MicroRNA signatures in tumor tissue related to angiogenesis in non-small cell lung cancer

Exosomal MiR-199a-5p Inhibits Tumorigenesis and Angiogenesis by Targeting VEGFA in Osteosarcoma

Background

Osteosarcoma (OS) is the most common primary bone malignancy in children and adolescents. microRNAs have been found to play a vital role in tumor angiogenesis. Here, we investigated the effects of miR-199a-5p on tumor growth and angiogenesis in osteosarcoma. Furthermore, the underlying molecular mechanisms and signaling pathways were explored.

Methods

The datasets were extracted from the Gene Expression Omnibus and the differentially expressed miRNAs (DEmiRNAs) were screened out by the GEO2R online platform. The potential target genes were predicted using the miRTarBase database. The predicted target genes were further analyzed by Gene Ontology and pathway enrichment analysis and a regulatory network of DEmiRNAs and their target genes was constructed. In addition, the effects of osteosarcoma cell derived exosomal miR-199a-5p on the proliferation, migration and neovascularization of HUVECs were evaluated by conducting EdU assays, Transwell experiments and tube formation assays. A dual-luciferase reporter assay was performed to detect whether VEGFA was the direct target of miR-199a-5p. Furthermore, in vivo xenograft models were established to further investigate the intrinsic role of miR-199a-5p in osteosarcoma tumorigenesis and angiogenesis.

Results

A total of 149 DE-miRNAs were screened out, including 136 upregulated miRNAs and 13 downregulated miRNAs in human osteosarcoma plasma samples compared with normal plasma samples. A total of 1313 target genes of the top three upregulated and downregulated miRNAs were predicted. In the PPI network, the top 10 hub nodes with higher degrees were identified as hub genes, such as TP53 and VEGFA. By constructing the miRNA-hub gene network, we found that most of hub genes could be potentially modulated by miR-663a, miR-199a-5p and miR-223-3p. In addition, we found that the expression level of miR-199a-5p in exosomes derived from osteosarcoma cells was remarkably higher than the osteosarcoma cells, and the exosomes derived from osteosarcoma cells were transported to HUVECs. Overexpression of miR-199a-5p could significantly inhibited HUVEC proliferation, migration and neovascularization, whereas downregulation of miR-199a-5p expression exerted the opposite effect. Moreover, the in vivo results verified that overexpression of miR-199a-5p in osteosarcoma cells could suppress the growth and angiogenesis of tumors.

Conclusion

Our results demonstrated that miR-199a-5p could be transported from osteosarcoma cells to HUVECs through exosomes, subsequently targeting VEGFA and inhibiting the growth and angiogenesis of osteosarcoma. Therefore, miR-199a-5p may act as a biomarker in the diagnosis and treatment of osteosarcoma.

Circulating MicroRNA-21 and MicroRNA-122 as Prognostic Biomarkers in Hepatocellular Carcinoma Patients Treated with Transarterial Chemoembolization

BACKGROUND

MicroRNAs (miRNAs) have been proposed as biomarkers in hepatocellular carcinoma (HCC). We aim at evaluating miR-21 and miR-122 in HCC patients treated with drug-eluting beads transarterial chemoembolization (DEB-TACE) as prognostic biomarkers and investigating their correlation with hypoxia inducible factor-1α (HIF-1α) serum levels.

METHODS

In this retrospective study, 12 healthy subjects, 28 cirrhotics, and 54 HCC patients (tested before and four weeks after DEB-TACE) were included. Whole blood miR-21 and miR-122 levels were measured by quantitative real time (qRT)-PCR, while serum HIF-1α was assessed by an enzyme-linked immunosorbent assay (ELISA) test.

RESULTS

The highest level of miR-21 was found in cirrhotics, while HCC patients had the highest level of miR-122 (which was even higher in "viral" HCC, p = 0.006). miR-21 ratio (after/before DEB-TACE) and miR-122 below their respective cut-offs identified patients with longer progression-free survival (p = 0.0002 and p = 0.02, respectively). The combined assessment of alpha-fetoprotein and miR-21 ratio, both independent prognostic predictors, identified early progressors among patients with complete or partial radiological response. miR-21 levels positively correlated with HIF-1α before (p = 0.045) and after DEB-TACE (p = 0.035).

CONCLUSIONS

miR-21 ratio and miR-122 are useful prognostic markers after DEB-TACE. miR-21 correlates with HIF-1α and probably has a role in modulating angiogenesis in HCC.

Long intergenic noncoding RNA 00473 promoting migration and invasion of trophoblastic cell line HTR-8/SVneo via regulating miR-424-5p-mediated wnt3a/β-catenin signaling pathway

BACKGROUND

Preeclampsia (PE) is a serious obstetric complication. Recent studies point out that the functions of long intergenic noncoding RNA 00473 (linc00473), miR-424-5p, and Wnt/β-catenin signaling pathway were involved in the invasion and migration of extravillous trophoblast. Here, we investigated the role and mechanism of linc00473 in HTR-8/SVneo trophoblastic cell line and its role in PE.

METHOD

The expression levels of linc00473 and miR-424-5p in placental tissues and the transfection efficiency of miR-424-5p were detected by quantitative real-time polymerase chain reaction (qRT-PCR). HTR-8/SVneo cell invasion and proliferation were determined by transwell and Cell Counting Kit-8 (CCK-8) assays. The protein expressions of wnt3a, p-GSK3β, GSK3β, active β-catenin, and total β-catenin were detected by Western blot. The apoptosis and migration of HTR-8/SVneo cells were detected by flow cytometry and wound healing assays. The targeting relationships between linc00473, miR-424-5p, and wnt3a were predicted by ENCORI database and TargetScan V7.2 and were determined using dual-luciferase reporter assay.

RESULTS

The expression level of linc00473 was low and miR-424-5p was high in placenta of PE patients. Linc00473 can target miR-424-5p, while miR-424-5p target wnt3a. High expression of linc00473 and wnt3a promoted cell proliferation, migration, invasion, and inhibited cell apoptosis. However, miR-424-5p mimic inhibited HTR-8/SVneo cells proliferation, migration, invasion, while promoted cell apoptosis, partially reversed the effect of linc00473, while wnt3a overexpression partially counteracted the effect of miR-424-5p mimic.

CONCLUSION

Linc00473 mediates the regulation of Wnt/β-catenin signaling pathway by miR-424-5p to affect the invasion and migration ability of trophoblastic cell line HTR-8/SVneo. It indicated that linc00473 is involved in PE and could be a therapeutic target.

Epigenetic regulation of angiogenesis in lung cancer

Lung cancer is the leading cause of cancer-related deaths worldwide, in which angiogenesis is highly required for lung cancer cell growth and metastasis. Genetic regulation of this multistep process is being studied extensively, however, relatively less is known about the epigenetic regulation of angiogenesis in lung cancer. Several epigenetic alterations contribute to regulating angiogenesis, such as epimodifications of DNA, posttranslational modification of histones, and expression of noncoding RNAs. Here, we review the current knowledge of the epigenetic regulation of angiogenesis and discuss the potential clinical applications of epigenetic-based anticancer therapy in lung cancer. Overall, epigenetic-based therapy will likely emerge as a prominent approach to treat lung cancer in the future.

Circulating miR-21-5p and miR-126-3p: diagnostic, prognostic value, and multivariate analysis in non-small-cell lung cancer

One of the most recent of tumor molecular characterization approaches is the microRNA (miR) expression profile. No single marker is sufficiently accurate for clinical use. Numerous biomarkers panels were created for three main purposes: tumor subtype, classification and, early detection, and prediction of tumor responses to treatment and prognosis of patients. miR-21-5p and miR-126-3p have received special attention because of their relationship with many cancer sites such as lung cancer, colorectal cancer, and renal cell carcinoma. We aimed to study their diagnostic and prognostic utility in lung cancer patients. Serum carcinoembryonic antigen (CEA) level was measured using an enzyme-linked immunosorbent assay (ELISA) technique. The expression levels of miR-21-5p and miR-126-3p were determined by real-time PCR in 60 non small cell lung cancer (NSCLC) patients and 40 healthy controls to detect diagnostic utility. Moreover, it was correlated with all disease clinicopathological characters and patient survival. Higher miR-21-5p and lower miR-126-3p levels were found in lung cancer patients than in controls. The sensitivity of CEA and miR-21-5p and miR-126-3p were 78.3, 96.7, and 90% at cutoff points 7.5, 2.35, and 2.175, respectively to distinguish NSCLC patients from controls. On combining both miR-21-5p and miR-126-3p, an improvement of sensitivity to 97% was noted. For patients, miR-21-5P increased significantly with metastatic stage and the highest grade (GIII). There was significantly longer overall survival (OS) among patients with early stages, lower grades GI&II, low miR-21-5p, and high miR-126-3p. miR-126-3p and presence of metastasis, the last two factors were the independent factors affecting OS with a hazard ratio of 0.26 (95% CI: 0.06-1.09) and 3.64 (95% CI: 1.22-16.5), respectively. Circulating miR-21-5p and miR-126-3p may play a significant role in diagnosis and prognosis in NSCLC patients.

