derived from plasma of CRC patients and CRC cells. Additionally, exosomal circVCP derived from CRC cells promoted cell proliferation, migration and invasion by regulating the miR-9-5p/NRP1 axis, and induced macrophage M2 polarization and inhibited macrophage M1 polarization.

CONCLUSIONS

Over-expressed exosomal circVCP promoted the progression of CRC by regulating macrophage M1/M2 polarization through miR-9-5p/NRP1 axis. CircVCP may be a diagnostic biomarker and potential target for CRC therapy.

Effects of miR-9-5p on the migration, invasion and epithelial-mesenchymal transition process in cervical squamous cell carcinoma

OBJECTIVES

Cervical squamous cell carcinoma is the most common cancer in female reproductive system. This study aims to explore the effect of microRNA-9-5p (miR-9-5p) on the migration, invasion, and epithelial-mesenchymal transition (EMT) process of cervical squamous cells.

METHODS

Bioinformatics were used to predict the miRNAs that could bind to E-cadherin (E-cad). The Cancer Genome Atlas (TCGA) database was used to analyze and extract significantly differentially expressed miRNAs from part of cervical squamous cell carcinoma tissues and normal cervical tissues, and miR-9-5p was selected as the main research target. The translated regions (UTR) of wild-type E-cad (E-cad-WT 3'-UTR) or the 3'-UTR of mutant E-cad (E-Cad-MUT 3'-UTR) was transfected with miR-9-5p mimic normal control (NC), and miR-9-5p mimic was co-transfected human embryonic kidney cells (293T). The relationship between miR-9-5p and E-cad was detected by double luciferase assay. The expression of miR-9-5p in normal cervical epithelial cell lines (H8) and cervical squamous cell lines (C33A, siha, caski and Me180) were detected by quantitative real-time PCR. Then, the experiments were divided into groups as follows: a block control group, an overexpression control group (mimic-NC group), a miR-95p overexpression group (mimic group), an inhibitory expression control group (inhibitor-NC group), and a miR-9-5p inhibitory expression group (inhibitor group). The changes of migration ability were detected by scratch assay. Transwell invasion assay was used to analyze the changes of invasion ability, and the mRNA and protein changes of E-cad and vimentin were detected by quantitative real-time PCR and Western blotting.

RESULTS

MiR-9-5p had a targeting binding relationship with E-cad. Compared with the normal cervical tissue H8 cell line, the miR-9-5p was highly expressed in cervical cancer cell lines (C33A, siha, caski and Me180) (all P<0.05). The luciferase activity of E-cad-MUT was increased compared with that of E-cad-WT in miR-9-5p mimic cells (P<0.05). Compared with the blank control group, the protein and mRNA expressions of E-cad were decreased in the miR-9-5p mimic group (both P<0.05), which were increased in the miR-9-5p inhibitor group (both P<0.05). Compared with H8 cell line, the miR-9-5p was highly expressed in the cervical squamous cell lines (all P<0.05). Compared with the mimic-NC group, the distance of wound healing, the number of caski and Me180 cells invaded below the membrane, and the mRNA and protein expressions of vimentin were all increased in the miR-9-5p mimic group (all P<0.05), while the mRNA and protein of E-cad were decreased (both P<0.05). Compared with the inhibitor-NC group, the distance of wound healing, the number of caski and Me180 cells invading the membrane, and the mRNA and protein expressions of vimentin were decreased in the miR-9-5p inhibitor group (all P<0.05), but the mRNA and protein expressions of E-cad were increased (both P<0.05).

CONCLUSIONS

The miR-9-5p is highly expressed in cervical squamous cell carcinoma, which can increase the migration and invasion ability, and promote the EMT process of cancer cells.

Integrative Analysis of Bulk RNA-Seq and Single-Cell RNA-Seq Unveils the Characteristics of the Immune Microenvironment and Prognosis Signature in Prostate Cancer

The immune microenvironment is a culmination of the collaborative effort of immune cells and is important in cancer development. The underlying mechanisms of the tumor immune microenvironment in regulating prostate cancer (PRAD) are unclear. In the current study, 144 natural killer cell-related genes were identified using differential expression, single-sample gene set enrichment analysis, and weighted gene coexpression network analysis. Furthermore, VCL, ACTA2, MYL9, MYLK, MYH11, TPM1, ACTG2, TAGLN, and FLNC were selected as hub genes via the protein-protein interaction network. Based on the expression patterns of the hub genes, endothelial, epithelial, and tissue stem cells were identified as key cell subpopulations, which could regulate PRAD via immune response, extracellular signaling, and protein formation. Moreover, 27 genes were identified as prognostic signatures and used to construct the risk score model. Receiver operating characteristic curves revealed the good performance of the risk score model in both the training and testing datasets. Different chemotherapeutic responses were observed between the low- and high-risk groups. Additionally, a nomogram based on the risk score and other clinical features was established to predict the 1-, 3-, and 5-year progression-free interval of patients with PRAD. This study provides novel insights into the molecular mechanisms of the immune microenvironment and its role in the pathogenesis of PARD. The identification of key cell subpopulations has a potential therapeutic and prognostic use in PRAD.

Association of miR-9-5p and NFIC in the progression of gastric cancer

BACKGROUND

Gastric cancer is the most common malignant neoplasm of digestive system. Herein, we aim to detect the expression of nuclear factor I C (NFIC) in gastric cancer cells, and to explore the effect and mechanism of its expression on the development of gastric cancer.

METHODS

qPCR and Western blot assays were carried out to detect NFIC expression. Then, BGC-823 and SGC-7901 cell lines were selected to perform the following functional experiments. The function of NFIC on gastric cancer cells was analyzed by biological experiments. The associations between miR-9-5p and NFIC were searched on the bioinformatics website and identified by dual luciferase assay. The effects of miR-9-5p and NFIC on cells were verified by co-transfection experiments. The related genes expression was examined by Western blot.

RESULTS

A marked augmentation of NFIC was observed in gastric cancer cells. Knockdown of NFIC significantly inhibited the viability, colony formation, invasion, and migration of gastric cancer cells. Overexpression of miR-9-5p obviously suppressed the viability, colony formation, invasion, and migration of gastric cancer cells, and this phenomenon was aggravated by si-NFIC. Additionally, the expression levels of PCNA, vimentin, and Snail were obviously decreased after miR-9-5p mimic or/and si-NFIC treatment.

CONCLUSIONS

These results suggested that NFIC was highly expressed in gastric cancer cells, and knockdown of NFIC suppressed the growth and mobility of gastric cancer cells; miR-9-5p was identified as an upstream regulator of NFIC and suppressed the malignant behaviors of gastric cancer cells by targeting NFIC through affecting PCNA, vimentin, and Snail expression.

