MicroRNA-490 regulates lung cancer metastasis by targeting poly r(C)-binding protein 1

Small RNA sequencing identified miR-3180 as a potential prognostic biomarker for Chinese hepatocellular carcinoma patients

MicroRNAs (miRNAs) and their target genes are aberrantly expressed in many cancers and are linked to carcinogenesis and metastasis, especially among hepatocellular carcinoma (HCC) patients. This study sought to identify new biomarkers related to HCC prognosis using small RNA sequencing from the tumor and matched normal adjacent tissue of 32 patients with HCC. Eight miRNAs were downregulated and 61 were upregulated more than twofold. Of these, five miRNAs, hsa-miR-3180, hsa-miR-5589-5p, hsa-miR-490-5p, hsa-miR-137, and hsa-miR-378i, were significantly associated with 5-year overall survival (OS) rates. Differential upregulation of hsa-miR-3180 and downregulation of hsa-miR-378i in tumor samples supported the finding that low and high concentrations of hsa-miR-3180 (p = 0.029) and hsa-miR-378i (p = 0.047), respectively, were associated with higher 5-year OS. Cox regression analyses indicated that hsa-miR-3180 (HR = 0.08; p = 0.013) and hsa-miR-378i (HR = 18.34; p = 0.045) were independent prognostic factors of poor survival. However, high hsa-miR-3180 expression obtained larger AUCs for OS and progression-free survival (PFS) and had better nomogram prediction than hsa-miR-378i. These findings indicate that hsa-miR-3180 may be associated with HCC progression and could serve as a potential biomarker for this disease.

Long non-coding RNAs: an overview on miRNA sponging and its co-regulation in lung cancer

Lung cancer is the most devastating cause of death among all cancers worldwide, and non-small cell lung cancer (NSCLC) accounts for 80% of all the lung cancer cases. Beyond common genetic research and epigenomic studies, the extraordinary investigations of non-coding RNAs have provided insights into the molecular basis of cancer. Existing evidence from various cancer models highlights that the regulation of non-coding RNAs is crucial and that their deregulation may be a common reason for the development and progression of cancer, and competition of cancer therapeutics. Non-coding RNAs, such as long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), are increasingly recognized as potential cancer biomarkers for early detection and application of therapeutic strategies. The miRNAs have gained importance as master regulators of target mRNAs by negatively regulating their expression. The lncRNAs function as both tumor suppressors and oncogenes, and also compete with miRNAs that influence the translational inhibition processes. This review addresses the role of lncRNAs in lung cancer development, highlights their mechanisms of action, and provides an overview of the impact of lncRNAs on lung cancer survival and progression via miRNA sponging. The improved understanding of lung cancer mechanisms has opened opportunities to analyze molecular markers and their potential therapeutics.

Screening key prognostic factors and constructing survival prognostic risk prediction model based on ceRNA network in early lung adenocarcinoma

Background

We aim to discover some prognostic factors, provide a basis for discovering molecular markers, and provide a basis for molecular features of early lung adenocarcinoma (LUAD) to predict patient prognosis.

Methods

Sequence data of LUAD were downloaded from The Cancer Genome Atlas (TCGA) database to screen out differentially expressed lncRNAs, miRNAs, and mRNAs (DERs). DERs were identified using R software’s limma package. The competitive endogenous RNA (ceRNA) network was constructed based on these RNAs. Univariate and multivariate Cox regression analysis on the RNAs in the ceRNA screened out independent prognostic-related RNAs to construct a prognostic risk score (PS) model. Combined with clinical data, we can calculate the survival rate of patients with early LUAD.

Results

There were 2,701 differentially expressed mRNAs (DEmRNAs), 47 differentially expressed lncRNAs (DElncRNAs), and 161 differentially expressed miRNAs (DEmiRNAs) identified in early LUAD. Based on these RNAs, 32 lncRNAs, 87 miRNAs, and 174 mRNAs participated in the ceRNA network. Twelve independently prognostic-related RNAs form an optimized combination. We developed a PS model based on these RNAs. Age, tumor recurrence and PS model status were independent survival prognostic clinical factors. Nomogram was established to predict the 3-year and 5-year survival rates.

Conclusions

We successfully constructed a ceRNA regulatory network based on the DERs in early LUAD. It can help us clarify the molecular mechanism of early LUAD. Simultaneously, the prognostic-related RNAs in early LUAD were also screened out. This network could provide new bases for diagnoses and prognoses of patients with LUAD.