The role of HPV gene expression and selected cellular MiRNAs in lung cancer development

BACKGROUND

The high mortality rate of lung cancer can be justified that strong need to explore new aspect of tumor biology. Human papillomavirus (HPV) has been detected as risk factor for the development of lung cancer. The aim of this study was to determine the role of HPV and cellular/miRNAs genes expression in the epithelial-mesenchymal transition (EMT) and development of lung cancer.

METHODS

In this case-control study, 109 lung cancer tissue and 52 controls were included. We analyzed the presence of HPV infection, its genotypes (in positive samples) and the expression of viral genes (E2, E6 and E7). Also, We examined the expression of celluar factors including (a) p53 and retinoblastoma (Rb) (as anti-carcinogenic genes), (b) EMT related genes, (c) selected miRNAs.

RESULTS

Our results reported 51.4% and 23.1% of HPV genome in tumor tissues and control tissues samples, respectively. There was a significant association between the HPV positive status and lung cancer (OR = 3.26, 95% C.I = 1.47-7.02, P = 0.001). HPV type 16 was the most prevalent genotype in tissues. The expression of p53, RB, TIMP1, CCNG-1, E-cad and PTPN13 were decreased while MMP-2 and N-cad were increased in HPV-positive tumor/control tissues compared to HPV-negative tissues. Also, among miRNAs, let-7, miR-23, miR-34, miR-125, miR-146 were downregulated and miR-20, miR-424 were upregulated in HPV-positve tissues compared to HPV-negative tissues.

CONCLUSION

This study demonstrated that HPV infection and interaction with cellular genes and miRNAs promote EMT which involved in the lung cancer development.

Beyond Conventional: The New Horizon of Anti-Angiogenic microRNAs in Non-Small Cell Lung Cancer Therapy

GLOBOCAN 2018 identified lung cancer as the leading oncological pathology in terms of incidence and mortality rates. Angiogenesis is a key adaptive mechanism of numerous malignancies that promotes metastatic spread in view of the dependency of cancer cells on nutrients and oxygen, favoring invasion. Limitation of the angiogenic process could significantly hamper the disease advancement through starvation of the primary tumor and impairment of metastatic spread. This review explores the basic molecular mechanisms of non-small cell lung cancer (NSCLC) angiogenesis, and discusses the influences of the key proangiogenic factors-the vascular endothelial growth factor-A (VEGF-A), basic fibroblast growth factor (FGF2), several matrix metalloproteinases (MMPs-MMP-2, MMP-7, MMP-9) and hypoxia-and the therapeutic implications of microRNAs (miRNAs, miRs) throughout the entire process, while also providing critical reviews of a number of microRNAs, with a focus on miR-126, miR-182, miR-155, miR-21 and let-7b. Finally, current conventional NSCLC anti-angiogenics-bevacizumab, ramucirumab and nintedanib-are briefly summarized through the lens of evidence-based medicine.

Early diagnosis and screening in lung cancer

Lung cancer is the third most diagnosed cancer, but the first cause of cancer-related deaths worldwide. This rather high death rate is due mainly to the fact that most patients are diagnosed with advanced-stage cancer, for which the conventional treatment does not work. The most used screening method for lung cancer is a low-dose CT scan, but it is recommended for specific age populations and it also started different debates on its advantages for lung cancer diagnosis. Over the year, several new techniques have been developed that are less invasive, have lower side effect, and can be implemented at all types of populations. This article aimed to present the advantages and disadvantages of using several methods for lung cancer diagnosis, including analysis of volatile organic compounds, exhaled breath condensate analysis and specific genomic approaches.

Immune-related genes in tumor-specific CD4+ and CD8+ T cells in colon cancer

Background

Immune escape is an immunological mechanism underlying tumorigenesis, and T cells play an important role in this process. In this study, immune-related genes were evaluated in tumor-infiltrating CD4⁺ and CD8⁺ T cells in colon cancer.

Methods

ESTIMATE was used to calculate stromal and immune scores for tumor datasets downloaded from The Cancer Genome Atlas–Colon Cancer (COAD). Differentially expressed genes (DEGs) between samples with high and low stromal and immune scores were screened, followed by a functional enrichment analysis of the overlapping DEGs. The DEGs related to CD4⁺ and the CD8⁺ T cells were then screened. Predicted miRNA–mRNA and lncRNA–miRNA pairs were used to construct a competing endogenous RNA (ceRNA) network. Furthermore, chemical–gene interactions were predicted for genes in the ceRNA network. Kaplan–Meier survival curves were also plotted.

Results

In total, 83 stromal-related DEGs (5 up-regulated and 78 down-regulated) and 1270 immune-related DEGs (807 up-regulated and 293 down-regulated genes) were detected. The 79 overlapping DEGs were enriched for 39 biological process terms. Furthermore, 79 CD4⁺ T cell-related genes and 8 CD8⁺ T cell-related genes, such as ELK3, were screened. Additionally, ADAD1 and DLG3, related to CD4⁺ T cells, were significantly associated with the prognosis of patients with colon cancer. The chr22-38_28785274–29,006,793.1–miR-106a-5p-DDHD1 and chr22-38_28785274–29,006,793.1–miR-4319-GRHL1 axes obtained from CD4⁺ and CD8⁺ T cell-related ceRNAs were identified as candidates for further studies.

Conclusion

ELK3 is a candidate immune-related gene in colon cancer. The chr22-38_28785274–29,006,793.1–miR-106a-5p-DDHD1 and chr22-38_28785274–29,006,793.1–miR-4319-GRHL1 axes may be related to CD4⁺ and CD8⁺ T cell infiltration in colon cancer.

Tissue microRNAs in non-small cell lung cancer detected with a new kind of liquid bead array detection system

Background

Commonly used miRNA detection methods cannot be applied for high-throughput analyses. However, this study was aimed to performed a liquid bead array detection system (LBAS) to detect tissue 6 miRNAs in non-small cell lung cancer (NSCLC).

Methods

In this study, evaluation of LBAS was performed to observe the precision, specificity, limitation and stability. Then, a total of 52 primary NSCLC patients who received resection operation without preoperative radiotherapy and chemotherapy between June 2013 and March 2014 were selected, and then the total RNA of the tissues were extracted. We prepared six NSCLC-related miRNAs for LBAS. After optimization and evaluation, LBAS was verified by detecting the relative expression levels of 6 microRNAs in the pathological tissues and corresponding normal tissues of 52 NSCLC patients.

Results

The results of evaluation of LBAS showed that the Mean Fluorescence Intensity (MFI) of the reaction only added with chimeric probes and beads showed no significant change after 180 days (P > 0.05). And the intra-assay Coefficient of Variation (CV) was between 1.57 and 3.5%, while the inter-assay CV was between 4.24 and 11.27%, indicating this system was ideal for diagnostic reagents. In addition, only the beads corresponding to the additional miRNAs showed high MFIs from 8426 to 18,769, whereas the fluorescence values of the other beads were under background levels (MFIs = 20 to 55) in each reaction, indicating no cross reactivity among the miRNAs. The limit of detection of miR-21, miR-210, miR-125b, miR-155, miR-375, and miR-31 were 5.27, 1.39, 1.85, 2.01, 1.34, and 2.73 amol/μL, respectively, showing that the lowest detection limit of miRNA by this system was under pM level. Then, the relative expression levels of miR-21, miR-210, miR-125b, miR-155, miR-375, and miR-31 by using this system were significantly correlated with NSCLC (P < 0.05). And the results of AUC method indicated that specific of the LBAS system was 94.2%.