Loss of microRNA-135b Enhances Bone Metastasis in Prostate Cancer and Predicts Aggressiveness in Human Prostate Samples

About 70% of advanced-stage prostate cancer (PCa) patients will experience bone metastasis, which severely affects patients' quality of life and progresses to lethal PCa in most cases. Hence, understanding the molecular heterogeneity of PCa cell populations and the signaling pathways associated with bone tropism is crucial. For this purpose, we generated an animal model with high penetrance to metastasize to bone using an intracardiac percutaneous injection of PC3 cells to identify PCa metastasis-promoting factors. Using genomic high-throughput analysis we identified a miRNA signature involved in bone metastasis that also presents potential as a biomarker of PCa progression in human samples. In particular, the downregulation of miR-135b favored the incidence of bone metastases by significantly increasing PCa cells' migratory capacity. Moreover, the PLAG1, JAKMIP2, PDGFA, and VTI1b target genes were identified as potential mediators of miR-135b's role in the dissemination to bone. In this study, we provide a genomic signature involved in PCa bone growth, contributing to a better understanding of the mechanisms responsible for this process. In the future, our results could ultimately translate into promising new therapeutic targets for the treatment of lethal PCa.

tsRFun: a comprehensive platform for decoding human tsRNA expression, functions and prognostic value by high-throughput small RNA-Seq and CLIP-Seq data

tRNA-derived small RNA (tsRNA), a novel type of regulatory small noncoding RNA, plays an important role in physiological and pathological processes. However, the understanding of the functional mechanism of tsRNAs in cells and their role in the occurrence and development of diseases is limited. Here, we integrated multiomics data such as transcriptome, epitranscriptome, and targetome data, and developed novel computer tools to establish tsRFun, a comprehensive platform to facilitate tsRNA research (http://rna.sysu.edu.cn/tsRFun/ or http://biomed.nscc-gz.cn/DB/tsRFun/). tsRFun evaluated tsRNA expression profiles and the prognostic value of tsRNAs across 32 types of cancers, identified tsRNA target molecules utilizing high-throughput CLASH/CLEAR or CLIP sequencing data, and constructed the interaction networks among tsRNAs, microRNAs, and mRNAs. In addition to its data presentation capabilities, tsRFun offers multiple real-time online tools for tsRNA identification, target prediction, and functional enrichment analysis. In summary, tsRFun provides a valuable data resource and multiple analysis tools for tsRNA investigation.

MicroRNA-9 as a paradoxical but critical regulator of cancer metastasis: Implications in personalized medicine

Metastasis, is a development of secondary tumor growths at a distance from the primary site, and closely related to poor prognosis and mortality. However, there is still no effective treatment for metastatic cancer. Therefore, there is an urgent need to find an effective therapy for cancer metastasis. Plenty of evidence indicates that miR-9 can function as a promoter or suppressor in cancer metastasis and coordinate multistep of metastatic process. In this review, we summarize the different roles of miR-9 with the corresponding molecular mechanisms in metastasis of twelve common cancers and the multiple mechanisms underlying miR-9-mediated regulation of metastasis, benefiting the further research of miR-9 and metastasis, and hoping to bridge it with clinical applications.

Role of Metastasis-Related microRNAs in Prostate Cancer Progression and Treatment

Simple Summary

In this review article we summarize the current literature on the pro- and anti-metastatic roles of distinct microRNAs in prostate cancer with a particular focus on their impact on invasion, migration and epithelial-to-mesenchymal transition. Moreover, we give a brief overview on how this knowledge developed so far into novel therapeutic approaches to target metastatic prostate cancer.

Abstract

Prostate cancer (PCa) is one of the most prevalent cancer types in males and the consequences of its distant metastatic deposits are the leading cause of PCa mortality. Therefore, identifying the causes and molecular mechanisms of hematogenous metastasis formation is of considerable clinical importance for the future development of improved therapeutic approaches. MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression at the post-transcriptional level by targeting messenger RNAs. Numerous studies have identified miRNAs as promotors or inhibitors of metastasis and revealed, in part, their targeting pathways in PCa. Because miRNAs are remarkably stable and can be detected in both tissue and body fluid, its potential as specific biomarkers for metastasis and therapeutic response is also currently under preclinical evaluation. In the present review, we focus on miRNAs that are supposed to initiate or suppress metastasis by targeting several key mRNAs in PCa. Metastasis-suppressing miRNAs include miR-33a-5p, miR-34, miR-132 and miR-212, miR-145, the miR-200 family (incl. miR-141-3p), miR-204-5p, miR-532-3p, miR-335, miR-543, miR-505-3p, miR 19a 3p, miR-802, miR-940, and miR-3622a. Metastasis-promoting RNAs, such as miR-9, miR-181a, miR-210-3, miR-454, miR-671-5p, have been shown to increase the metastatic potential of PCa cells. Other metastasis-related miRNAs with conflicting reports in the literature are also discussed (miR-21 and miR-186). Finally, we summarize the recent developments of miRNA-based therapeutic approaches, as well as current limitations in PCa. Taken together, the metastasis-controlling miRNAs provide the potential to be integrated in the strategy of diagnosis, prognosis, and treatment of metastatic PCa. Nevertheless, there is still a lack of consistency between certain miRNA signatures and reproducibility, which impedes clinical implementation.

Methylation-associated silencing of miR-9-1 promotes nasopharyngeal carcinoma progression and glycolysis via HK2

Characteristically, cancer cells metabolize glucose through aerobic glycolysis, known as the Warburg effect. Accumulating evidence suggest that during cancer formation, microRNAs (miRNAs) could regulate such metabolic reprogramming. In the present study, miR‐9‐1 was identified as significantly hypermethylated in nasopharyngeal carcinoma (NPC) cell lines and clinical tissues. Ectopic expression of miR‐9‐1 inhibited NPC cell growth and glycolytic metabolism, including reduced glycolysis, by reducing lactate production, glucose uptake, cellular glucose‐6‐phosphate levels, and ATP generation in vitro and tumor proliferation in vivo. HK2 (encoding hexokinase 2) was identified as a direct target of miR‐9‐1 using luciferase reporter assays and Western blotting. In NPC cells, hypermethylation regulates miR‐9‐1 expression and inhibits HK2 translation by directly targeting its 3' untranslated region. MiR‐9‐1 overexpression markedly reduced HK2 protein levels. Restoration of HK2 expression attenuated the inhibitory effect of miR‐9‐1 on NPC cell proliferation and glycolysis. Fluorescence in situ hybridization results indicated that miR‐9‐1 expression was an independent prognostic factor in NPC. Our findings revealed the role of the miR‐9‐1/HK2 axis in the metabolic reprogramming of NPC, providing a potential therapeutic strategy for NPC.

Cell Plasticity and Prostate Cancer: The Role of Epithelial-Mesenchymal Transition in Tumor Progression, Invasion, Metastasis and Cancer Therapy Resistance

Simple Summary

Although epithelial-to-mesenchymal transition (EMT) is a well-known cellular process involved during normal embryogenesis and wound healing, it also has a dark side; it is a complex process that provides tumor cells with a more aggressive phenotype, facilitating tumor metastasis and even resistance to therapy. This review focuses on the key pathways of EMT in the pathogenesis of prostate cancer and the development of metastases and evasion of currently available treatments.