MicroRNAs in Cancer: From Gene Expression Regulation to the Metastatic Niche Reprogramming

By 2003, the Human Genome project had been completed; however, it turned out that 97% of genome sequences did not encode proteins. The explanation came later when it was found the untranslated DNA contain sequences for short microRNAs (miRNAs) and long noncoding RNAs that did not produce any mRNAs or tRNAs, but instead were involved in the regulation of gene expression. Initially identified in the cytoplasm, miRNAs have been found in all cell compartments, where their functions are not limited to the degradation of target mRNAs. miRNAs that are secreted into the extracellular space as components of exosomes or as complexes with proteins, participate in morphogenesis, regeneration, oncogenesis, metastasis, and chemoresistance of tumor cells. miRNAs play a dual role in oncogenesis: on one hand, they act as oncogene suppressors; on the other hand, they function as oncogenes themselves and inactivate oncosuppressors, stimulate tumor neoangiogenesis, and mediate immunosuppressive processes in the tumors, The review presents current concepts of the miRNA biogenesis and their functions in the cytoplasm and nucleus with special focus on the noncanonical mechanisms of gene regulation by miRNAs and involvement of miRNAs in oncogenesis, as well as the authors' opinion on the role of miRNAs in metastasis and formation of the premetastatic niche.

MicroRNA-490-3p and -490-5p in carcinogenesis: Separate or the same goal?

MicroRNA (miR)-490-3p and miR-490-5p, located on chromosome 7q33, are two independent mature products of miR-490 exerting distinct effects on tumor progression. miR-490-3p and miR-490-5p possess antitumor properties. miR-490-3p dysfunction has been associated with malignancies including colorectal cancer, while the abnormal function of miR-490-5p has been more considerably associated with bladder cancer (for example). At present, there are 30 and 11 target genes of miR-490-3p and miR-490-5p, respectively, that have been experimentally verified, of which the cyclin D1 (CCND1) gene is a common target. Through these target genes, miR-490-3p and miR-490-5p are involved in 7 and 3 signaling pathways, respectively, of which only 2 are shared regulatory signaling pathways. The present review introduces two competing endogenous RNA (ceRNA) regulatory networks centered on miR-490-3p and miR-490-5p. These networks may be important promoters of tumor cell proliferation, invasiveness, metastatic potential and apoptosis. Unlike miR-490-5p, miR-490-3p plays a unique role in promoting cancer. However, both are promising molecular markers for early cancer diagnosis and prognosis. In addition, miR-490-3p was also found to be associated with the chemical resistance of cisplatin and paclitaxel. The present review focuses on the abnormal expression of miR-490-3p and miR-490-5p in different tumor types, and their complex ceRNA regulatory networks. The clinical value of miR-490-3p and miR-490-5p in cancer diagnosis, prognosis and treatment is also clarified, and an explanation for the opposing effects of miR-490-3p in tumor research is provided.

Expression and regulatory roles of lncRNAs in G-CIMP-low vs G-CIMP-high Glioma: an in-silico analysis

BACKGROUND

Clinically relevant glioma subtypes, such as the glioma-CpG island methylator phenotype (G-CIMP), have been defined by epigenetics. In this study, the role of long non-coding RNAs in association with the poor-prognosis G-CMIP-low phenotype and the good-prognosis G-CMIP-high phenotype was investigated. Functional associations of lncRNAs with mRNAs and miRNAs were examined to hypothesize influencing factors of the aggressive phenotype.

METHODS

RNA-seq data on 250 samples from TCGA's Pan-Glioma study, quantified for lncRNA and mRNAs (GENCODE v28), were analyzed for differential expression between G-CIMP-low and G-CIMP-high phenotypes. Functional interpretation of the differential lncRNAs was performed by Ingenuity Pathway Analysis. Spearman rank order correlation estimates between lncRNA, miRNA, and mRNA nominated differential lncRNA with a likely miRNA sponge function.

RESULTS

We identified 4371 differentially expressed features (mRNA = 3705; lncRNA = 666; FDR ≤ 5%). From these, the protein-coding gene TP53 was identified as an upstream regulator of differential lncRNAs PANDAR and PVT1 (p = 0.0237) and enrichment was detected in the "development of carcinoma" (p = 0.0176). Two lncRNAs (HCG11, PART1) were positively correlated with 342 mRNAs, and their correlation estimates diminish after adjusting for either of the target miRNAs: hsa-miR-490-3p, hsa-miR-129-5p. This suggests a likely sponge function for HCG11 and PART1.

