Comprehensive landscape of extracellular vesicle-derived RNAs in cancer initiation, progression, metastasis and cancer immunology.

Extracellular vesicles (EVs), a class of heterogeneous membrane vesicles, are generally divided into exosomes and microvesicles on basis of their origination from the endosomal membrane or the plasma membrane, respectively. EV-mediated bidirectional communication among various cell types supports cancer cell growth and metastasis. EVs derived from different cell types and status have been shown to have distinct RNA profiles, comprising messenger RNAs and non-coding RNAs (ncRNAs). Recently, ncRNAs have attracted great interests in the field of EV-RNA research, and growing numbers of ncRNAs ranging from microRNAs to long ncRNAs have been investigated to reveal their specific functions and underlying mechanisms in the tumor microenvironment and premetastatic niches. Emerging evidence has indicated that EV-RNAs are essential functional cargoes in modulating hallmarks of cancers and in reciprocal crosstalk within tumor cells and between tumor and stromal cells over short and long distance, thereby regulating the initiation, development and progression of cancers. In this review, we discuss current findings regarding EV biogenesis, release and interaction with target cells as well as EV-RNA sorting, and highlight biological roles and molecular mechanisms of EV-ncRNAs in cancer biology.

Sulforaphane Attenuates Muscle Inflammation in Dystrophin-deficient mdx Mice via NF-E2-related Factor 2 (Nrf2)-mediated Inhibition of NF-κB Signaling Pathway.

Inflammation is widely distributed in patients with Duchenne muscular dystrophy and ultimately leads to progressive deterioration of muscle function with chronic muscle damage, oxidative stress, and reduced oxidative capacity. NF-E2-related factor 2 (Nrf2) plays a critical role in defending against inflammation in different tissues via activation of phase II enzyme heme oxygenase-1 and inhibition of the NF-κB signaling pathway. However, the role of Nrf2 in the inflammation of dystrophic muscle remains unknown. To determine whether Nrf2 may counteract inflammation in dystrophic muscle, we treated 4-week-old male mdx mice with the Nrf2 activator sulforaphane (SFN) by gavage (2 mg/kg of body weight/day) for 4 weeks. The experimental results demonstrated that SFN treatment increased the expression of muscle phase II enzyme heme oxygenase-1 in an Nrf2-dependent manner. Inflammation in mice was reduced by SFN treatment as indicated by decreased infiltration of immune cells and expression of the inflammatory cytokine CD45 and proinflammatory cytokines tumor necrosis factor-α, interleukin-1ß, and interleukin-6 in the skeletal muscles of mdx mice. In addition, SFN treatment also decreased the expression of NF-κB(p65) and phosphorylated IκB kinase-α as well as increased inhibitor of κB-α expression in mdx mice in an Nrf2-dependent manner. Collectively, these results show that SFN-induced Nrf2 can alleviate muscle inflammation in mdx mice by inhibiting the NF-κB signaling pathway.

Long noncoding RNA XIST acts as an oncogene in non-small cell lung cancer by epigenetically repressing KLF2 expression.

Recently, long noncoding RNAs (lncRNAs) have been identified as critical regulators in numerous types of cancers, including non-small cell lung cancer (NSCLC). X inactivate-specific transcript (XIST) has been found to be up-regulated and acts as an oncogene in gastric cancer and hepatocellular carcinoma, but little is known about its expression pattern, biological function and underlying mechanism in NSCLC. Here, we identified XIST as an oncogenic lncRNA by driving tumorigenesis in NSCLC. We found that XIST is over-expressed in NSCLC, and its increased level is associated with shorter survival and poorer prognosis. Knockdown of XIST impaired NSCLC cells proliferation, migration and invasion in vitro, and repressed the tumorigenicity of NSCLC cells in vivo. Mechanistically, RNA immune-precipitation (RIP) and RNA pull-down experiment demonstrated that XIST could simultaneously interact with EZH2 to suppress transcription of its potential target KLF2. Additionally, rescue experiments revealed that XIST's oncogenic functions were partly depending on silencing KLF2 expression. Collectively, our findings expound how XIST over-expression endows an oncogenic function in NSCLC.

FOXC1-mediated LINC00301 facilitates tumor progression and triggers an immune-suppressing microenvironment in non-small cell lung cancer by regulating the HIF1α pathway.