Abstract

Prostate cancer, the second most common malignancy in men, is characterized by high heterogeneity that poses several therapeutic challenges. Epithelial–mesenchymal transition (EMT) is a dynamic, reversible cellular process which is essential in normal embryonic morphogenesis and wound healing. However, the cellular changes that are induced by EMT suggest that it may also play a central role in tumor progression, invasion, metastasis, and resistance to current therapeutic options. These changes include enhanced motility and loss of cell–cell adhesion that form a more aggressive cellular phenotype. Moreover, the reverse process (MET) is a necessary element of the metastatic tumor process. It is highly probable that this cell plasticity reflects a hybrid state between epithelial and mesenchymal status. In this review, we describe the underlying key mechanisms of the EMT-induced phenotype modulation that contribute to prostate tumor aggressiveness and cancer therapy resistance, in an effort to provide a framework of this complex cellular process.

The LINC01119-SOCS5 axis as a critical theranostic in triple-negative breast cancer

The development of triple-negative breast cancer (TNBC) is critically regulated by certain tumor-microenvironment-associated cells called mesenchymal stem/stromal cells (MSCs), which we and others have shown promote TNBC progression by activating pro-malignant signaling in neighboring cancer cells. Characterization of these cascades would better our understanding of TNBC biology and bring about therapeutics that eliminate the morbidity and mortality associated with advanced disease. Here, we focused on the emerging class of RNAs called long non-coding RNAs or lncRNAs and utilized a MSC-supported TNBC progression model to identify specific family members of functional relevance to TNBC pathogenesis. Indeed, although some have been described to play functional roles in TNBC, activities of lncRNAs as mediators of tumor-microenvironment-driven TNBC development remain to be fully explored. We report that MSCs stimulate robust expression of LINC01119 in TNBC cells, which in turn induces suppressor of cytokine signaling 5 (SOCS5), leading to accelerated cancer cell growth and tumorigenesis. We show that LINC01119 and SOCS5 exhibit tight correlation across multiple breast cancer gene sets and that they are highly enriched in TNBC patient cohorts. Importantly, we present evidence that the LINC01119-SOCS5 axis represents a powerful prognostic indicator of adverse outcomes in TNBC patients, and demonstrate that its repression severely impairs cancer cell growth. Altogether, our findings identify LINC01119 as a major driver of TNBC development and delineate critical non-coding RNA theranostics of potential translational utility in the management of advanced TNBC, a class of tumors in most need of effective and targeted therapy.

NUMB suppression by miR-9-5P enhances CD44+ prostate cancer stem cell growth and metastasis

Experimental and clinical studies over the past two decades have provided overwhelming evidence that human cancers, including prostate cancer (PCa), harbor cancer stem cells (CSCs) that sustain tumor growth, drive tumor progression and mediate therapy resistance and tumor relapse. Recent studies have also implicated NUMB as a PCa suppressor and an inhibitor of PCa stem cells (PCSCs); however, exactly how NUMB functions in these contexts remains unclear. Here, by employing bioinformatics analysis and luciferase assays and by conducting rescue experiments, we first show that NUMB is directly targeted by microRNA-9-5p (miR-9-5p), an oncogenic miR associated with poor prognosis in many malignancies. We further show that miR-9-5p levels are inversely correlated with NUMB expression in CD44+ PCSCs. miR-9-5p reduced NUMB expression and inhibited numerous PCSC properties including proliferation, migration, invasion as well as self-renewal. Strikingly, overexpression of NUMB in CD44+ PCSCs overcame all of the above PCSC properties enforced by miR-9-5p. Taken together, our results suggest that inhibiting the expression of the oncomiR miR-9-5p and overexpressing NUMB may represent novel therapeutic strategies to target PCSCs and PCa metastasis.

miRNAs as Therapeutic Tools and Biomarkers for Prostate Cancer

Prostate cancer (PCa) is the fifth cause of tumor-related deaths in man worldwide. Despite the considerable improvement in the clinical management of PCa, several limitations emerged both in the screening for early diagnosis and in the medical treatment. The use of prostate-specific antigen (PSA)-based screening resulted in patients' overtreatment and the standard therapy of patients suffering from locally advanced/metastatic tumors (e.g., radical prostatectomy, radiotherapy, and androgen deprivation therapy) showed time-limited efficacy with patients undergoing progression toward the lethal metastatic castration-resistant PCa (mCRPC). Although valuable alternative therapeutic options have been recently proposed (e.g., docetaxel, cabazitaxel, abiraterone, enzalutamide, and sipuleucel-T), mCRPC remains incurable. Based on this background, there is an urgent need to identify new and more accurate prostate-specific biomarkers for PCa diagnosis and prognosis and to develop innovative medical approaches to counteract mCRPC. In this context, microRNA (miRNAs) emerged as potential biomarkers in prostate tissues and biological fluids and appeared to be promising therapeutic targets/tools for cancer therapy. Here we overview the recent literature and summarize the achievements of using miRNAs as biomarkers and therapeutic targets/tools for fighting PCa.

Long non-coding RNA HCG11 sponging miR-522-3p inhibits the tumorigenesis of non-small cell lung cancer by upregulating SOCS5

BACKGROUND

Numerous studies have shown that long non-coding RNA (lncRNA) is involved in various human diseases including non-small cell lung cancer (NSCLC). The aim of this study was to explore the potential role of lncRNA HCG11 in the pathogenesis of NSCLC.

METHODS

The mRNA expression of HCG11, miR-522-3p and SOCS5 was detected by RT-qPCR. The regulatory mechanism of lncRNA HCG11 was investigated by CCK-8, transwell and dual luciferase reporter assays.

RESULTS

Downregulation of lncRNA HCG11 and upregulation of miR-522-3p were found in NSCLC tissues and cells, and abnormal expressions of lncRNA HCG11 and miR-522-3p were related to adverse clinical outcomes of NSCLC patients. LncRNA HCG11 acted as a molecular sponge for miR-522-3p. Functionally, lncRNA HCG11 inhibited cell viability, migration and invasion in NSCLC by downregulating miR-522-3p. Further, miR-522-3p directly targeted SOCS5. lncRNA HCG11 could positively regulate SOCS5 expression in NSCLC. In addition, HCG11 downregulation or miR-522-3p overexpression abolished the inhibitory effect of SOCS5 on cell viability, migration and invasion in NSCLC.

CONCLUSIONS

LncRNA HCG11 inhibits cell viability, migration and invasion in NSCLC by functioning as a ceRNA of miR-522-3p to upregulate SOCS5.