Conclusions

Our findings suggest that LBAS was simple, high-throughput, and freely combined with absolute quantification. Thus, this system could be applied for tumor miRNAs detection.

Saikosaponin d downregulates microRNA-155 and upregulates FGF2 to improve depression-like behaviors in rats induced by unpredictable chronic mild stress by negatively regulating NF-κB

Saikosaponin d (SSd) is a traditional Chinese medicine that has been widely used in depression treatment. Given the lack of studies demonstrating the underlying mechanism of action of SSd in depression, the presented study was conducted with aims of investigating the effect of SSd on rats with depression-like behaviors induced by unpredicted chronic mild stress (UCMS) and its underlying molecular mechanism. To investigate the effect of SSd on depression, rat models with depression-like behaviors were established through 3-week exposure to UCMS, followed by administration of 10 mg/kg fluoxetine, 0.75 mg/kg SSd, 1.50 mg/kg SSd, or 10 mg/kg caffeic acid phenethyl ester (CAPE). The depression-like behaviors of rats were evaluated by sucrose preference test, open field test, forced swimming test, and tail suspension test. Afterwards, the regulatory relationship among nuclear factor-κB (NF-κB), microRNA (miR)-155 and fibroblast growth factor 2 (FGF2) were detected by dual-luciferase reporter gene assay and ChIP. RT-qPCR and Western blot analysis was conducted to determine the expression of genes and proteins. Finally, hippocampal neurons were extracted from modeled rats and transfected with miR-155 mimic, miR-155 inhibitor, NF-κB overexpression plasmid, or siRNA against NF-κB. The results showed that the depression-like behaviors induced by UCMS in rats was successfully attenuated by SSd. In hippocampal neurons of rats treated with SSd, NF-κB was significantly downregulated while FGF2 was significantly upregulated. NF-κB targets miR-155 and negatively regulates the expression of FGF2. NF-κB knockdown resulted in reduced depression-like behaviors of rats. These findings provide evidence that SSd could ameliorate depression-like behaviors in the rats treated with UCMS by downregulating NF-κB and miR-155, and upregulating FGF2.

MicroRNA-204 as an Indicator of Severity of Pulmonary Hypertension in Children with Congenital Heart Disease Complicated with Pulmonary Hypertension

BACKGROUND The objective of this study was to investigate the changes and significance of microRNA-204 (miR-204) in children with congenital heart disease (CHD) complicated with pulmonary hypertension (PH). MATERIAL AND METHODS Fifty-two CHD patients with left-to-right shunt were divided into 3 groups according to preoperative pulmonary artery systolic pressure (PASP) detected by color Doppler echocardiography: a control group (PASP <30 mmHg), a mild PH group (PASP 30-49 mmHg), and a severe PH group (PASP >50 mmHg). Peripheral venous blood and supernatant were collected on an empty stomach at 1 h before surgery and 7 days after surgery. The expression of miR-204 in plasma was detected by RT-qPCR. RESULTS One hour before surgery and 7 days after surgery, plasma miR-204 expression was at a higher level than that in the mild PH group and higher than in the severe PH group. miR-204 expression in children in each group showed a decreasing trend after surgery. The mild PH and severe PH groups had lower plasma miR-204 expression and PASP after surgery than before surgery. In the mild PH and severe PH groups, plasma miR-204 expression was negatively correlated with PASP. In all 52 cases, plasma miR-204 expression was negatively correlated with PASP. CONCLUSIONS The plasma miR-204 expression in CHD children with PH was negatively correlated with the degree of PH, suggesting miR-204 may be involved in PH development, and miR-204 expression may be an indicator of PH severity.

MicroRNA Changes in Firefighters

Objectives:

Firefighters have elevated cancer incidence and mortality rates. MicroRNAs play prominent roles in carcinogenesis, but have not been previously evaluated in firefighters.

Methods:

Blood from 52 incumbent and 45 new recruit nonsmoking firefighters was analyzed for microRNA expression, and the results adjusted for age, obesity, ethnicity, and multiple comparisons.

Results:

Nine microRNAs were identified with at least a 1.5-fold significant difference between groups. All six microRNAs with decreased expression in incumbent firefighters have been reported to have tumor suppressor activity or are associated with cancer survival, and two of the three microRNAs with increased expression in incumbent firefighters have activities consistent with cancer promotion, with the remaining microRNA associated with neurological disease.

Conclusion:

Incumbent firefighters showed differential microRNA expression compared with new recruits, providing potential mechanisms for increased cancer risk in firefighters.

miR-424-5p represses the metastasis and invasion of intrahepatic cholangiocarcinoma by targeting ARK5

MicroRNAs (miRNAs) have been validated to play prominent roles in the occurrence and development of many kinds of malignant cancer. MiR-424-5p has been reported to participate in various tumors proliferation and metastasis as a suppressor. On the contrary, miR-424-5p would promote cell proliferation in some tumors. However, the expression of miR-424-5p in intrahepatic cholangiocarcinoma (ICC) is rarely reported and its mechanism remains unclear. Here, we discover that miR-424-5p is frequently downregulated in ICC tissues compared with adjacent normal tissues and in ICC cells. Over-expression of miR-424-5p significantly inhibits the invasion and migration of ICC cells in vitro. Importantly, miR-424-5p is found to be a suppressor of ARK5, by binding to 3'-UTR of ARK5 mRNA and then inhibiting mTOR phosphorylated, thus deregulating epithelial-mesenchymal transition (EMT) of ICC. Furthermore, ARK5 is found to play a role in ICC metastasis and regulating EMT. Knockdown of ARK5 inhibits invasion and migration of ICC, while the over-expression gives an opposite effect. Besides, high-expression of ARK5 is also associated with poor prognosis. In conclusion, our study reveals that miR-424-5p is critical to the invasion, migration and EMT progression in ICC cells. Targeting the pathway described here may be a novel approach to inhibit metastasis of ICC and the restoration of miR-424-5p expression may be a promising strategy for ICC therapy.

Early Epigenetic Markers for Precision Medicine

Over the last years, epigenetic changes, including DNA methylation and histone modifications detected in early tumorigenesis and cancer progression, have been proposed as biomarkers for cancer detection, tumor prognosis, and prediction to treatment response. Importantly for the clinical use of DNA methylation biomarkers, specific methylation signatures can be detected in many body fluids including serum/plasma samples. Several of these potential epigenetic biomarkers detected in women's cancers, colorectal cancers, prostate, pancreatic, gastric, and lung cancers are discussed. Studies conducted in breast cancer, for example, found that aberrant methylation detection of several genes in serum DNA and genome-wide epigenetic change could be used for early breast cancer diagnosis and prediction of breast cancer risk. In colorectal cancers, numerous studies have been conducted to identify specific methylation markers important for CRC detection and in fact clinical assays evaluating the methylation status of SEPT19 gene and vimentin, became commercially available. Furthermore, some epigenetic changes detected in gastric washes have been suggested as potential circulating noninvasive biomarkers for the early detection of gastric cancers. For the early detection of prostate cancer, few epigenetic markers have shown a better sensitivity and specificity than serum PSA, indicating that the inclusion of these markers together with current screening tools, could improve early diagnosis and may reduce unnecessary repeat biopsies. Similarly, in pancreatic cancers, abnormal DNA methylation of several genes including NPTX2, have been suggested as a diagnostic biomarker. Epigenetic dysregulation was also observed in several tumor suppressor genes and miRNAs in lung cancer patients, suggesting the important role of these changes in cancer initiation and progression. In conclusion, epigenetic changes detected in biological fluids could play an essential role in the early detection of several cancer types and this may have a great impact for the cancer precision medicine field.

The Roles of MicroRNA in Lung Cancer

Lung cancer is the most devastating malignancy in the world. Beyond genetic research, epigenomic studies—especially investigations of microRNAs—have grown rapidly in quantity and quality in the past decade. This has enriched our understanding about basic cancer biology and lit up the opportunities for potential therapeutic development. In this review, we summarize the involvement of microRNAs in lung cancer carcinogenesis and behavior, by illustrating the relationship to each cancer hallmark capability, and in addition, we briefly describe the clinical applications of microRNAs in lung cancer diagnosis and prognosis. Finally, we discuss the potential therapeutic use of microRNAs in lung cancer.