CONCLUSIONS

These findings identify differential lncRNAs with oncogenic features that are associated with G-CIMP phenotypes. Further investigation with controlled experiments is needed to confirm the molecular relationships.

miR-490: A potential biomarker and therapeutic target in cancer and other diseases

MicroRNAs (miRNAs) are small non-coding RNAs that function as posttranscriptional gene regulators. Among a pool of >2600 known human mature miRNAs, only a small subset have been functionally interrogated and a further smaller pool shown to be associated with the pathogenesis of a variety of diseases suggesting their critical role in maintaining homeostasis. Here, we draw your attention to one such miRNA, miR-490, that has been reported to be deregulated in a myriad of diseases (23 diseases) ranging from cardiomyopathy, depression, and developmental disorders to many cancer types (28 cancer types), such as hepatocellular carcinoma, gastric cancer, cancers of the reproductive and central nervous system among others. The prognostic and diagnostic potential of miR-490 has been reported in many diseases including cancer underlining its clinical relevance. We also collate a complex plethora of epigenetic (histone and DNA methylation), transcriptional (TF), and posttranscriptional (lncRNA and circRNA) mechanisms that have been shown to tightly regulate miR-490 levels. The targets of miR-490 involve a range of cancer-related genes involved in the regulation of various cancer hallmarks like cell proliferation, migration, and invasion, apoptotic cell death, angiogenesis, and so forth. Overall, our in-depth review highlights for the first time the emerging role of miR-490 in disease pathology, diagnosis, and prognosis that assigns a unique therapeutic potential to miR-490 in the era of precision medicine.

Multilevel regulation and molecular mechanism of poly (rC)-binding protein 1 in cancer

Poly (rC)-binding protein 1 (PCBP1), an RNA- or DNA-binding protein with a relative molecular weight of 38 kDa, which is characterized by downregulation in many cancer types. Numerous cases have indicated that PCBP1 could be considered as a tumor suppressor to inhibit tumorigenesis, development, and metastasis. In the current review, we described the multilevel regulatory roles of PCBP1, including gene transcription, alternative splicing, and translation of many cancer-related genes. Additionally, we also provided a brief overview about the inhibitory effect of PCBP1 on most common tumors. More importantly, we summarized the current research status about PCBP1 in hypoxic microenvironment, autophagy, apoptosis, and chemotherapy of cancer cells, aiming to clarify the molecular mechanisms of PCBP1 in cancer. Taken together, in-depth study of PCBP1 in cancer may provide new ideas for cancer therapy.

The HMGB1-2 Ovarian Cancer Interactome. The Role of HMGB Proteins and Their Interacting Partners MIEN1 and NOP53 in Ovary Cancer and Drug-Response

High mobility group box B (HMGB) proteins are overexpressed in different types of cancers such as epithelial ovarian cancers (EOC). We have determined the first interactome of HMGB1 and HMGB2 in epithelial ovarian cancer (the EOC-HMGB interactome). Libraries from the SKOV-3 cell line and a primary transitional cell carcinoma (TCC) ovarian tumor were tested by the Yeast Two Hybrid (Y2H) approach. The interactome reveals proteins that are related to cancer hallmarks and their expression is altered in EOC. Moreover, some of these proteins have been associated to survival and prognosis of patients. The interaction of MIEN1 and NOP53 with HMGB2 has been validated by co-immunoprecipitation in SKOV-3 and PEO1 cell lines. SKOV-3 cells were treated with different anti-tumoral drugs to evaluate changes in HMGB1, HMGB2, MIEN1 and NOP53 gene expression. Results show that combined treatment of paclitaxel and carboplatin induces a stronger down-regulation of these genes in comparison to individual treatments. Individual treatment with paclitaxel or olaparib up-regulates NOP53, which is expressed at lower levels in EOC than in non-cancerous cells. On the other hand, bevacizumab diminishes the expression of HMGB2 and NOP53. This study also shows that silencing of these genes affects cell-viability after drug exposure. HMGB1 silencing causes loss of response to paclitaxel, whereas silencing of HMGB2 slightly increases sensitivity to olaparib. Silencing of either HMGB1 or HMGB2 increases sensitivity to carboplatin. Lastly, a moderate loss of response to bevacizumab is observed when NOP53 is silenced.