Human mesenchymal stromal cells and derived extracellular vesicles: Translational strategies to increase their proangiogenic potential for the treatment of cardiovascular disease

Mesenchymal stromal cells (MSCs) offer great potential for the treatment of cardiovascular diseases (CVDs) such as myocardial infarction and heart failure. Studies have revealed that the efficacy of MSCs is mainly attributed to their capacity to secrete numerous trophic factors that promote angiogenesis, inhibit apoptosis, and modulate the immune response. There is growing evidence that MSC‐derived extracellular vesicles (EVs) containing a cargo of lipids, proteins, metabolites, and RNAs play a key role in this paracrine mechanism. In particular, encapsulated microRNAs have been identified as important positive regulators of angiogenesis in pathological settings of insufficient blood supply to the heart, thus opening a new path for the treatment of CVD. In the present review, we discuss the current knowledge related to the proangiogenic potential of MSCs and MSC‐derived EVs as well as methods to enhance their biological activities for improved cardiac tissue repair. Increasing our understanding of mechanisms supporting angiogenesis will help optimize future approaches to CVD intervention.

Xenograft-derived mRNA/miR and protein interaction networks of systemic dissemination in human prostate cancer

BACKGROUND

Distant metastasis formation is the major clinical problem in prostate cancer (PCa) and the underlying mechanisms remain poorly understood. Our aim was to identify novel molecules that functionally contribute to human PCa systemic dissemination based on unbiased approaches.

METHODS

We compared mRNA, microRNA (miR) and protein expression levels in established human PCa xenograft tumours with high (PC-3), moderate (VCaP) or weak (DU-145) spontaneous micrometastatic potential. By focussing on those mRNAs, miRs and proteins that were differentially regulated among the xenograft groups and known to interact with each other we constructed dissemination-related mRNA/miR and protein/miR networks. Next, we clinically and functionally validated our findings.

RESULTS

Besides known determinants of PCa progression and/or metastasis, our interaction networks include several novel candidates. We observed a clear role of epithelial-to-mesenchymal transition (EMT) pathways for PCa dissemination, which was additionally confirmed by an independent human PCa model (ARCAP-E/-M). Two converging nodes, CD46 (decreasing with metastatic potential) and DDX21 (increasing with metastatic potential), were used to test the clinical relevance of the networks. Intriguingly, both network nodes consistently added prognostic information for patients with PCa whereas CD46 loss predicted poor outcome independent of established parameters. Accordingly, depletion of CD46 in weakly metastatic PCa cells induced EMT-like properties in vitro and spontaneous micrometastasis formation in vivo.

CONCLUSIONS

The clinical and functional relevance of the dissemination-related interaction networks shown here could be successfully validated by proof-of-principle experiments. Therefore, we suggest a direct pro-metastatic, clinically relevant role for the multiple novel candidates included in this study; these should be further exploited by future studies.

Detection and Prognosis of Prostate Cancer Using Blood-Based Biomarkers

Prostate cancer (PCa) is second only to lung cancer as a cause of death. Clinical assessment of patients and treatment efficiency therefore depend on the disease being diagnosed as early as possible. However, due to issues regarding the use of prostate-specific antigen (PSA) for screening purposes, PCa management is among the most contentious of healthcare matters. PSA screening is problematic primarily because of diagnosis difficulties and the high rate of false-positive biopsies. Novel PCa biomarkers, such as the Prostate Health Index (PHI) and the 4Kscore, have been proposed in recent times to improve PSA prediction accuracy and have shown higher performance by preventing redundant biopsies. The 4Kscore also shows high precision in determining the risk of developing high-grade PCa, whereas elevated PHI levels suggest that the tumor is aggressive. Some evidence also supports the effectiveness of miRNAs as biomarkers for distinguishing PCa from benign prostatic hyperplasia and for assessing the aggressiveness of the disease. A number of miRNAs that possibly act as tumor inhibitors or oncogenes are impaired in PCa. These new biomarkers are comprehensively reviewed in the present study in terms of their potential use in diagnosing and treating PCa.

The A818-6 system as an in-vitro model for studying the role of the transportome in pancreatic cancer

Background

The human pancreatic cancer cell line A818–6 can be grown in vitro either as a highly malignant, undifferentiated monolayer (ML) or as three-dimensional (3D) single layer hollow spheres (HS) simulating a benign, highly differentiated, duct-like pancreatic epithelial structure. This characteristic allowing A818–6 cells to switch from one phenotype to another makes these cells a unique system to characterize the cellular and molecular modifications during differentiation on one hand and malignant transformation on the other hand. Ion channels and transport proteins (transportome) have been implicated in malignant transformation. Therefore, the current study aimed to analyse the transportome gene expression profile in the A818–6 cells growing as a monolayer or as hollow spheres.

Methods & Results

The study identified the differentially expressed transportome genes in both cellular states of A818–6 using Agilent and Nanostring arrays and some targets were validated via immunoblotting. Additionally, these results were compared to a tissue Affymetrix microarray analysis of pancreatic adenocarcinoma patients’ tissues. The overall transcriptional profile of the ML and HS cells confirmed the formerly described mesenchymal features of ML and epithelial nature of HS which was further verified via high expression of E-cadherin and low expression of vimentin found in HS in comparison to ML. Among the predicted features between HS and ML was the involvement of miRNA-9 in this switch. Importantly, the bioinformatics analysis also revealed substantial number (n = 126) of altered transportome genes. Interestingly, three genes upregulated in PDAC tissue samples (GJB2, GJB5 and SLC38A6) were found to be also upregulated in ML and 3 down-regulated transportome genes (KCNQ1, TRPV6 and SLC4A) were also reduced in ML.

Conclusion

This reversible HS/ML in vitro system might help in understanding the pathophysiological impact of the transportome in the dedifferentiation process in pancreatic carcinogenesis. Furthermore, the HS/ML model represents a novel system for studying the role of the transportome during the switch from a more benign, differentiated (HS) to a highly malignant, undifferentiated (ML) phenotype.

The miRNAs Role in Melanoma and in Its Resistance to Therapy

Melanoma is the less common but the most malignant skin cancer. Since the survival rate of melanoma metastasis is about 10–15%, many different studies have been carried out in order to find a more effective treatment. Although the development of target-based therapies and immunotherapeutic strategies has improved chances for patient survival, melanoma treatment still remains a big challenge for oncologists. Here, we collect recent data about the emerging role of melanoma-associated microRNAs (miRNAs) currently available treatments, and their involvement in drug resistance. We also reviewed miRNAs as prognostic factors, because of their chemical stability and resistance to RNase activity, in melanoma progression. Moreover, despite miRNAs being considered small conserved regulators with the limitation of target specificity, we outline the dual role of melanoma-associated miRNAs, as oncogenic and/or tumor suppressive factors, compared to other tumors.

miR-9-5p Exerts a Dual Role in Cervical Cancer and Targets Transcription Factor TWIST1