AngiomiRs: MicroRNAs driving angiogenesis in cancer (Review)

Angiogenesis is an important hallmark of cancer serving a key role in tumor growth and metastasis. Therefore, tumor angiogenesis has become an attractive target for development of novel drug therapies. An increased amount of anti‑angiogenic compounds is currently in preclinical and clinical development for personalized therapies. However, resistance to current angiogenesis inhibitors is emerging, indicating that there is a need to identify novel anti‑angiogenic agents. In the last decade, the field of microRNA biology has exploded revealing unsuspected functions in tumor angiogenesis. These small non‑coding RNAs, which have been dubbed as angiomiRs, may target regulatory molecules driving angiogenesis, such as cytokines, metalloproteinases and growth factors, including vascular endothelial growth factor, platelet‑derived growth factor, fibroblast growth factor, epidermal growth factor, hypoxia inducible factor‑1, as well as mitogen‑activated protein kinase, phosphoinositide 3‑kinase and transforming growth factor signaling pathways. The present review discusses the current progress towards understanding the functions of miRNAs in tumor angiogenesis regulation in diverse types of human cancer. Furthermore, the potential clinical application of angiomiRs towards anti‑angiogenic tumor therapy was explored.

MicroRNA-155 inversely correlates with esophageal cancer progression through regulating tumor-associated macrophage FGF2 expression

Esophageal cancer (EC) is one of the most common malignancies with high incidence and mortality. Tumor-associated macrophages (TAMs) in the tumor microenvironment have been linked to the accelerated tumor progression. MicroRNAs (miR) are 19-25 nucleotide-long, noncoding RNA molecules, functioning as modulators of gene expression, and mediate a variety of biological functions, including tumor growth. In the present study, the effects and molecular mechanism of miR-155 in TAMs isolated from EC were explored. The expression of miR-155 and fibroblast growth factor-2 (FGF2) in EC tissues and cell lines were analyzed using reverse transcription-quantitative PCR (qRT-PCR) and western blot assays. TAMs were also transfected with the described constructs. Following, the culture medium from TAMs was collected for further analysis. The released FGF2, and inflammatory cytokines were quantified using ELISA. The cell viability, migrated and invaded levels were calculated through Cell Counting kit-8 (CCK8), and transwell analysis. Moreover, human umbilical vein endothelial cells (HUVEC) vasculature formation was determined using matrigel angiogenesis analysis. The results indicated that miR-155 expression was decreased in EC tissues and cell lines, while FGF2 expression was increased in comparison to those in the normal control group. Moreover, miR-155 mimics transfection up-regulated tumor necrosis factor α (TNF-α), interleukin (IL)-12 and inducible nitric oxide synthase (iNOS), while down-regulated IL-10, Arginase-1 (Arg-1) and IL-22 levels in the culture medium from TAMs. And enhancing miR-155 expression in TAMs suppressed the cell viability, migration and invasion of ECA109 cells and reduced the angiogenesis. Nevertheless, over-expressing FGF2 abolished the role of miR-155 in cancer cell survival, migration, invasion as well as angiogenesis. Our findings indicated that miR-155-regulated FGF2 expression from TAMs suppressed EC cell proliferation, migration, invasion and inhibited vasculature formation. Thus, miR-155-modulated FGF2 might be a potential therapeutic target to prevent EC progression.

MiR-182 promotes glucose metabolism by upregulating hypoxia-inducible factor 1α in NSCLC cells

OBJECTIVE

This study aims to demonstrate the role of miR-182 in the glucose metabolism of NSCLC cells and the potential mechanism.

METHODS

MTT Cytotoxicity Assay was used to measure the function of differentially expressed miR-182 on two NSCLC cell lines proliferation. Metabolite analysis was introduced to monitor the glucose consumption, lactate release and glycolytic intermediate metabolites. The mRNA level of critical genes involved in glycolysis was detected by qRT-PCR. The 3'UTRs of predicted gene with a miR-182 binding site and their seed-sequence-mutated version were cloned downstream to the ORF of a Renilla luciferase reporter gene and the ability of miR-182 to downregulate luciferase expression was assessed.

RESULTS

MiR-182 had significantly improved proliferation of NSCLC cell lines. Metabolite analysis of the cells with strengthened miR-182 revealed significantly increased glucose consumption and lactate release, as well as glycolytic intermediate metabolites, or conversely. Among a panel of genes controlling glucose metabolism, miR-182 exhibited significantly influence on ENO1, GLUT1, HIF-1α, HK1, HK2, LDHA and PDK1, especially HIF-1α. For the predicted target gene HIF1AN, the wild-type but not mutated 3'UTR, responded to miR-182  b y directing ∼45% reduction of reporter gene expression.

CONCLUSION

MiR-182 promotes glucose metabolism by upregulating HIF-1α in NSCLC cells.

Highly expressed placental miRNAs control key biological processes in human cancer cell lines

Despite being a healthy tissue, the constituent cells of the placenta, share similar characteristics with tumor cells, such as increased cell growth, migration, and invasion. However, while these processes are stochastic and uncontrolled in cancer cells, in placenta they are precisely controlled. Since miRNAs have been reported to regulate genes that control the molecular mechanisms necessary for the development of both human placenta and cancer, we addressed for miRNAs highly expressed in the placenta that could be involved in tumorigenesis. Here, we assessed the miRNA profile in placenta samples using microarray analysis. The results showed that miR-451 and miR-720, highly expressed placental miRNAs, presented very low or undetectable expression in cancer cell lines compared to the normal placenta and healthy tissues. Additionally, transfection of miR-451 or miR-720 mimics in choriocarcinoma cell line (JEG3) and colorectal adenocarcinoma cell line (HT-29) resulted in impaired cell proliferation, decreased cell migration and invasion and reduced ability of colony formation. These findings provide evidence that placenta may work as an alternative model to identify novel miRNAs involved in pathways controlling tumorigenesis.

Imaging of angiogenesis of human umbilical vein endothelial cells by uptake of exosomes secreted from hepatocellular carcinoma cells

Hepatocellular carcinoma (HCC) is a typical hyper-vascular tumor, so the understanding the mechanisms of angiogenesis in HCC is very important for its treatment. However, the influence of the exosomes secreted from HCC cells (HCC-exosomes) on angiogenesis remains poorly understood. We herein examined the effects of the exosomes secreted from HepG2 cells (HepG2-exosomes) on the lumen formation of human umbilical vein endothelial cells (HUVECs) by the imaging of angiogenesis. The degree of lumen formation of HUVECs was dependent on the number of HepG2-exosomes. The HepG2-exosomes expressed NKG2D, an activating receptor for immune cells, and HSP70, a stress-induced heat shock protein associated with angiogenesis through the vascular endothelial growth factor (VEGF) receptor. In addition, the HepG2-exosomes contained several microRNAs (miRNAs) reported to exist in the serum of HCC patients. These results suggest that the HCC-exosomes play an important role in angiogenesis. Further studies on the function of HCC-exosomes may provide a new target for HCC treatment.