LncRNA SNHG16 Promotes Proliferation, Migration, and Invasion of Glioma Cells Through Regulating the miR-490/PCBP2 Axis

Background: Glioma is the most common tumor of the central nervous system, which has a high mortality and recurrence rate. Increasing evidence shows that long noncoding RNAs (lncRNA) are closely related to the occurrence of cancer. However, the mechanism of lncRNA small nucleolar RNA host gene 16 (SNHG16) in glioma remains to be studied. Materials and Methods: The expression levels of SNHG16, microRNA-490 (miR-490), and poly(C)-binding proteins 2 (PCBP2) in tissues and cells were determined by quantitative real-time polymerase chain reaction. 3-(4, 5-dimethyl-2 thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) and transwell assays were used to evaluate the proliferation, migration, and invasion abilities of glioma cells. Moreover, Western blot analysis was performed to assess the levels of PCBP2 and proliferation-related and metastasis-related proteins. Dual-luciferase reporter assay was used to verify the interaction among SNHG16, miR-490, and PCBP2. Results: SNHG16 was highly expressed in glioma tissues and cells, and silenced-SNHG16 suppressed the proliferation, migration, and invasion of glioma cells. Besides, SNHG16 could interact with miR-490. The aberrant expression of SNHG16 restored the inhibitory effect of miR-490 overexpression on the proliferation, migration, and invasion of glioma cells. Moreover, PCBP2 was a target of miR-490. MiR-490 inhibitor recovered the suppression effect of PCBP2 knockdown on glioma progression, and PCBP2 overexpression also could reverse the inhibition effect of miR-490 mimic on glioma progression. In addition, SNHG16 promoted the expression of PCBP2, while miR-490 inhibited its expression. Conclusions: The authors' data revealed that SNHG16 might function as an oncogene in glioma through regulating the miR-490/PCBP2 axis, and the elucidating of the mechanism of SNHG16 provided a potential therapeutic target for glioma.

Comprehensive Analysis of Competing Endogenous RNA (ceRNA) Network Based on RNAs Differentially Expressed in Lung Adenocarcinoma Using The Cancer Genome Atlas (TCGA) Database

Background

The aim of this study was to explore a comprehensive analysis of the competing endogenous (ceRNA) network of lung adenocarcinoma and predict its regulatory mechanism and prognosis correlation based on The Cancer Genome Atlas (TCGA) database.

Material/Methods

The genes expression data from 535 lung adenocarcinoma cases and 59 normal tissue cases were acquired and downloaded from TCGA database, and differentially expressed messenger RNA (mRNA), long noncoding RNA (lncRNA) and microRNA (miRNA) were selected primarily by “edgeR” package in R software, which further constructs lncRNA-miRNA-mRNA ceRNA network. We then proceed to carry out Gene Ontology enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and Kaplan-Meier survival analysis of the mRNAs involved in the ceRNA network.

Results

There are 3 mRNAs (ANLN, IGFBP1, and TFAP2A) in differentially expressed genes, 4 lncRNAs (AC015923.1, FGF12-AS2, LINC00211, and MED4-AS1), and 2 miRNAs (miR-31 and miR-490) associated with the prognostic of lung adenocarcinoma. Besides, LINC00461 and has-mir-139 as key nodes were found in the ceRNA network. Significantly, miR-31 shows the greatest prognostic value related to the adverse effect of the prognostic of lung adenocarcinoma (P<0.001).

Conclusions

By analyzing the expression data of lung adenocarcinoma in TCGA database, we found that 3 mRNAs, 4 lncRNAs, and 2 miRNAs were screened as potential prognostic factors for lung adenocarcinoma. In addition, LINC00461 and has-mir-139 are 2 important regulatory network nodes in lung adenocarcinoma ceRNA.

Evaluation of Exosomal miRNA in Blood as a Potential Diagnostic Biomarker for Human Non-Small Cell Lung Cancer

Background

Tumor-derived exosomes have been used as diagnostic biomarkers to discriminate between tumor patients and healthy people. This study explored the roles of exosomal miRNAs in lung adenocarcinoma metastasis by microarray and developed a novel method for diagnosis of lung adenocarcinoma.

Material/Methods

Four lung adenocarcinoma patients’ peripheral blood, including 2 metastasis and 2 N-metastasis, were used for exosomes miRNA microarray analysis. Exosomes were extracted by ultracentrifugation and identified by transmission electron microscopy. All the raw data were normalized by R software with limma packet. qRT-PCR was used to validate the microarray results. A549 cells were used to identify the functions of miR-4448. Western blot, qRT-PCR, RNAi, CCK8, and transwell invasion assay were used to verify the metastasis and proliferation abilities.