Squamous cell carcinoma (SCC) and adenocarcinoma (AC) represent the major cervical cancer histotypes. Both histotypes are caused by infection with high-risk HPV (hrHPV) and are associated with deregulated microRNA expression. Histotype-dependent expression has been observed for miR-9-5p, showing increased expression in SCC and low expression in AC. Here, we studied the regulation and functionality of miR-9-5p in cervical SCCs and ACs using cervical tissue samples and hrHPV-containing cell lines. Expression and methylation analysis of cervical tissues revealed that low levels of miR-9-5p in ACs are linked to methylation of its precursor genes, particularly miR-9-1. Stratification of tissue samples and hrHPV-containing cell lines suggested that miR-9-5p depends on both histotype and hrHPV type, with higher expression in SCCs and HPV16-positive cells. MiR-9-5p promoted cell viability and anchorage independence in cervical cancer cell lines SiHa (SCC, HPV16) and CaSki (metastasized SCC, HPV16), while it played a tumor suppressive role in HeLa (AC, HPV18). TWIST1, a transcription factor involved in epithelial-to-mesenchymal transition (EMT), was established as a novel miR-9-5p target. Our results show that miR-9-5p plays a dual role in cervical cancer in a histotype- and hrHPV type-dependent manner. MiR-9-5p mediated silencing of TWIST1 suggests two distinct mechanisms towards EMT in cervical cancer.

Assessment by miRNA microarray of an autologous cancer antigen-pulsed adoptive immune ensemble cell therapy (AC-ACT) approach; demonstrated induction of anti-oncogenic and anti-PD-L1 miRNAs

A 60-year-old woman with stage IV rectal cancer received adoptive cell therapy with autologous cancer antigen (AC-ACT) causing induction of anti-oncogenic and anti-PD-L1 miRNAs as assessed by miRNA microarray. More than 1 year after AC-ACT, metastases have been arrested, and the patient reports good quality of life.

Derepression of co-silenced tumor suppressor genes by nanoparticle-loaded circular ssDNA reduces tumor malignancy

The co-silencing of multiple tumor suppressor genes can lead to escalated malignancy in cancer cells. Given the limited efficacy of anticancer therapies targeting single tumor suppressor genes, we developed small circular single-stranded DNA (CSSD) that can up-regulate the expression of co-silenced tumor suppressor genes by sequestering microRNAs (miRNAs) that negatively regulate these genes. We found that cancer patients with low tumor expression of the tumor suppressor genes KLF17, CDH1, and LASS2 had shortened survival times. The up-regulation of these genes upon transfection of artificial CSSD-9 inhibited tumor proliferation and metastasis and promoted apoptosis in vitro as well as in ex vivo and patient-derived xenograft models. In addition, CSSD is more stable and effective than current miRNA inhibitors, and transfecting CSSDs via nanoparticles substantially improved delivery efficiency. The use of a single CSSD can promote the inhibition of multiple tumor suppressor genes. This study provides evidence for the possibility of using CSSDs as therapeutic miRNA inhibitors to target the co-silencing of multiple tumor suppressor genes.

Noncoding RNAs Act as Tumor-Derived Molecular Components in Inducing Premetastatic Niche Formation

Cancer metastasis has been demonstrated as it is the culmination of a cascade of priming steps. Increasing evidence has shown that tumor-derived molecular components (TDMCs) are known as extra cellular vesicle and nonvesicle factors and serve as versatile intercellular communication vehicles which can mediate signaling in the tumor microenvironment while creating the premetastatic niche. Noncoding RNAs (ncRNAs) as one of the TDMCs have been proved in participating in the formation of the premetastatic niche. Understanding the premetastatic niche formation mechanisms through TDMCs, especially ncRNAs may open a new avenue for cancer metastasis therapeutic strategies. In this review, recent findings regarding ncRNAs function were summarized, and then the interaction with the premetastatic niche formation was studied, which highlight the potential of using ncRNAs for cancer diagnosis and therapeutic effect.

Inhibition of SIRT1 by microRNA-9, the key point in process of LPS-induced severe inflammation

Severe inflammation may lead to multiple organs dysfunction syndrome, which has a high mortality. MicroRNA is found participated in this process. In this study we developed a lipopolysaccharide-induced inflammation cell model on macrophages and a lipopolysaccharide-induced inflammation mouse model. It was found that during inflammation, microRNA-9 was increased, accompanied with the up-regulation of pro-inflammatory cytokines and anti-inflammatory cytokines. Down-regulation of microRNA-9 inhibited the up-regulation of inflammatory cytokines, promoted the up-regulation of anti-inflammatory cytokines and induced the remission of organ damage, showing a protective effect in inflammation. Bioinformatics analysis combined with luciferase reporter assay showed that SIRT1 was the target gene of microRNA-9. Transfection of microRNA-9 inhibitor could increase the level of SIRT1 and decrease the activation of NF-κB pathway in macrophages. Myeloid specific sirt1 knockout mice were included and we found that lack of SIRT1 in mice macrophages led to aggravated inflammation, cell apoptosis and organ injury, and eliminated the protective property of microRNA-9 inhibitor. In conclusion, we demonstrated that inhibition of microRNA-9 could alleviate inflammation through the up-regulation of SIRT1 and then suppressed the activation of NF-κB pathway. This is a meaningful explore about the specific mechanism of microRNA-9 in inflammation.

Interplay between the androgen receptor signaling axis and microRNAs in prostate cancer

The androgen receptor (AR) is a ligand-activated transcription factor that drives prostate cancer. Since therapies that target the AR are the mainstay treatment for men with metastatic disease, it is essential to understand the molecular mechanisms underlying oncogenic AR signaling in the prostate. miRNAs are small, non-coding regulators of gene expression that play a key role in prostate cancer and are increasingly recognized as targets or modulators of the AR signaling axis. In this review, we examine the regulation of AR signaling by miRNAs and vice versa and discuss how this interplay influences prostate cancer growth, metastasis and resistance to therapy. Finally, we explore the potential clinical applications of miRNAs implicated in the regulation of AR signaling in this prevalent hormone-driven disease.

MicroRNA expression profiling of lung adenocarcinoma in Xuanwei, China: A preliminary study

MicroRNAs (miRNAs) have been proved to be related to the development and progression of lung cancer. However, the expression signatures of miRNAs in lung adenocarcinoma in Xuanwei are not yet clear. The current study aimed to identify the potential miRNA profiles in lung adenocarcinoma in Xuanwei by microarray.The miRNA profiles in 24 lung adenocarcinoma and paired non-tumor tissues in Xuanwei were ascertained by using the Exiqon miRCURY LNA microRNA Array (v.18.0). The results of the microarrays were further verified by quantitative real-time polymerase chain reaction (qRT-PCR) detection. Bioinformatics analysis was used to carry out the functional annotations of differentially expressed miRNAs.One hundred fifty five differentially expressed (≥2-fold change) miRNAs were identified (65 upregulated and 90 downregulated). QRT-PCR was used to validate the top 4 most upregulated and downregulated miRNAs, and the results were generally consisted with microarray. Furthermore, the differentially expressed miRNAs were significantly enriched in numerous common pathways that were bound up with cancer. The pathways included focal adhesion and signaling pathways, such as cyclic guanosine monophosphate -protein kinase G (cGMP-PKG) signaling pathways, mitogen-activated protein kinase (MAPK) signaling pathway, and Hippo signaling pathway, etc.Our study identified the potential miRNA profiles in lung adenocarcinoma in Xuanwei by microarray. These miRNAs might be used as biomarkers for diagnosis and/or prognosis for lung cancer in Xuanwei and therefore warrant further investigation. Further study is needed to reveal the potential role of these miRNAs in the carcinogenesis of XuanWei Lung Cancer (XWLC).