Non-small cell lung cancer associated microRNA expression signature: integrated bioinformatics analysis, validation and clinical significance

Recently, increasing studies of miRNA expression profiling has confirmed that miRNA plays an essential role in non-small cell lung cancer (NSCLC). However, inconsistent or discrepant results exist in these researches. In present study, we performed an integrative analysis of 32 miRNA profiling studies compared the differentially expressed miRNA between NSCLC tissue and non-cancerous lung tissue to identify candidate miRNAs associated with NSCLC. 7 upregulated and 10 downregulated miRNAs were identified as miRNA integrated-signature using Robust Rank Aggregation (RRA) method. qRT-PCR demonstrated that miR-21-5p, miR-210, miR-205-5p, miR-182-5p, miR-31-5p, miR-183-5p and miR-96-5p were up-regulated, whereas miR-126-3p, miR-30a-5p, miR-451a, miR-143-3p and miR-30d-5p were down-regulated more than 2 folds in the NSCLC, which was further validated in Tumor Cancer Genome Atlas (TCGA) database. Receiver operating characteristic (ROC) curve analysis confirmed that 9 miRNAs had good predictive performance (AUC > 0.9). Cox regression analysis revealed that miR-21-5p (hazard ratio [HR]: 1.616, 95% CI: 1.114–2.342, p = 0.011) and miR-30d-5p (HR: 0.578, 95% CI: 0.400–0.835, p = 0.003) were independent prognostic factors in NSCLC for overall survival. The accumulative effects of the two miRNAs on the prognosis of NSCLC were further estimated. The results showed that patients with two positive markers had a worse prognosis than those with one or none positive marker. In conclusion, this study contributes to the comprehension of the role of miRNAs in NSCLC and provides a basis for further clinical application.

miR-424-5p promotes proliferation of gastric cancer by targeting Smad3 through TGF-β signaling pathway

MiRNAs have been reported to regulate gene expression and be associated with cancer progression. Recently, miR-424-5p was reported to play important role in a variety of tumors. However, the role and molecular mechanisms of miR-424-5p in GC (gastric cancer) remains largely unknown. In this study, we aimed to explore the role of miR-424-5p in GC. QRT-PCR was used to determine the expression levels of miR-424-5p and Smad3. CCK8 assay, plate clone assay and cell cycle assay were used to measure the effects of miR-424-5p on GC cell proliferation. Luciferase reporter assay and western blotting were used to prove that Smad3 was one of the direct targets of miR-424-5p. Tumorigenesis assay was used to investigate the role of miR-424-5p in tumor growth of GC cells in vivo. We found that miR-424-5p was up-regulated in GC tissues and cells. Over-expression of miR-424-5p could promote the proliferation of GC cells. In addition, luciferase reporter assay and western blotting assay revealed that Smad3 was a direct target of miR-424-5p. Over-expression of Smad3 could partially reverse the effects of miR-424-5p on GC cell proliferation. Our study further revealed that miR-424-5p could inhibit TGF-β signaling pathway by Smad3.

Clinical Impact of microRNAs Associated With Cancer Stem Cells as a Prognostic Factor in Ovarian Carcinoma

Background: Ovarian carcinoma is a highly lethal gynecological malignancy due to its frequent relapses and adoption of chemoresistance. To develop new biomarkers for disease progression in ovarian carcinoma, CSCs, which are considered to contribute to disease relapse and metastasis, were isolated from human ovarian carcinoma tissues, and differentially expressed microRNAs (miRNAs) in CSCs were identified and assessed the clinical implication of expression of these miRNAs.

Methods: Primary cancer cells derived from human ovarian carcinomas were cultured and spheroid-forming cells (SFCs) were isolated. Profiles of miRNA expression in CSC-like SFCs were identified by miRNA microarray and the results were validated by quantitative real-time RT-PCR (qRT-PCR). We also assessed the correlations between miRNA expression levels and clinicopathological parameters in ovarian carcinomas.

Results: Five miRNAs (miR-5703, miR-630, miR-1246, miR-424-5p, and miR-320b) were significantly dysregulated in CSC-like SFCs compared with primary cancer cells. The qRT-PCR showed that miR-5703 and miR-1246 expression was significantly higher in ovarian cancer cells than in normal control cells, whereas the miR-424-5p level was significantly lower. Decreased expression of miR-424-5p was significantly associated with distant metastasis in high stage (stage IIII & IV) carcinomas (35.5% vs. 72.2%, respectively, p=0.013)

Conclusion: Taken together, miR-5703, miR-630, miR-1246, miR-424-5p, and miR-320b are useful markers for enriching ovarian CSCs. Decreased expression of miR-424-5p in ovarian carcinoma might be a putative biomarker for distant metastasis in ovarian carcinoma.

Analysis of microRNA (miRNA) expression profiles reveals 11 key biomarkers associated with non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer (NSCLC) accounts for more than 85% of lung cancer cases which cause most of cancer-related deaths globally. However, the results vary largely in different studies due to different platforms and sample sizes. Here, we aim to identify the key miRNAs in the carcinogenesis of NSCLC that might be potential biomarkers for this cancer.

METHODS

Meta-analysis was performed on miRNA profile using seven datasets of NSCLC studies. Furthermore, we predicted and investigated the functions of genes regulated by key miRNAs.

RESULTS

Eleven key miRNAs were identified, including 2 significantly upregulated ones (hsa-miR-21-5p and hsa-miR-233-3p) and 9 downregulated ones (hsa-miR-126-3p, hsa-miR-133a-3p, hsa-miR-140-5p, hsa-miR-143-5p, hsa-miR-145-5p, hsa-miR-30a-5p, hsa-miR-30d-3p, hsa-miR-328-3pn, and hsa-miR-451). The functional enrichment analysis revealed that both up- and downregulated miRNAs were proportionally associated with regulation of transcription from RNA polymerase II promoter. According to transcription factor analysis, there were 65 (43.9%) transcription factors influenced by both up- and downregulated miRNAs.

CONCLUSIONS

In this study, 11 meta-signature miRNAs, as well as their target genes and transcription factors, were found to play significant role in carcinogenesis of NSCLC. These target genes identified in our study may be profitable to diagnosis and prognostic prediction of NSCLC as biomarkers.

The expression and function of miR-424 in infantile skin hemangioma and its mechanism

Infantile hemangioma is the most common benign tumor in infants. Many studies have confirmed that basic fibroblast growth factor (bFGF) and its key receptor FGFR1 are highly expressed in hemangioma. Moreover, several miRNAs can regulate angiogenesis. In this regard, miR-424 often plays a role as tumor suppressor gene. This study was designed to investigate the mechanism of miR-424 in infantile skin hemangioma. Our results showed low expression of miR-424 in infantile skin hemangioma tissues, and that miR-424 overexpression downregulated FGFR1 expression in hemangioma-derived endothelial cells, while miR-424 inhibition upregulated FGFR1 expression. Luciferase reporter analysis confirmed that FGFR1 was a target gene of miR-424. CCK-8, flow cytometry, transwell migration and tube formation assays demonstrated that miR-424 overexpression inhibited cell proliferation, migration and tube formation, at least in part by blocking the bFGF/FGFR1 pathway. In contrast, miR-424 inhibition significantly enhanced these functions. Furthermore, miR-424 overexpression significantly inhibited ERK1/2 phosphorylation, whereas miR-424 inhibition enhanced ERK1/2 phosphorylation. In conclusion, miR-424 could suppress the bFGF/FGFR1 pathway, thereby inhibit ERK1/2 phosphorylation, and thus inhibit cell proliferation, migration and tube formation capabilities and the development of infantile skin hemangioma.

Identifying the miRNA signature associated with survival time in patients with lung adenocarcinoma using miRNA expression profiles

Lung adenocarcinoma is a multifactorial disease. MicroRNA (miRNA) expression profiles are extensively used for discovering potential theranostic biomarkers of lung cancer. This work proposes an optimized support vector regression (SVR) method called SVR-LUAD to simultaneously identify a set of miRNAs referred to the miRNA signature for estimating the survival time of lung adenocarcinoma patients using their miRNA expression profiles. SVR-LUAD uses an inheritable bi-objective combinatorial genetic algorithm to identify a small set of informative miRNAs cooperating with SVR by maximizing estimation accuracy. SVR-LUAD identified 18 out of 332 miRNAs using 10-fold cross-validation and achieved a correlation coefficient of 0.88 ± 0.01 and mean absolute error of 0.56 ± 0.03 year between real and estimated survival time. SVR-LUAD performs well compared to some well-recognized regression methods. The miRNA signature consists of the 18 miRNAs which strongly correlates with lung adenocarcinoma: hsa-let-7f-1, hsa-miR-16-1, hsa-miR-152, hsa-miR-217, hsa-miR-18a, hsa-miR-193b, hsa-miR-3136, hsa-let-7g, hsa-miR-155, hsa-miR-3199-1, hsa-miR-219-2, hsa-miR-1254, hsa-miR-1291, hsa-miR-192, hsa-miR-3653, hsa-miR-3934, hsa-miR-342, and hsa-miR-141. Gene ontology annotation and pathway analysis of the miRNA signature revealed its biological significance in cancer and cellular pathways. This miRNA signature could aid in the development of novel therapeutic approaches to the treatment of lung adenocarcinoma.