Results

miR-4436a and miR-4687-5p were upregulated between the metastasis and N-metastasis group, while miR-22-3p, miR-3666, miR-4448, miR-4449, miR-6751-5p and miR-92a-3p were downregulated. miR-4448 was also downregulated between the metastasis and control group, whereas there was no significant difference between the N-metastasis group and control group. qRT-PCR confirmed the downregulation of miR-4448 in exosomes from lung adenocarcinoma patients compared with N-metastasis patients and healthy people. CCK8 and transwell invasion assay showed that A549 cells transfected with miR-4448 inhibitor had higher proliferation and metastasis ability. qRT-PCR and Western blot confirmed the high expression of MMP2 and MMP9 in A549 cells transfected with miR-4448 inhibitor.

Conclusions

miR-4448 can inhibit A549 cell proliferation and metastasis. miR-4448 in exosomes has the potential to serve as a diagnostic marker of patients with adenocarcinoma metastasis.

Non-coding RNA profile in lung cancer

Lung cancer is the most frequently diagnosed malignancy and the leading source of cancer-associated mortality. This kind of cancer has heterogeneous nature and is divided into two broad classes of small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). In addition to aberrant expression of several signaling pathways and oncogenes, lung cancer is associated with dysregulation of expression of non-coding RNAs including both long non-coding RNAs (lncRNAs) and miRNAs. These aberrantly expressed transcripts are putative therapeutic targets and diagnostic/ prognostic markers. Integrative assessment of expression of lncRNAs, miRNAs and mRNAs has led to construction of competing endogenous RNA networks in which several lncRNAs act as molecular sponges to inhibit regulatory function of miRNAs on mRNAs. Notably, some of these networks seem to have subtype-specific functions in lung cancer. In this review, we summarize recent findings about the importance of these networks in the pathogenesis of lung cancer and provide a list of onco-miRNAs, tumor suppressor miRNAs, oncogenic lncRNAs and tumor suppressor lncRNAs based on their roles in the carcinogenic process in lung cancer.

Identification of Three Differentially Expressed miRNAs as Potential Biomarkers for Lung Adenocarcinoma Prognosis

OBJECTIVE

The aim of this study areto screen MicroRNAs (miRNAs) related to the prognosis of lung adenocarcinoma (LUAD) and to explore the possible molecular mechanisms.

METHODS

The data for a total of 535 patients with LUAD data were downloaded from The Cancer Genome Atlas (TCGA) database. The miRNAs for LUAD prognosis were screened by both Cox risk proportional regression model and Last Absolute Shrinkage and Selection Operator (LASSO) regression model. The performances of the models were verified by time-dependent Receiver Operating Characteristic (ROC) curve. The possible biological processes linked to the miRNAs' target genes were analyzed by Gene Ontology (GO), Kyoto gene and genome encyclopedia (KEGG).

RESULTS

Among 127 differentially expressed miRNAs identified from the screening analysis, there are 111 up-regulated and 16 down-regulated miRNAs. Three of them, hsa-miR-1293, hsa-miR-490 and hsa-miR- 5571, were also significantly associated with the survival of the LUAD patients. The targets of the three miRNAs are significantly enriched in systemic lupus erythematosus pathways.

CONCLUSION

Hsa-miR-1293, hsa-miR-490 and hsa-miR-5571 can be potentially used as novel biomarkers for the prognosis prediction of LUAD.

KH-Domain Poly(C)-Binding Proteins as Versatile Regulators of Multiple Biological Processes

Five known members of the family of KH-domain poly(C)-binding proteins (Pcbp1-4, hnRNP-K) have an unusually broad spectrum of cellular functions that include regulation of gene transcription, regulation of pre-mRNA processing, splicing, mRNA stability, translational silencing and enhancement, the control of iron turnover, and many others. Mechanistically, these proteins act via nucleic acid binding and protein-protein interactions. Through performing these multiple tasks, the KH-domain poly(C)-binding family members are involved in a wide variety of biological processes such as embryonic development, cell differentiation, and cancer. Deregulation of KH-domain protein expression is frequently associated with severe developmental defects and neoplasia. This review summarizes progress in studies of the KH-domain proteins made over past two decades. The review also reports our recent finding implying an involvement of the KH-factor Pcbp1 into control of transition from naïve to primed pluripotency cell state.