The Functional Role of Prostate Cancer Metastasis-related Micro-RNAs

The mortality of patients with hormone-resistant prostate cancer can be ascribed to a large degree to metastasis to distant organs, predominantly to the bones. In this review, we discuss the contribution of micro-RNAs (miRs) to the metastatic process of prostate cancer. The criteria for selection of miRs for this review were the availability of preclinical in vivo metastasis-related data in conjunction with prognostic clinical data. Depending on their function in the metastatic process, the corresponding miRs are up- or down-regulated in prostate cancer tissues when compared to matching normal tissues. Up-regulated miRs preferentially target suppressors of cytokine signaling or tumor suppressor-related genes and metastasis-inhibitory transcription factors. Down-regulated miRs promote epithelial-mesenchymal transition or mesenchymal-epithelial transition and diverse pro-metastatic signaling pathways. Some of the discussed miRs exert their function by simultaneously targeting epigenetic pathways as well as cell-cycle-related, anti-apoptotic and signaling-promoting targets. Finally, we discuss potential therapeutic options for the treatment of prostate cancer-related metastases by substitution or inhibition of miRs.

Inhibition of miR-9-5p suppresses prostate cancer progress by targeting StarD13

Background

This study aims to investigate the effects of inhibiting microRNA-9-5p (miR-9-5p) on the expression of StAR-related lipid transfer domain containing 13 (StarD13) and the progress of prostate cancer.

Methods

The mRNA expression levels of miR-9-5p and StarD13 were determined in several prostate cancer cell lines. We chose DU145 and PC-3 cells for further research. The CCK8 assay was used to measure the cell viability. The cell invasion and wound-healing assays were respectively applied to evaluate invasion and migration. The expression of E-cadherin (E-cad), N-cadherin (N-cad) and vimentin were measured via western blot. DU145 and PC-3 cells overexpressing StarD13 were generated to investigate the variation in proliferation, invasion and migration. A luciferase reporter assay was used to identify the target of miR-9-5p.

Results

Our results show that miR-9-5p was highly expressed and StarD13 was suppressed in prostate cancer cells. MiR-9-5p inhibition repressed the cells’ viability, invasion and migration. It also increased the expression of E-cad and decreased that of N-cad and vimentin. StarD13 overexpression gave the same results as silencing of miR-9-5p: suppression of cell proliferation, invasion and migration. The bioinformatics analysis predicted StarD13 as a target gene of miR-9-5p. Quantitative RT-PCR, western blot analysis and the dual-luciferase reporter assay were employed to confirm the prediction.

Conclusion

Our results show that miR-9-5p plays a powerful role in the growth, invasion, migration and epithelial–mesenchymal transition (EMT) of prostate cancer cells by regulating StarD13. A therapeutic agent inhibiting miR-9-5p could act as a tumor suppressor for prostate cancer.

MiR-9 promotes tumorigenesis and angiogenesis and is activated by MYC and OCT4 in human glioma

BACKGROUND

Glioma, characterized by its undesirable prognosis and poor survival rate, is a serious threat to human health and lives. MicroRNA-9 (miR-9) is implicated in the regulation of multiple tumors, while the mechanisms underlying its aberrant expression and functional alterations in human glioma are still controversial.

METHODS

Expressions of miR-9 were measured in GEO database, patient specimens and glioma cell lines. Gain- and loss-of-function assays were applied to identify the effects of miR-9 on glioma cells and HUVECs in vitro and in vivo. Potential targets of miR-9 were predicted by bioinformatics and further verified via in vitro experiments. Transcriptional regulation of miR-9 by MYC and OCT4 was determined in glioma cells.

RESULTS

MiR-9 was frequently up-regulated in glioma specimens and cells, and could significantly enhance proliferation, migration and invasion of glioma cells. In addition, miR-9 could be secreted from glioma cells via exosomes and was then absorbed by vascular endothelial cells, leading to an increase in angiogenesis. COL18A1, THBS2, PTCH1 and PHD3 were verified as the direct targets of miR-9, which could elucidate the miR-9-induced malignant phenotypes in glioma cells. MYC and OCT4 were able to bind to the promoter region of miR-9 to trigger its transcription.

CONCLUSIONS

Our results highlight that miR-9 is pivotal for glioma pathogenesis and can be treated as a potential therapeutic target for glioma.

MicroRNAs in prostate cancer: From function to biomarker discovery

MicroRNAs (miRNAs) are a small functional non-coding RNAs that post-transcriptionally regulate gene expression through mRNA degradation or translational repression. miRNAs are key regulatory components of various cellular networks. Current evidence support that multiple mammalian genome-encoded miRNAs impact the cellular biology, including proliferation, apoptosis, differentiation, and tumorigenesis, by targeting specific subsets of mRNAs. This minireview is focused on the current themes underlying the interactions between miRNAs and their mRNA targets and pathways in prostate tumorigenesis and progression, and their potential clinical utility as biomarkers for prostate cancer. Impact statement The primary goal of this article was to review recent literature on miRNA biogenesis and further elaborate on the identity of newly discovered miRNAs and their potential functional significance in the complex biological network associated with prostate tumorigenesis and disease progression and as biomarkers for prostate cancer.

miR-9 knockdown inhibits hypoxia-induced cardiomyocyte apoptosis by targeting Yap1

AIMS

Aberrantly expressed miRNAs are demonstrated to be involved in the development of congenital heart disease (CHD). miR-9 was proposed to be upregulated in cardiac tissues from CHD cases. However, the role of miR-9 in hypoxia-induced cardiomyocytes and the potential mechanism are far from being addressed.

MAIN METHODS

qRT-PCR and western blot analysis were performed to detect miR-9 and Yes-associated protein 1 (Yap1) expressions in hypoxic H9c2 cells. CCK-8, flow cytometry analysis, caspase-3/7 activity assay were applied to evaluate cell proliferation, apoptosis, and caspase-3/7 activity, respectively. The interaction between miR-9 and Yap1 was explored by luciferase reporter assay, qRT-PCR and western blot.

KEY FINDINGS

miR-9 was upregulated and Yap1 was downregulated in H9c2 cells in response to hypoxia in a time-dependent manner. Knockdown of miR-9 promoted cell proliferation, and inhibited apoptosis and caspase-3/7 activity in hypoxic H9c2 cells, while miR-9 overexpression exerted the opposite effects on hypoxic H9c2 cells. In addition, Yap1 was a direct target of miR-9 in H9c2 cells. Yap1 knockdown suppressed cell proliferation and promoted apoptosis in hypoxia-exposed H9c2 cells. Yap1 knockdown attenuated the effect of anti-miR-9 on cell proliferation and apoptosis in hypoxia-exposed H9c2 cells.