Endogenous microRNA-424 predicts clinical outcome and its inhibition acts as cancer suppressor in human non-small cell lung cancer

PURPOSE

We examined the expression, clinical correlation and functional mechanisms of endogenous microRNA-424 (miR-424) in human non-small cell lung cancer (NSCLC).

METHODS

Expression pattern of endogenous miR-424 was examined by qRT-PCR in clinical samples obtained from 233 NSCLC patients. Correlations between differential miR-424 expression level (low vs. high) and NSCLC patients' clinicopathological parameters or survival were statistically examined. In in vitro NSCLC H596 and SW900 cells, miR-424 was either upregulated or downregulation by lentiviral transduction. Their effects on cancer cell viability, proliferation, and cell-cycle transition were also examined.

RESULTS

MiR-424 expression was not different between NSCLC tumors and healthy lung tissues. However, it is much upregulated in NSCLC tumors associated with patients at advanced clinical stages. Statistical analyses demonstrated that high endogenous miR-424 expression in NSCLC tumors was significantly correlated with patients' advanced clinical stages, aggressive tumor metastasis, and short survival. In addition, Cox regression model predicted that endogenous miR-424 might be an independent prognostic marker in NSCLC. In in vitro NSCLC cell lines, miR-424 downregulation had a significant suppressing effect on cancer proliferation and G1 to S phase cell-cycle transition. On the other hand, miR-424 upregulation had no effect on NSCLC in vitro.

CONCLUSION

High endogenous miR-424 expression in tumors may predict poor prognosis of patients with NSCLC. Inhibiting endogenous miR-424 may also serve an effective cancer suppressor in NSCLC.

MicroRNA-210 promotes cancer angiogenesis by targeting fibroblast growth factor receptor-like 1 in hepatocellular carcinoma

Hypoxia drives cancer to become more aggressive, particularly angiogenesis, and the corresponding mechanisms still need to be further investigated. In hepatocellular carcinoma (HCC), the master hypoxia-induced microRNA (miRNA) miR-210 is upregulated in HCC and participates in HCC progression, but its roles in hypoxia-induced HCC angiogenesis are still unknown. Moreover, the correlation between miR-210 expression and HCC clinical progression also needs elucidation. In the present study, we found that miR-210 expression was progressively increased from normal liver and adjacent non-tumor tissues, to incipient and advanced tumor tissues. In HCC patients, high miR-210 expression was significantly correlated with poor prognosis, both tumor-free survival and overall survival. Moreover, miR-210 expression in HCC was significantly positively correlated with microvascular density. Both in vitro and in vivo studies determined that miR-210 promoted HCC angiogenesis, and the corresponding mechanism was identified to be the direct targeting and inhibition of fibroblast growth factor receptor-like 1 (FGFRL1) expression. Thus, we suggest a new prognosis predictor for HCC patients, and determined the roles of hypoxic miR-210 in HCC angiogenesis.

Developmental transcription factor NFIB is a putative target of oncofetal miRNAs and is associated with tumour aggressiveness in lung adenocarcinoma

Genes involved in fetal lung development are thought to play crucial roles in the malignant transformation of adult lung cells. Consequently, the study of lung tumour biology in the context of lung development has the potential to reveal key developmentally relevant genes that play critical roles in lung cancer initiation/progression. Here, we describe for the first time a comprehensive characterization of miRNA expression in human fetal lung tissue, with subsequent identification of 37 miRNAs in non-small cell lung cancer (NSCLC) that recapitulate their fetal expression patterns. Nuclear factor I/B (NFIB), a transcription factor essential for lung development, was identified as a potential frequent target for these 'oncofetal' miRNAs. Concordantly, analysis of NFIB expression in multiple NSCLC independent cohorts revealed its recurrent underexpression (in ∼40-70% of tumours). Interrogation of NFIB copy number, methylation, and mutation status revealed that DNA level disruption of this gene is rare, and further supports the notion that oncofetal miRNAs are likely the primary mechanism responsible for NFIB underexpression in NSCLC. Reflecting its functional role in regulating lung differentiation, low expression of NFIB was significantly associated with biologically more aggressive subtypes and, ultimately, poorer survival in lung adenocarcinoma patients. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Deep sequencing reveals microRNAs predictive of antiangiogenic drug response

The majority of metastatic renal cell carcinoma (RCC) patients are treated with tyrosine kinase inhibitors (TKI) in first-line treatment; however, a fraction are refractory to these antiangiogenic drugs. MicroRNAs (miRNAs) are regulatory molecules proven to be accurate biomarkers in cancer. Here, we identified miRNAs predictive of progressive disease under TKI treatment through deep sequencing of 74 metastatic clear cell RCC cases uniformly treated with these drugs. Twenty-nine miRNAs were differentially expressed in the tumors of patients who progressed under TKI therapy (P values from 6 × 10^-9 to 3 × 10^-3). Among 6 miRNAs selected for validation in an independent series, the most relevant associations corresponded to miR-1307-3p, miR-155-5p, and miR-221-3p (P = 4.6 × 10^-3, 6.5 × 10^-3, and 3.4 × 10^-2, respectively). Furthermore, a 2 miRNA-based classifier discriminated individuals with progressive disease upon TKI treatment (AUC = 0.75, 95% CI, 0.64-0.85; P = 1.3 × 10^-4) with better predictive value than clinicopathological risk factors commonly used. We also identified miRNAs significantly associated with progression-free survival and overall survival (P = 6.8 × 10^-8 and 7.8 × 10^-7 for top hits, respectively), and 7 overlapped with early progressive disease. In conclusion, this is the first miRNome comprehensive study, to our knowledge, that demonstrates a predictive value of miRNAs for TKI response and provides a new set of relevant markers that can help rationalize metastatic RCC treatment.

IL-8 induces miR-424-5p expression and modulates SOCS2/STAT5 signaling pathway in oral squamous cell carcinoma

Suppressor of cytokine signaling (SOCS) proteins are negative feedback regulators of the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. Dysregulation of SOCS protein expression in cancers can be one of the mechanisms that maintain STAT activation, but this mechanism is still poorly understood in oral squamous cell carcinoma (OSCC). Here, we report that SOCS2 protein is significantly downregulated in OSCC patients and its levels are inversely correlated with miR‐424‐5p expression. We identified the SOCS2 protein, which modulates STAT5 activity, as a direct target of miR‐424‐5p. The miR‐424‐5p‐induced STAT5 phosphorylation, matrix metalloproteinases (MMPs) expression, and cell migration and invasion were blocked by SOCS2 restoration, suggesting that miR‐424‐5p exhibits its oncogenic activity through negatively regulating SOCS2 levels. Furthermore, miR‐424‐5p expression could be induced by the cytokine IL‐8 primarily through enhancing STAT5 transcriptional activity rather than NF‐κB signaling. Antagomir‐mediated inactivation of miR‐424‐5p prevented the IL‐8‐induced cell migration and invasion, indicating that miR‐424‐5p is required for IL‐8‐induced cellular invasiveness. Taken together, these data indicate that STAT5‐dependent expression of miR‐424‐5p plays an important role in mediating IL‐8/STAT5/SOCS2 feedback loop, and scavenging miR‐424‐5p function using antagomir may have therapeutic potential for the treatment of OSCC.

miR‐424‐5p is overexpressed in OSCC.

miR‐424‐5p directly targets SOCS2, leading to increased cell migration and invasion.

STAT5 activation is required for IL‐8‐mediated miR‐424‐5p transcription.

miR‐424‐5p plays an important role in mediating IL‐8/STAT5/SOCS2 feedback loop.