BACKGROUND: Long non-coding RNAs (lncRNAs) are extensively intricate in the tumorigenesis and metastasis of various cancer types. Nevertheless, the detailed molecular mechanisms of lncRNA in non-small cell lung cancer (NSCLC) still remain mainly undetermined. METHODS: qPCR was performed to verify LINC00301 expression in NSCLC clinical specimens or cell lines. Fluorescence in situ hybridization (FISH) was conducted to identify the localization of LINC00301 in NSCLC cells. Chromatin immunoprecipitation (ChIP) was subjected to validate the binding activity between FOXC1 and LINC00301 promoters. RNA immunoprecipitation (RIP) was performed to explore the binding activity between LINC00301 and EZH2. RNA pull-down followed by dot-blot, protein domain mapping, and RNA electrophoresis mobility shift assay (EMSA) were conducted to identify the detailed binding regions between LINC00301 and EZH2. Alpha assay was conducted to quantitatively assess the interaction between LINC00301 and EZH2. RESULTS: LINC00301 is highly expressed in NSCLC and closely corelated to its prognosis by analyzing the relationship between differentially expressed lncRNAs and prognosis in NSCLC samples. in vitro and in vivo experiments revealed that LINC00301 facilitates cell proliferation, releases NSCLC cell cycle arrest, promotes cell migration and invasion, and suppresses cell apoptosis in NSCLC. In addition, LINC00301 increases regulatory T cell (Treg) while decreases CD8+ T cell population in LA-4/SLN-205-derived tumors through targeting TGF-ß. The transcription factor FOXC1 mediates LINC00301 expression in NSCLC. Bioinformatics prediction and in vitro experiments indicated that LINC00301 (83-123 nucleotide [nt]) can directly bind to the enhancer of zeste homolog 2 (EZH2) (612-727 amino acid [aa]) to promote H3K27me3 at the ELL protein-associated factor 2 (EAF2) promoter. EAF2 directly binds and stabilizes von Hippel-Lindau protein (pVHL), so downregulated EAF2 augments hypoxia-inducible factor 1 α (HIF1α) expression by regulating pVHL in NSCLC cells. Moreover, we also found that LINC00301 could function as a competing endogenous RNA (ceRNA) against miR-1276 to expedite HIF1α expression in the cytoplasm of NSCLC cells. CONCLUSIONS: In summary, our present research revealed the oncogenic roles of LINC00301 in clinical specimens as well as cellular and animal experiments, illustrating the potential roles and mechanisms of the FOXC1/LINC00301/EZH2/EAF2/pVHL/HIF1α and FOXC1/LINC00301/miR-1276/HIF1α pathways, which provides novel insights and potential theraputic targets to NSCLC.

Expression and Prognosis Analyses of Runt-Related Transcription Factor Family in Human Leukemia.

Despite advances in early diagnosis and treatment, cancer remains the major reason for mortality worldwide. The Runt-related transcription factor (RUNX) family has been reported to participate in diverse human diseases. However, little is known about their expression and prognostic values in human leukemia. Herein, we conducted a detailed cancer versus normal analysis. The mRNA expression levels of the RUNX family in various kinds of cancers, including leukemia, were analyzed via the ONCOMINE and GEPIA (Gene Expression Profiling Interactive Analysis) databases. We observed that the mRNA expression levels of RUNX1, RUNX2, and RUNX3 were all increased in most cancers compared with normal tissues, especially in leukemia. Moreover, the expression levels of RUNX1, RUNX2, and RUNX3 are also highly expressed in almost all cancer cell lines, particularly in acute myeloid leukemia (AML) cell lines, analyzed by Cancer Cell Line Encyclopedia (CCLE) and European Bioinformatics Institute (EMBL-EBI) databases. Further, the LinkedOmics and GEPIA databases were used to evaluate the prognostic values. In survival analyses based on LinkedOmics, higher expression of RUNX1 and RUNX2 indicated a better overall survival (OS), but with no significance, whereas increased RUNX3 revealed a poor OS in leukemia. In addition, the GEPIA dataset was also used to perform survival analyses, and results manifested that the expression of RUNX1 and RUNX2 had no remarkable correction with OS in leukemia, but it showed highly expressed RUNX3 was significantly related with poor OS in leukemia. In conclusion, the RUNX family showed significant expression differences between cancer and normal tissues, especially leukemia, and RUNX3 could be a promising prognostic biomarker for leukemia.

MiRNA-based Therapeutic Strategy in Lung Cancer.