SIGNIFICANCE

miR-9 knockdown inhibited hypoxia-induced cardiomyocyte apoptosis by targeting Yap1. Our study provided a novel insight into the mechanism of the adaptation of cardiomyocytes to chronic hypoxia.

HOXA9 methylation and blood vessel invasion in FFPE tissues for prognostic stratification of stage I lung adenocarcinoma patients

OBJECTIVES

Surgery with curative intent is the standard treatment for stage I lung adenocarcinoma. However, disease recurrence occurs in a third of patients. Prognostic biomarkers are needed to improve postoperative management. Here, we evaluate the utility of Homeobox A9 (HOXA9) promoter methylation, alone or in combination with Blood Vessel Invasion (BVI) assessment, for prognostic stratification of stage I lung adenocarcinoma patients.

MATERIALS AND METHODS

We developed a Droplet Digital PCR (ddPCR) assay to measure HOXA9 promoter methylation in formalin-fixed paraffin-embedded (FFPE) biospecimens generated during routine pathology. The prognostic value of HOXA9 promoter methylation and BVI, alone and in combination, was evaluated by Kaplan-Meier survival and Cox regression analyses in a cohort of 177 stage I lung adenocarcinoma patients from the NCI-MD study.

RESULTS

The ddPCR assay showed linearity, sensitivity and specificity for measuring HOXA9 promoter methylation down to 0.1% methylated DNA input. The HOXA9 promoter was methylated de novo in FFPE tumors (P < 0.0001). High methylation was independently associated with worse cancer-specific survival (Hazard Ratio [HR], 3.37; P = 0.0002) and identified high-risk stage IA and IB patients. Addition of this molecular marker improved a risk model comprised of clinical and pathologic parameters (age, gender, race, stage, and smoking history; nested likelihood ratio test; P = 0.0004) and increased the C-index from 0.60 (95% CI 0.51-0.69) to 0.68 (0.60-0.76). High methylation tumors displayed high frequency of TP53 mutations and other molecular characteristics associated with aggressiveness. BVI was independently associated with poor outcome (HR, 2.62; P = 0.054). A score that combined BVI with HOXA9 promoter methylation further stratified high-risk patients (trend P = 0.0001 comparing 0, 1 or 2 positive markers).

CONCLUSIONS

ddPCR can be used to quantify HOXA9 promoter methylation in FFPE samples. Alone or combined with BVI in a prognostic classifier, HOXA9 promoter methylation could potentially inform the clinical management of patients with early-stage lung adenocarcinoma.

Lamins in Lung Cancer: Biomarkers and Key Factors for Disease Progression through miR-9 Regulation?

Lung cancer represents the primary cause of cancer death in the world. Malignant cells identification and characterization are crucial for the diagnosis and management of patients with primary or metastatic cancers. In this context, the identification of new biomarkers is essential to improve the differential diagnosis between cancer subtypes, to select the most appropriate therapy, and to establish prognostic correlations. Nuclear abnormalities are hallmarks of carcinoma cells and are used as cytological diagnostic criteria of malignancy. Lamins (divided into A- and B-types) are localized in the nuclear matrix comprising nuclear lamina, where they act as scaffolding protein, involved in many nuclear functions, with regulatory effects on the cell cycle and differentiation, senescence and apoptosis. Previous studies have suggested that lamins are involved in tumor development and progression with opposite results concerning their prognostic role. This review provides an overview of lamins expression in lung cancer and the relevance of these findings for disease diagnosis and prognosis. Furthermore, we discuss the link between A-type lamins expression in lung carcinoma cells and nuclear deformability, epithelial to mesenchymal transition, and metastatic potential, and which mechanisms could regulate A-type lamins expression in lung cancer, such as the microRNA miR-9.

Sex-specific microRNA expression networks in an acute mouse model of ozone-induced lung inflammation

BACKGROUND

Sex differences in the incidence and prognosis of respiratory diseases have been reported. Studies have shown that women are at increased risk of adverse health outcomes from air pollution than men, but sex-specific immune gene expression patterns and regulatory networks have not been well studied in the lung. MicroRNAs (miRNAs) are environmentally sensitive posttranscriptional regulators of gene expression that may mediate the damaging effects of inhaled pollutants in the lung, by altering the expression of innate immunity molecules.

METHODS

Male and female mice of the C57BL/6 background were exposed to 2 ppm of ozone or filtered air (control) for 3 h. Female mice were also exposed at different stages of the estrous cycle. Following exposure, lungs were harvested and total RNA was extracted. We used PCR arrays to study sex differences in the expression of 84 miRNAs predicted to target inflammatory and immune genes.

RESULTS

We identified differentially expressed miRNA signatures in the lungs of male vs. female exposed to ozone. In silico pathway analyses identified sex-specific biological networks affected by exposure to ozone that ranged from direct predicted gene targeting to complex interactions with multiple intermediates. We also identified differences in miRNA expression and predicted regulatory networks in females exposed to ozone at different estrous cycle stages.

CONCLUSION

Our results indicate that both sex and hormonal status can influence lung miRNA expression in response to ozone exposure, indicating that sex-specific miRNA regulation of inflammatory gene expression could mediate differential pollution-induced health outcomes in men and women.

Sulforaphane epigenetically demethylates the CpG sites of the miR-9-3 promoter and reactivates miR-9-3 expression in human lung cancer A549 cells

Increasing evidence suggests that epigenetic aberrations contribute to the development and progression of cancers such as lung cancer. The promoter region of miR-9-3 was recently found to be hypermethylated in lung cancer, resulting in down-regulation of miR-9-3 and poor patient prognosis. Sulforaphane (SFN), a natural compound that is obtained from cruciferous vegetables, has potent anticancer activities. In this study, we aimed to investigate the effect of SFN on restoring the miR-9-3 level in lung cancer A549 cells through epigenetic regulation. DNA methylation of the miR-9-3 promoter was examined using bisulfite genomic sequencing and methylated DNA immunoprecipitation analysis. The expression levels of miR-9-3 and several epigenetic modifying enzymes were measured using quantitative real-time polymerase chain reaction and Western blotting, respectively. The transcriptional activity of the miR-9-3 promoter was evaluated by patch methylation, and histone modifications were analyzed using chromatin immunoprecipitation (ChIP) assays. We found that CpG methylation was reduced in the miR-9-3 promoter and that miR-9-3 expression was increased after 5 days of treatment with SFN. In vitro methylation analysis showed that the methylated recombinant construct exhibited lower luciferase reporter activity than the unmethylated counterpart. ChIP assays revealed that SFN treatment increased H3K4me1 enrichment at the miR-9-3 promoter. Furthermore, SFN treatment attenuated enzymatic DNMT activity and DNMT3a, HDAC1, HDAC3, HDAC6 and CDH1 protein expression. Taken together, these findings indicate that SFN may exert its chemopreventive effects partly through epigenetic demethylation and restoration of miR-9-3.