STAT3-regulated exosomal miR-21 promotes angiogenesis and is involved in neoplastic processes of transformed human bronchial epithelial cells

Although microRNA (miRNA) enclosed in exosomes can mediate intercellular communication, the roles of exosomal miRNA and angiogenesis in lung cancer remain unclear. We investigated functions of STAT3-regulated exosomal miR-21 derived from cigarette smoke extract (CSE)-transformed human bronchial epithelial (HBE) cells in the angiogenesis of CSE-induced carcinogenesis. miR-21 levels in serum were higher in smokers than those in non-smokers. The medium from transformed HBE cells promoted miR-21 levels in normal HBE cells and angiogenesis of human umbilical vein endothelial cells (HUVEC). Transformed cells transferred miR-21 into normal HBE cells via exosomes. Knockdown of STAT3 reduced miR-21 levels in exosomes derived from transformed HBE cells, which blocked the angiogenesis. Exosomes derived from transformed HBE cells elevated levels of vascular endothelial growth factor (VEGF) in HBE cells and thereby promoted angiogenesis in HUVEC cells. Inhibition of exosomal miR-21, however, decreased VEGF levels in recipient cells, which blocked exosome-induced angiogenesis. Thus, miR-21 in exosomes leads to STAT3 activation, which increases VEGF levels in recipient cells, a process involved in angiogenesis and malignant transformation of HBE cells. These results, demonstrating the function of exosomal miR-21 from transformed HBE cells, provide a new perspective for intervention strategies to prevent carcinogenesis of lung cancer.

Biomarkers in early-stage non-small-cell lung cancer: current concepts and future directions

Advances in molecular biology and bioinformatics have resulted in the identification of a number of potential biomarkers that could be relevant in the management of patients with non-small-cell lung cancer (NSCLC). Although there is an increasing amount of literature related to these biomarkers, major issues need to be resolved including validity and reproducibility of results. Additionally, in order to interpret the existing literature accurately, a clear distinction must be made between the prognostic and predictive value of biomarkers. The practical applicability of biomarker discovery for patients with lung cancer includes the identification of patients with early-stage NSCLC who are most likely to benefit from adjuvant therapy. Information gleaned from biomarkers has the potential to help in evaluating the role of targeted therapies including immunotherapy in the neoadjuvant and adjuvant setting. The role of gene signatures and the use of newer platforms such as RNA, methylation, and protein signatures is being explored in patients with early-stage NSCLC. This review focuses on the applications of biomarker discovery in patients with early-stage NSCLC.

CARMA3 Represses Metastasis Suppressor NME2 to Promote Lung Cancer Stemness and Metastasis

RATIONALE

CARD-recruited membrane-associated protein 3 (CARMA3) is a novel scaffold protein that regulates nuclear factor (NF)-κB activation; however, the underlying mechanism of CARMA3 in lung cancer stemness and metastasis remains largely unknown.

OBJECTIVES

To investigate the molecular mechanisms underlying the involvement of CARMA3 in non-small cell lung cancer progression.

METHODS

The expression levels of CARMA3 and NME2 in a cohort of patients with lung cancer (n = 91) were examined by immunohistochemistry staining and assessed by Kaplan-Meier survival analysis. The effects of CARMA3, microRNA-182 (miR-182), and NME2 on cancer stemness and metastasis were measured in vitro and in vivo. Chromatin immunoprecipitation and luciferase reporter assays were performed to determine the mechanisms of NF-κB-driven miR-182 expression and NME2 regulation.

MEASUREMENTS AND MAIN RESULTS

We observed that CARMA3 inversely correlated with NME2 expression in patients with lung cancer (Pearson correlation coefficient: R = -0.24; P = 0.022). NME2 levels were significantly decreased in tumor tissues compared with adjacent normal lung tissues (P < 0.001), and patients with lung cancer with higher levels of NME2 had longer survival outcomes (overall survival, P < 0.01; disease-free survival, P < 0.01). Mechanistically, CARMA3 promoted cell motility by reducing the level of NME2 through the NF-κB/miR-182 pathway and by increasing cancer stem cell properties and metastasis in lung cancer.

CONCLUSIONS

We identified a novel mechanism of CARMA3 in lung cancer stemness and metastasis through the negative regulation of NME2 by NF-κB-dependent induction of miR-182. Our findings provide an attractive strategy for targeting the CARMA3/NF-κB/miR-182 pathway as a potential treatment for lung cancer.

Prognostic Role of MicroRNA-126 for Survival in Malignant Tumors: A Systematic Review and Meta-Analysis

Background. Increasing studies found that miR-126 expression may be associated with the prognosis of cancers. Here, we performed a meta-analysis to assess the prognostic role of miR-126 in different cancers. Methods. Eligible studies were identified by searching in PubMed, Embase, the Cochrane Library, CNKI, and Wan Fang databases up to March 2015. Pooled hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) were calculated to investigate the correlation between miR-126 and survival of cancers. Results. Thirty studies including a total of 4497 participants were enrolled in this meta-analysis. The pooled results showed that high level of miR-126 was a predictor for favorable survival of carcinomas, with pooled HR of 0.77 (95% CI 0.64–0.93) for OS, 0.64 (95%CI 0.48–0.85) for DFS, and 0.70 (95% CI 0.50–0.98) for PFS/RFS/DSS. However, high level of circulating miR-126 predicted a significantly worse OS in patients with cancer (HR = 1.65, 95% CI 1.09–2.51). Conclusions. Our results indicated that miR-126 could act as a significant biomarker in the prognosis of various cancers.

miRNA detection methods and clinical implications in lung cancer

Lung cancer is the leading cause of cancer death worldwide. Therefore, advances in the diagnosis and treatment of the disease are urgently needed. miRNAs are a family of small, noncoding RNAs that regulate gene expression at the transcriptional level. miRNAs have been reported to be deregulated and to play a critical role in different types of cancer, including lung cancer. Thus, miRNA profiling in lung cancer patients has become the core of several investigations. To this end, the development of a multitude of platforms for miRNA profiling analysis has been essential. This article focuses on the different technologies available for assessing miRNAs and the most important results obtained to date in lung cancer.

Key nodes of a microRNA network associated with the integrated mesenchymal subtype of high-grade serous ovarian cancer

Metastasis is the main cause of cancer mortality. One of the initiating events of cancer metastasis of epithelial tumors is epithelial-to-mesenchymal transition (EMT), during which cells dedifferentiate from a relatively rigid cell structure/morphology to a flexible and changeable structure/morphology often associated with mesenchymal cells. The presence of EMT in human epithelial tumors is reflected by the increased expression of genes and levels of proteins that are preferentially present in mesenchymal cells. The combined presence of these genes forms the basis of mesenchymal gene signatures, which are the foundation for classifying a mesenchymal subtype of tumors. Indeed, tumor classification schemes that use clustering analysis of large genomic characterizations, like The Cancer Genome Atlas (TCGA), have defined mesenchymal subtype in a number of cancer types, such as high-grade serous ovarian cancer and glioblastoma. However, recent analyses have shown that gene expression-based classifications of mesenchymal subtypes often do not associate with poor survival. This “paradox” can be ameliorated using integrated analysis that combines multiple data types. We recently found that integrating mRNA and microRNA (miRNA) data revealed an integrated mesenchymal subtype that is consistently associated with poor survival in multiple cohorts of patients with serous ovarian cancer. This network consists of 8 major miRNAs and 214 mRNAs. Among the 8 miRNAs, 4 are known to be regulators of EMT. This review provides a summary of these 8 miRNAs, which were associated with the integrated mesenchymal subtype of serous ovarian cancer.

miR-139 and miR-200c regulate pancreatic cancer endothelial cell migration and angiogenesis

Pancreatic cancer remains the fourth deathliest cancer worldwide with a 5-year survival rate of only 4%. The present study tested the hypothesis that dysregulated microRNA (miRNA) expression by pancreatic cancer endothelial cells (CECs) may regulate angiogenesis. Primary EC cultures were established from the pancreatic tumor and adjacent normal tissues of three pancreatic cancer patients. A miRNA microarray was used to identify miRNAs that were differentially expressed. The expression patterns of four highly expressed miRNAs in CECs were confirmed by qPCR analysis. The effects of dysregulated miRNA expression on CEC proliferation, migration and tube formation were determined after transfection with specific miRNA inhibitors. The expression of 14 miRNAs was increased by >20-fold in the the CECs of all three pancreatic patients; the increased expression of miR-200c and miR-139 in CECs was confirmed. miR-1, mir-139 and miR-200c inhibitors significantly reduced CEC migration (all P<0.05), yet not proliferation. The average tube length and total loop number were also significantly decreased upon miR-139 and miR-200c inhibition in all three CEC cultures (all P<0.05). Upregulation of miR-139 and miR-200c expression may increase CEC migration and tube formation, which suggests that these miRNAs may regulate pancreatic tumor angiogenesis.