Lung cancer is one of the most common malignant tumors in the world. Although advanced therapies have been applied for the treatment of lung cancer, the prolongation of overall survival is limited due to treatment resistance. MicroRNAs (miRNAs) are a class of small non-coding, endogenous RNA molecules (about 19-23 nucleotides in length), which could regulate numerous human genes and play key roles in a variety of diseases. MiRNAs are dysregulated in lung cancer and participate in tumor initiation, development and drug resistance. Recent studies showed a new therapeutic strategy for cancer therapy based on miRNAs. In this review, we briefly summarize one classic pathway of miRNAs in lung cancer, and discuss a new miRNA-based therapeutic strategy to manage lung cancer.

Long intergenic non-protein coding RNA 319 aggravates lung adenocarcinoma carcinogenesis by modulating miR-450b-5p/EZH2.

Growing evidence shows that long non-coding RNAs (lncRNAs) have been wildly verified to modulate multiple tumorigenesis, especially lung adenocarcinoma. In present study, we aim to investigate the role of lncRNA LINC00319 in the lung adenocarcinoma carcinogenesis. We observed that increased expression of LINC00319 in lung adenocarcinoma tissues and cells in comparison to their corresponding controls. Moreover, the aberrant overexpression of LINC00319 indicated the poor prognosis of lung adenocarcinoma patients. Silence of LINC00319 was able to repress lung adenocarcinoma cell growth in vitro. Rescue assay was performed to further confirm that LINC00319 contributed to lung adenocarcinoma progression by regulating miR-450b-5p/EZH2 signal pathway. Taken together, our study discovered the oncogenic role of LINC00319 in clinical specimens and cellular experiments, showing the potential LINC00319/miR-450b-5p/EZH2 pathway. This results and findings provide a novel insight for lung adenocarcinoma tumorigenesis.

Long non coding RNA XIST as a prognostic cancer marker - A meta-analysis.

BACKGROUND: The X inactivate-specific transcript (XIST), derived from XIST gene, is aberrantly expressed in various cancers. High-expression of XIST is related to poor clinical outcome. This meta-analysis evaluated the potential role of XIST as novel predictor of prognosis in human cancer. MATERIALS AND METHODS: This meta-analysis collected eligible studies about XIST and tumor prognosis through retrieving keywords in Web of Science, PubMed, Embase and the CNKI database, from 1993 to August 21, 2017. The quantitative meta-analysis was carried out with Stata SE12.0 and RevMan3.23 software. The aim was to determine whether XIST expression is associated with cancer prognosis and clinicopathology. RESULTS: A total of 858 patients from 10 eligible studies were included in the final meta-analysis. Overall, a significant negative association between XIST and overall survival (OS) time (HR = 2.62, 95% CI: 2.18-3.14) was observed. Statistical significance was also showed in subgroup meta-analysis stratified by the country, sample size, follow-up and publication year. It was reported that increased XIST was positively related to advanced clinical TNM stage (OR = 4.03, 95% CI: 2.22-7.30), lymph node metastasis (LNM) (OR = 2.70, 95% CI: 1.73-4.21), distant metastasis (DM) (OR = 2.61, 95% CI: 1.57-4.33) and tumor size (OR = 3.10, 95% CI: 2.24-4.30). CONCLUSIONS: LncRNA XIST may serve as a potential biomarker to predict solid tumor prognosis. This molecule can be effectively used to predict the clinical and pathological features of cancers.

Emerging landscape of circular RNAs in lung cancer.

Lung cancer, the leading cause of cancer deaths worldwide, is characterized with malignant cell growth. Advances in next-generation sequencing has helped us further understand RNA and identify novel circular RNAs (circRNAs) that may be useful in the early diagnosis and treatment of lung cancer. Similar to other noncoding RNAs, circRNAs present diverse biological functions in normal and disease states, including various types of cancers. This review focuses mainly on the poorly understood functions of circRNA in lung cancer. This paper also summarizes the recent advances in circRNA biogenesis, analyzes the role of circRNAs in cancers, and discusses the potential mechanisms of circRNAs in lung cancer.

Transcriptional E2F1/2/5/8 as potential targets and transcriptional E2F3/6/7 as new biomarkers for the prognosis of human lung carcinoma.