Polycomb complex mediated epigenetic reprogramming alters TGF-β signaling via a novel EZH2/miR-490/TGIF2 axis thereby inducing migration and EMT potential in glioblastomas

Recent advancement in understanding cancer etiology has highlighted epigenetic deregulation as an important phenomenon leading to poor prognosis in glioblastoma (GBM). Polycomb repressive complex 2 (PRC2) is one such important epigenetic modifier reportedly altered in GBM. However, its defined mechanism in tumorigenesis still remains elusive. In present study, we analyzed our in-house ChIPseq data for H3k27me3 modified miRNAs and identified miR-490-3p to be the most common target in GBM with significantly downregulated expression in glioma patients in both TCGA and GBM patient cohort. Our functional analysis delineates for the first time, a central role of PRC2 catalytic unit EZH2 in directly regulating expression of this miRNA and its host gene CHRM2 in GBM. In accordance, cell line treatment with EZH2 siRNA and 5-azacytidine also confirmed its coregulation by CpG and histone methylation based epigenetic mechanisms. Furthermore, induced overexpression of miR-490-3p in GBM cell lines significantly inhibited key hallmarks including cellular proliferation, colony formation and spheroid formation, as well as epithelial-to-mesenchymal transition (EMT), with downregulation of multiple EMT transcription factors and promigratory genes (MMP9, CCL5, PIK3R1, ICAM1, ADAM17 and NOTCH1). We also for the first time report TGFBR1 and TGIF2 as two direct downstream effector targets of miR-490-3p that are also deregulated in GBM. TGIF2, a novel target, was shown to promote migration and EMT that could partially be rescued by miR-490-3p overexpression. Overall, this stands as a first study that provides a direct link between epigenetic modulator EZH2 and oncogenic TGF-β signaling involving novel miR-490-3p/TGIF2/TGFBR1 axis, that being targetable might be promising in developing new therapeutic intervention strategies for GBM.

MicroRNAs as Potential Targets for Therapeutic Intervention With Metastasis of Non-small Cell Lung Cancer

The death toll of non-small cell lung cancer (NSCLC) patients is primarily due to metastases, which are poorly amenable to therapeutic intervention. In this review we focus on miRs associated with metastasis of NSCLC as potential new targets for anti-metastatic therapy. We discuss miRs validated as therapeutic targets by in vitro data, identification of target(s) and pathway(s) and in vivo efficacy data in at least one clinically-relevant metastasis-related model. A few of the discussed miRs correlate with the clinical status of NSCLC patients. Using miRs as therapeutic agents has the advantage that targeting a single miR can potentially interfere with several metastatic pathways. Depending on their mode of action, the corresponding miRs can be up- or down-regulated compared to normal matching tissues. Here, we describe therapeutic approaches for reconstitution therapy and miR inhibition, general principles of anti-metastatic therapy as well as current technical pitfalls.

MicroRNA in Lung Cancer Metastasis

Tumor metastasis is a hallmark of cancer, with distant metastasis frequently developing in lung cancer, even at initial diagnosis, resulting in poor prognosis and high mortality. However, available biomarkers cannot reliably predict cancer spreading sites. The metastatic cascade involves highly complicated processes including invasion, migration, angiogenesis, and epithelial-to-mesenchymal transition that are tightly controlled by various genetic expression modalities along with interaction between cancer cells and the extracellular matrix. In particular, microRNAs (miRNAs), a group of small non-coding RNAs, can influence the transcriptional and post-transcriptional processes, with dysregulation of miRNA expression contributing to the regulation of cancer metastasis. Nevertheless, although miRNA-targeted therapy is widely studied in vitro and in vivo, this strategy currently affords limited feasibility and a few miRNA-targeted therapies for lung cancer have entered into clinical trials to date. Advances in understanding the molecular mechanism of metastasis will thus provide additional potential targets for lung cancer treatment. This review discusses the current research related to the role of miRNAs in lung cancer invasion and metastasis, with a particular focus on the different metastatic lesions and potential miRNA-targeted treatments for lung cancer with the expectation that further exploration of miRNA-targeted therapy may establish a new spectrum of lung cancer treatments.