Tracking miRNAs' footprints in tumor-microenvironment interactions: Insights and implications for targeted cancer therapy

In the past decades, cancer medicine studies have mainly focused on tumor cell biology as the main promoter of solid tumor progression. However, tumor biology does not explain the intertwinement and ambiguity of the tumors' territory. Recently, the approach of understanding cancer has shifted from investigating the biology of tumor cells to studying the microenvironment surrounding them. MicroRNAs (miRNAs), which play a role in exploiting indigenous stromal cells and are components that cooperate and produce a favorable microenvironment for progressive tumor formation, have been implicated in numerous processes essential for tumor initiation and growth. Understanding the mechanisms underlying interactions between tumor cells and their adjacent environment holds many promises for the future of cancer-targeted therapies. Herein, we provide a step-by-step account of miRNA involvement in tumor-microenvironment interactions as the micromediators of tumor cell and stroma communications. We also focus on the clinical challenges in using miRNAs tof overcome therapy resistance mechanisms and tumor heterogeneity bias in cancer therapy.

Restoration of miR-424 suppresses BCR-ABL activity and sensitizes CML cells to imatinib treatment

MicroRNAs (miRNAs) are small noncoding RNAs that participate in many biological processes by posttranscriptionally regulating gene expression. Dysregulation of miRNA expression has been shown to be typical of many neoplasms. Chronic myeloid leukemia (CML) is a disorder of hematopoietic stem cells carrying the Philadelphia (Ph) chromosome and an oncogenic BCR-ABL tyrosine kinase fusion gene. While the development of tyrosine kinase inhibitors (TKIs) like imatinib has revolutionized treatment of CML, it has become increasingly clear in recent years that TKI treatment alone will not be curative in many cases. Thus, further dissection of the regulatory networks that drive BCR-ABL-induced malignant transformation may help to identify other novel therapeutic approaches that complement TKI treatment. In this study we demonstrate that the expression of miR-424 is markedly low in CML cell lines and patient samples at time of diagnosis. With the aid of bioinformatics analysis we revealed a conserved target site for miR-424 in the 3'-untranslated region (UTR) of the ABL gene. Via luciferase assays, we showed that miR-424 directly targets BCR-ABL. Overexpression of miR-424 was shown to suppress proliferation and induce apoptosis of K562 cells as well as sensitize these cells to imatinib treatment. These findings strongly suggest that miR-424 acts as a tumor suppressor by downregulating BCR-ABL expression. Up-regulation of miR-424 in CML cells may therefore have a therapeutic effect against this disease.

Prognostic value of the MicroRNA regulators Dicer and Drosha in non-small-cell lung cancer: co-expression of Drosha and miR-126 predicts poor survival

Background

Dicer and Drosha are important enzymes for processing microRNAs. Recent studies have exhibited possible links between expression of different miRNAs, levels of miRNA processing enzymes, and cancer prognosis. We have investigated the prognostic impact of Dicer and Drosha and their correlation with miR-126 expression in a large cohort of non-small cell lung cancer (NSCLC) patients. We aimed to find patient groups within the cohort that might have an advantage of receiving adjunctive therapies.

Methods

Dicer expression in the cytoplasm and Drosha expression in the nucleus were evaluated by manual immunohistochemistry of tissue microarrays (TMAs), including tumor tissue samples from 335 patients with resected stages I to IIIA NSCLC. In addition, in situ hybridizations of TMAs for visualization of miR-126 were performed. Kaplan–Meier analysis was performed, and the log-rank test via SPSS v.22 was used for estimating significance levels.

Results

In patients with normal performance status (ECOG = 0, n = 197), high Dicer expression entailed a significantly better prognosis than low Dicer expression (P = 0.024). Dicer had no significant prognostic value in patients with reduced performance status (ECOG = 1–2, n = 138). High Drosha expression was significantly correlated with high levels of the microRNA 126 (miR-126) (P = 0.004). Drosha/miR-126 co-expression had a significant negative impact on the disease-specific survival (DSS) rate (P < 0.001). Multivariate analyses revealed that the interaction Dicer*Histology (P = 0.049) and Drosha/miR-126 co-expression (P = 0.033) were independent prognostic factors.

Conclusions

In NSCLC patients with normal performance status, Dicer is a positive prognostic factor. The importance of Drosha as a prognostic factor in our material seems to be related to miR-126 and possibly other microRNAs.

Electronic supplementary material

The online version of this article (doi:10.1186/1472-6890-14-45) contains supplementary material, which is available to authorized users.

Vascular remodeling process in pulmonary arterial hypertension, with focus on miR-204 and miR-126 (2013 Grover Conference series)

Pulmonary arterial hypertension (PAH) is a vascular remodeling disease characterized primarily by increased proliferation and resistance to apoptosis in distal pulmonary arteries. Previous literature has demonstrated that the transcription factors NFAT (nuclear factor of activated T cells) and HIF-1α (hypoxia inducible factor 1α) are extensively involved in the pathogenesis of this disease and, more recently, has implicated STAT3 (signal transducer and activator of transcription 3) in their activation. Novel research shows that miR-204, a microRNA recently found to be notably downregulated through induction of PARP-1 (poly [ADP-ribose] polymerase 1) by excessive DNA damage in PAH, inhibits activation of STAT3. Contemporary research also indicates systemic impairment of skeletal muscle microcirculation in PAH and attributes this to a debilitated vascular endothelial growth factor pathway resulting from reduced miR-126 expression in endothelial cells. In this review, we focus on recent research implicating miR-204 and miR-126 in vascular remodeling processes, data that allow a better understanding of PAH molecular pathways and constitute a new hope for future therapy.

MicroRNA profiles discriminate among colon cancer metastasis

MicroRNAs are being exploited for diagnosis, prognosis and monitoring of cancer and other diseases. Their high tissue specificity and critical role in oncogenesis provide new biomarkers for the diagnosis and classification of cancer as well as predicting patients' outcomes. MicroRNAs signatures have been identified for many human tumors, including colorectal cancer (CRC). In most cases, metastatic disease is difficult to predict and to prevent with adequate therapies. The aim of our study was to identify a microRNA signature for metastatic CRC that could predict and differentiate metastatic target organ localization. Normal and cancer tissues of three different groups of CRC patients were analyzed. RNA microarray and TaqMan Array analysis were performed on 66 Italian patients with or without lymph nodes and/or liver recurrences. Data obtained with the two assays were analyzed separately and then intersected to identify a primary CRC metastatic signature. Five differentially expressed microRNAs (hsa-miR-21, -103, -93, -31 and -566) were validated by qRT-PCR on a second group of 16 American metastatic patients. In situ hybridization was performed on the 16 American patients as well as on three distinct commercial tissues microarray (TMA) containing normal adjacent colon, the primary adenocarcinoma, normal and metastatic lymph nodes and liver. Hsa-miRNA-21, -93, and -103 upregulation together with hsa-miR-566 downregulation defined the CRC metastatic signature, while in situ hybridization data identified a lymphonodal invasion profile. We provided the first microRNAs signature that could discriminate between colorectal recurrences to lymph nodes and liver and between colorectal liver metastasis and primary hepatic tumor.

Multiple functions of hypoxia-regulated miR-210 in cancer

MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression post-transcriptionally. miRNAs can be induced by a variety of stresses such as hypoxia, and are involved in diverse biological processes including differentiation, cell proliferation, cell death, and tumorigenesis. Hypoxia, a common feature of tumor microenvironment, can induce a number of miRNAs expression. miRNA-210 (miR-210) is one of the hypoxia-regulated-miRNAs, which has been investigated extensively in cancer. However, paradoxically opposing results were documented regarding whether it is an oncogene or a tumor suppressor, and whether it is a positive or negative prognostic biomarker. In the present review, we focus on the following investigations of miR-210: 1) its functions of as an oncogene, 2) its functions as a tumor suppressor, 3) its functions in mitochondrial metabolism, and finally, the diagnostic and prognostic value of miR-210 in cancer researches.