E2F is a group of genes that encode a family of transcription factors (TFs) in higher eukaryotes and participate in cell cycle regulation and DNA synthesis in mammalian cells. Evidence from cell lines, mouse models, and human tissues indicates that TFs are implicated in lung cancer (LC) tumorigenesis. However, the diverse expression patterns and prognostic values of eight E2Fs have yet to be elucidated. In the current study, we examined the transcriptional and survival data of E2Fs in patients with LC from ONCOMINE, GEPIA, Kaplan-Meier Plotter, and cBioPortal databases. We found that the expression levels of E2F1/2/3/5/6/7/8 were higher in lung adenocarcinoma and squamous cell lung carcinoma tissues than in lung tissues, whereas the expression level of E2F4 was lower in the former than in the latter. The expression levels of E2F2/4/5/7/8 were correlated with advanced tumor stage. Survival analysis using the Kaplan-Meier Plotter database revealed that the high transcription levels of E2F1/2/4/5/7/8 were associated with low relapse-free survival (RFS) in all of the patients with LC. Conversely, high E2F3/6 levels predicted high RFS in these patients. This study implied that E2F3/6/7 are potential targets of precision therapy for patients with LC and that E2F1/2/4/5/8 are new biomarkers for the prognosis of LC.

miR-206/133b Cluster: A Weapon against Lung Cancer?

Lung cancer is a deadly disease that ends numerous lives around the world. MicroRNAs (miRNAs) are a group of non-coding RNAs involved in a variety of biological processes, such as cell growth, organ development, and tumorigenesis. The miR-206/133b cluster is located on the human chromosome 6p12.2, which is essential for growth and rebuilding of skeletal muscle. The miR-206/133b cluster has been verified to be dysregulated and plays a crucial role in lung cancer. miR-206 and miR-133b participate in lung tumor cell apoptosis, proliferation, migration, invasion, angiogenesis, drug resistance, and cancer treatment. The mechanisms are sophisticated, involving various target genes and molecular pathways, such as MET, EGFR, and the STAT3/HIF-1α/VEGF signal pathway. Hence, in this review, we summarize the role and potential mechanisms of the miR-206/133b cluster in lung cancer.

MicroRNAs: A novel potential biomarker for diagnosis and therapy in patients with non-small cell lung cancer.

BACKGROUND: Lung cancer is still one of the most serious causes of cancer-related deaths all over the world. MicroRNAs (miRNAs) are defined as small non-coding RNAs which could play a pivotal role in post-transcriptional regulation of gene expression. Increasing evidence demonstrated dysregulation of miRNA expression associates with the development and progression of NSCLC. AIMS: To emphasize a variety of tissue-specific miRNAs, circulating miRNAs and miRNA-derived exosomes could be used as potential diagnostic and therapeutic biomarkers in NSCLC patients. MATERIALS & METHODS: In the current review, we paid attention to the significant discoveries of preclinical and clinical studies, which performed on tissue-specific miRNA, circulating miRNA and exosomal miRNA. The related studies were obtained through a systematic search of Pubmed, Web of Science, Embase. RESULTS: A variety of tissue-specific miRNAs and circulating miRNAs with high sensitivity and specificity which could be used as potential diagnostic and therapeutic biomarkers in NSCLC patients. In addition, we emphasize that the miRNA-derived exosomes become novel diagnostic biomarkers potentially in these patients with NSCLC. CONCLUSION: MiRNAs have emerged as non-coding RNAs, which have potential to be candidates for the diagnosis and therapy of NSCLC.

Echinocystic acid ameliorates hyperhomocysteinemia-induced vascular endothelial cell injury through regulating NF-κB and CYP1A1.

The present study investigated the role of echinocystic acid (EA) on the expression of nuclear factor (NF)-κB and cytochrome P450 1A1 (CYP1A1), and aortic morphology, in a rat model of hyperhomocysteinemia (Hhcy). A total of 50 Sprague Dawley rats were randomly divided into five groups as follows: Normal control (NC), model control (MC), vitamin control (VC; folic acid 1 mg/kg + vitamin B2 2 mg/kg + vitamin B12 10u g/kg), EA1 (20 mg/kg EA) and EA2 (40 mg/kg EA). Plasma homocysteine (Hcy) levels were determined via high performance liquid chromatography, and the morphology of the aorta was investigated using hematoxylin and eosin staining. Furthermore, aortic mRNA and protein levels of NF-κB and CYP1A1 were measured using reverse transcription-quantitative polymerase chain reaction analysis and western blotting, respectively. Plasma Hcy levels, and aortic mRNA and protein levels of NF-κB and CYP1A1, were significantly lower in the EA-treated group compared with the MC group (all P<0.05). However, the aortic morphology remained normal, including the endothelial cells of the inner layer, and smooth muscle cells of the media layer and adventitia. In conclusion, the results of the present study indicate that EA has a protective role on vascular endothelial cells in Hhcy through decreasing plasma Hcy, and thus NF-κB and CYP1A1 expression.