A microRNA profile of pediatric glioblastoma: The role of NUCKS1 upregulation

MicroRNAs (miRNAs/miRs) are a novel class of gene regulators that may be involved in tumor chemoresistance. Recently, specific miRNA expression profiles have been identified in adult glioblastoma (aGBM), but there are only limited data available on the role of miRNAs in pediatric GBM (pGBM). In the present study, the expression profile of miRNAs was examined in seven pGBMs and three human GBM cell lines (U87MG, A172 and T98G), compared with a non-tumoral pool of pediatric cerebral cortex samples by microarray analysis. A set of differentially expressed miRNAs was identified, including miR-490, miR-876-3p, miR-876-5p, miR-448 and miR-137 (downregulated), as well as miR-501-3p (upregulated). Through bioinformatics analysis, a series of target genes was predicted. In addition, similar gene expression patterns in pGBMs and cell lines was confirmed. Of note, drug resistant T98G cells had upregulated nuclear casein kinase and cyclin-dependent kinase substrate 1 (NUCKS1) expression, a protein overexpressed in many tumors that serves an important role in cell proliferation and progression. On the basis of the present preliminary report, it could be intriguing to further investigate the relationship between each of the identified differentially expressed miRNAs and NUCKS1, in order to clarify their involvement in the multi-drug resistance mechanism of pGBMs.

Epigenetic predictive biomarkers for response or outcome to platinum-based chemotherapy in non-small cell lung cancer, current state-of-art

Platinum-based chemotherapy is commonly used to treat non-small cell lung cancer (NSCLC). However, its efficacy is limited and no molecular biomarkers that predict response are available. In this review, we summarize current knowledge concerning potential epigenetic predictive markers for platinum-based chemotherapy response in NSCLC. A systematic search of PubMed and ClinicalTrials.gov using keywords "non-small cell lung cancer" combined with "chemotherapy predictive biomarkers", "chemotherapy epigenetics biomarkers", "chemotherapy microRNA biomarkers", "chemotherapy DNA methylation" and "chemotherapy miRNA biomarkers" revealed 1740 articles from PubMed and 36 clinical trials. Finally, 22 papers and no trials fulfilled the review criteria. Among miRNA, combination of miR-1290, miR-196b and miR-135a in tumor tissue, and miR-21, miR-25, miR27b, and miR-326 in plasma were predictive for response to platinum-based chemotherapy in advanced NSCLC. RASSF1A methylation measured in tumor or blood was predictive for response to neoadjuvant chemotherapy. These biomarkers remain experimental and none have been tested in a prospective trial.

MiR-490-5p inhibits the metastasis of hepatocellular carcinoma by down-regulating E2F2 and ECT2

We intended to evaluate miR-490-5p expression in hepatocellular carcinoma (HCC) tissues and detect the potential targets of miR-490-5p. In vitro experiments were conducted to further investigate the biological function of miR-490-5p on HCC cell metastasis. We investigated the abnormally expressed miRNAs in HCC tissues, and the miR-490-5p expression level was detected by qRT-PCR. E2F2 and ECT2 were proved to be the potential targets of miR-490-5p by luciferase reporter assay. The expression levels of E2F2 and ECT2 were determined using Western blot. Transwell assay was used to analyse the impact of miR-490-5p on metastasis of HCC cells. Four high-expressed miRNAs, and seven low-expressed miRNAs, including miR-490-5p, were detected in HCC tissues. The expression level of miR-490-5p was connected with the tumor size, tumor node metastasis (TNM) stage, and survival ratio of HCC patients. E2F2 and ECT2 were the targets of miR-490-5p, and miR-490-5p inhibited HCC cell metastasis through down-regulating the expressions of E2F2 and ECT2. The over-expressed miR-490-5p could restrain the metastasis of HCC cells by down-regulating E2F2 and ECT2 expression levels.

MiR-490-3p Functions As a Tumor Suppressor by Inhibiting Oncogene VDAC1 Expression in Colorectal Cancer

Colorectal cancer (CRC) is one of the most common cancers worldwide, usually with poor prognosis because many CRC patients are diagnosed at an advanced stage. Therefore, novel potential diagnostic and prognostic biomarkers are urgently needed. MicroRNAs have been reported to regulate a variety of biological processes, such as cell proliferation, differentiation and apoptosis. Accumulating studies have demonstrated that miR-490-3p could regulate the development and progression of multiple cancers, but its clinical significance and molecular mechanism in CRC are still elusive. Here, we try to further elucidate the regulatory mechanism of miR-490-3p in CRC. In the present study, miR-490-3p expression level observably down-regulated in CRC tissues and cell lines, and miR-490-3p expression in CRC tissues was significantly associated with TNM stage, histological grade, tumor size and overall survival (OS). In addition, we observed miR-490-3p expression was also decreased in CRC plasmas and could act as a promising diagnostic biomarker for screening CRC. Further studies in vitro demonstrated Voltage Dependent Anion Channel 1 (VDAC1) which highly expressed in CRC tissues and cell lines is a direct target of miR-490-3p, and miR-490-3p could markedly inhibit CRC cells proliferation, metastasis, invasion and anti-apoptosis through suppressing VDAC1/AMPK/mTOR pathway. These results indicated that miR-490-3p functions as a tumor suppressor in CRC, and may be a novel potential diagnostic and prognostic biomarker for CRC.