MicroRNA‑320 targets mitogen‑activated protein kinase 1 to inhibit cell proliferation and invasion in epithelial ovarian cancer

Ovarian cancer is the second most frequently occurring cancer and the most fatal gynecological malignancy of all gynecological cancers worldwide. MicroRNAs (miR) have been reported to be downregulated or upregulated in a variety of human malignancies, and involved in the formation and progression of the majority of human cancers, including epithelial ovarian cancer (EOC). miR‑320 has been identified as a tumor suppressor in multiple human cancers. However, the expression levels, biological role and underlying mechanisms of miR‑320 in EOC remain to be elucidated. In the present study, reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was performed to detect miR‑320 expression in EOC tissues and cell lines. Following transfection with miR‑320 mimics, Cell Counting Kit 8 and cell invasion assays were utilized to investigate the effects of miR‑320 on EOC cell proliferation and invasion. Bioinformatic analysis, luciferase reporter assay, RT‑qPCR and western blotting were used to explore the underlying mechanism of how miR‑320 affects cell proliferation and invasion in EOC. Mitogen‑activated protein kinase (MAPK) 1 expression and its association with the miR‑320 expression level was examined in EOC tissues. The role of MAPK1 in EOC cells was additionally evaluated by using a loss‑of‑function assay. The results demonstrated that miR‑320 was markedly downregulated in EOC tissues and cell lines. A decreased miR‑320 expression was significantly correlated with the Federation of Gynecology and Obstetrics stage and lymph node metastasis of EOC patients. Additionally, reintroduction of miR‑320 expression suppressed cell proliferation and invasion in EOC. Furthermore, it was verified that MAPK1 is a direct target gene of miR‑320 in EOC. MAPK1 expression was markedly upregulated in EOC tissues and inversely correlated with miR‑320 expression. Furthermore, silencing of MAPK1 by RNA interference inhibited cell proliferation and invasion of EOC cells. Overall, the present study demonstrated that miR‑320 may act as a useful diagnostic and therapeutic target in the treatment of EOC.

LINC00461, a long non-coding RNA, is important for the proliferation and migration of glioma cells

An increasing number of reports have revealed that long non-coding RNAs are important players in tumorigenesis. Here we showed that long non-coding RNA LINC00461 is highly expressed in glioma tissues compared to non-neoplastic brain tissues. The knockdown of LINC00461 suppressed cyclinD1/A/E expression which led to G0/G1 cell cycle arrest and inhibited cell proliferation in glioma cells. LINC00461 suppression also inhibited glioma cell migration and invasion. The function of LINC00461 in glioma cells is partially mediated by MAPK/ERK and PI3K/AKT signaling pathways as down-regulation of LINC00461 expression suppressed ERK1/2 and AKT activities. Moreover, LINC00461 knockdown decreased expression levels of microRNA miR-9 and flanking genes MEF2C and TMEM161B. Taken together, our results demonstrate that LINC00461 is important for glioma progression affecting cell proliferation, migration and invasion via MAPK/ERK, PI3K/AKT, and possibly other signaling pathways.

MiR-9 is involved in TGF-β1-induced lung cancer cell invasion and adhesion by targeting SOX7

MicroRNA (miR)‐9 plays different roles in different cancer types. Here, we investigated the role of miR‐9 in non‐small‐cell lung cancer (NSCLC) cell invasion and adhesion in vitro and explored whether miR‐9 was involved in transforming growth factor‐beta 1 (TGF‐β1)‐induced NSCLC cell invasion and adhesion by targeting SOX7. The expression of miR‐9 and SOX7 in human NSCLC tissues and cell lines was examined by reverse transcription‐quantitative polymerase chain reaction. Gain‐of‐function and loss‐of‐function experiments were performed on A549 and HCC827 cells to investigate the effect of miR‐9 and SOX7 on NSCLC cell invasion and adhesion in the presence or absence of TGF‐β1. Transwell–Matrigel assay and cell adhesion assay were used to examine cell invasion and adhesion abilities. Luciferase reporter assay was performed to determine whether SOX7 was a direct target of miR‐9. We found miR‐9 was up‐regulated and SOX7 was down‐regulated in human NSCLC tissues and cell lines. Moreover, SOX7 expression was negatively correlated with miR‐9 expression. miR‐9 knockdown or SOX7 overexpression could suppress TGF‐β1‐induced NSCLC cell invasion and adhesion. miR‐9 directly targets the 3′ untranslated region of SOX7, and SOX7 protein expression was down‐regulated by miR‐9. TGF‐β1 induced miR‐9 expression in NSCLC cells. miR‐9 up‐regulation led to enhanced NSCLC cell invasion and adhesion; however, these effects could be attenuated by SOX7 overexpression. We concluded that miR‐9 expression was negatively correlated with SOX7 expression in human NSCLC. miR‐9 was up‐regulated by TGF‐β1 and contributed to TGF‐β1‐induced NSCLC cell invasion and adhesion by directly targeting SOX7.

Mutual regulation of microRNAs and DNA methylation in human cancers

microRNAs (miRNAs) and DNA methylation are the 2 epigenetic modifications that have emerged in recent years as the most critical players in the regulation of gene expression. Compelling evidence has indicated the roles of miRNAs and DNA methylation in modulating cellular transformation and tumorigenesis. miRNAs act as negative regulators of gene expression and are involved in the regulation of both physiologic conditions and during diseases, such as cancer, inflammatory diseases, and psychiatric disorders, among others. Meanwhile, aberrant DNA methylation manifests in both global genome changes and in localized gene promoter changes, which influences the transcription of cancer genes. In this review, we described the mutual regulation of miRNAs and DNA methylation in human cancers. miRNAs regulate DNA methylation by targeting DNA methyltransferases or methylation-related proteins. On the other hand, both hyper- and hypo-methylation of miRNAs occur frequently in human cancers and represent a new level of complexity in gene regulation. Therefore, understanding the mechanisms underlying the mutual regulation of miRNAs and DNA methylation may provide helpful insights in the development of efficient therapeutic approaches.

Oxidative stress in prostate hyperplasia and carcinogenesis

Prostatic hyperplasia (PH) is a common urologic disease that affects mostly elderly men. PH can be classified as benign prostatic hyperplasia (BPH), or prostate cancer (PCa) based on its severity. Oxidative stress (OS) is known to influence the activities of inflammatory mediators and other cellular processes involved in the initiation, promotion and progression of human neoplasms including prostate cancer. Scientific evidence also suggests that micronutrient supplementation may restore the antioxidant status and hence improve the clinical outcomes for patients with BPH and PCa. This review highlights the recent studies on prostate hyperplasia and carcinogenesis, and examines the role of OS on the molecular pathology of prostate cancer progression and treatment.