The lncRNA PDIA3P Interacts with miR-185-5p to Modulate Oral Squamous Cell Carcinoma Progression by Targeting Cyclin D2.

Long noncoding RNAs (lncRNAs) are emerging as important regulators during tumorigenesis by serving as competing endogenous RNAs (ceRNAs). In this study, the qRT-PCR results indicated that the lncRNA protein disulfide isomerase family A member 3 pseudogene 1 (PDIA3P) was overexpressed in oral squamous cell carcinoma (OSCC) and decreased the survival rate of OSCC patients. CCK-8 and clonal colony formation assays were used to detect the effects of PDIA3P on proliferation. Results revealed that silencing PDIA3P by small interfering RNA (siRNA) inhibited OSCC cell proliferation and repressed tumor growth and reduced the expression of proliferation antigen Ki-67 in vivo. Furthermore, the interaction between PDIA3P and miRNAs was then analyzed by qRT-PCR and luciferase reporter gene assay. We found that PDIA3P negatively regulated miR-185-5p in OSCC cells. Simultaneously, we found that silencing PDIA3P by siRNA suppressed proliferation via miR-185-5p in OSCC cells. Moreover, silencing PDIA3P by siRNA inhibited CCND2 protein (no influence on mRNA levels) expression via miR-185-5p in OSCC cells, and CCND2 facilitated cell proliferation of SCC4 and SCC15 cells induced by sh-PDIA3P#1. Therefore, our study demonstrated that PDIA3P may be a therapeutic target for the treatment of OSCC.

miR-134: A Human Cancer Suppressor?

MicroRNAs (miRNAs) are small noncoding RNAs approximately 20-25 nt in length, which play crucial roles through directly binding to corresponding 3' UTR of targeted mRNAs. It has been reported that miRNAs are involved in numerous of diseases, including cancers. Recently, miR-134 has been identified to dysregulate in handles of human cancers, such as lung cancer, glioma, breast cancer, colorectal cancer, and so on. Increasing evidence indicates that miR-134 is essential for human carcinoma and participates in tumor cell proliferation, apoptosis, invasion and metastasis, drug resistance, as well as cancer diagnosis, treatment, and prognosis. Nevertheless, its roles in human cancer are still ambiguous, and its mechanisms are sophisticated as well, referring to a variety of targets and signal pathways, such as STAT5B, KRAS, MAPK/ERK signal pathway, Notch pathway, etc. Herein, we review the crucial roles of miR-134 in scores of human cancers via analyzing latest investigations, which might provide evidence for cancer diagnose, treatment, prognosis, or further investigations.

Hsa-miR-134 suppresses non-small cell lung cancer (NSCLC) development through down-regulation of CCND1.

Hsa-miRNA-134 (miR-134) has recently been discovered to have anticancer efficacy in different organs. However, the role of miR-134 on non-small cell lung cancer (NSCLC) is still ambiguous. In this study, we investigated the role of miR-134 on the development of NSCLC. The results indicated that miR-134 was significantly down-regulated in primary tumor tissues and very low levels were found in NSCLC cell lines. Ectopic expression of miR-134 in NSCLC cell lines significantly suppressed cell growth as evidenced by cell viability assay, colony formation assay and BrdU staining, through inhibition of cyclin D1, cyclin D2, CDK4 and up-regulation of p57(Kip2) and p21(Waf1/Cip1). In addition, miR-134 induced apoptosis, as indicated by concomitantly with up-regulation of key apoptosis protein cleaved caspase-3, and down-regulation of anti-apoptosis protein Bcl2. Moreover, miR-134 inhibited cellular migration and invasiveness through inhibition of matrix metalloproteinases (MMP)-7 and MMP-9. Further, oncogene CCND1 was revealed to be a putative target of miR-134, which was inversely correlated with miR-134 expression in NSCLC. Taken together, our results demonstrated that miR-134 played a pivotal role on NSCLC through inhibiting cell proliferation, migration, invasion, and promoting apoptosis by targeting oncogenic CCND1.