Epithelial-to-Mesenchymal Transition and MicroRNAs in Lung Cancer

Despite major advances, non-small cell lung cancer (NSCLC) remains the major cause of cancer-related death in developed countries. Metastasis and drug resistance are the main factors contributing to relapse and death. Epithelial-to-mesenchymal transition (EMT) is a complex molecular and cellular process involved in tissue remodelling that was extensively studied as an actor of tumour progression, metastasis and drug resistance in many cancer types and in lung cancers. Here we described with an emphasis on NSCLC how the changes in signalling pathways, transcription factors expression or microRNAs that occur in cancer promote EMT. Understanding the biology of EMT will help to define reversing process and treatment strategies. We will see that this complex mechanism is related to inflammation, cell mobility and stem cell features and that it is a dynamic process. The existence of intermediate phenotypes and tumour heterogeneity may be debated in the literature concerning EMT markers, EMT signatures and clinical consequences in NSCLC. However, given the role of EMT in metastasis and in drug resistance the development of EMT inhibitors is an interesting approach to counteract tumour progression and drug resistance. This review describes EMT involvement in cancer with an emphasis on NSCLC and microRNA regulation.

microRNA-605 promotes cell proliferation, migration and invasion in non-small cell lung cancer by directly targeting LATS2

Lung cancer is the most common cause of cancer- associated mortality for men and women worldwide. An increasing number of studies have reported that the abnormal expression of microRNAs contributes to the pathogenesis of the majority of human cancer types, including non-small cell lung cancer (NSCLC). The present study aimed to measure microRNA-650 (miR-650) expression in NSCLC and evaluate its function in NSCLC cells. Reverse transcription-quantitative polymerase chain reaction was used to determine miR-650 expression in NSCLC tissue samples and cell lines. Assays for cell proliferation, migration and invasion were performed to investigate the roles of miR-650 on NSCLC progression. Furthermore, the mechanisms underlying the effects of miR-650 on NSCLC cell growth and metastasis were determined. In the current study, miR-650 was demonstrated to be highly expressed in NSCLC tissue samples and cell lines. Inhibition of expression of miR-650 suppressed NSCLC cell proliferation, migration and invasion in vitro. Additionally, large tumor suppressor kinase 2 (LATS2) was identified as a direct target gene of miR-650 in NSCLC. LATS2 was revealed to be significantly downregulated in NSCLC tissues and was negatively correlated with miR-650 expression. Notably, LATS2 re-expression decreased NSCLC cell proliferation, migration and invasion; similar to the effects induced by miR-650 underexpression. In conclusion, the results of the current study suggest that miR-650 may serve as an oncogene by direct targeting LATS2 in NSCLC formation and progression.

Integrative analysis for identification of shared markers from various functional cells/tissues for rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic autoimmune disease. So far, it is unclear whether there exist common RA-related genes shared in different tissues/cells. In this study, we conducted an integrative analysis on multiple datasets to identify potential shared genes that are significant in multiple tissues/cells for RA. Seven microarray gene expression datasets representing various RA-related tissues/cells were downloaded from the Gene Expression Omnibus (GEO). Statistical analyses, testing both marginal and joint effects, were conducted to identify significant genes shared in various samples. Followed-up analyses were conducted on functional annotation clustering analysis, protein-protein interaction (PPI) analysis, gene-based association analysis, and ELISA validation analysis in in-house samples. We identified 18 shared significant genes, which were mainly involved in the immune response and chemokine signaling pathway. Among the 18 genes, eight genes (PPBP, PF4, HLA-F, S100A8, RNASEH2A, P2RY6, JAG2, and PCBP1) interact with known RA genes. Two genes (HLA-F and PCBP1) are significant in gene-based association analysis (P = 1.03E-31, P = 1.30E-2, respectively). Additionally, PCBP1 also showed differential protein expression levels in in-house case-control plasma samples (P = 2.60E-2). This study represented the first effort to identify shared RA markers from different functional cells or tissues. The results suggested that one of the shared genes, i.e., PCBP1, is a promising biomarker for RA.