Potential diagnostic value of miR-155 in serum from lung adenocarcinoma patients

The diagnostic performance of micro-RNA and metabolites in lung cancer: A meta-analysis

BACKGROUND

The diagnosis of lung cancer is based on the microscopic exam of tissue or liquid. During the recent decade, many biomarkers have been pointed to have a potential diagnostic role. These biomarkers may be assessed in blood, pleural effusion or sputum and they could avoid biopsies or other risky procedures. The authors aimed to assess the diagnostic performances of biomarkers focusing on micro-RNA and metabolites.

METHODS

This meta-analysis was conducted under the PRISMA guidelines during a nine-year-period (2013-2022). the Meta-Disc software 5.4 (free version) was used. Q test and I2 statistics were carried out to explore the heterogeneity among studies. Meta-regression was performed in case of significant heterogeneity. Publication bias was assessed using the funnel plot test and the Egger's test (free version JASP).

RESULTS

According to our inclusion criteria, 165 studies from 79 articles were included. The pooled SEN, SPE and dOR accounted, respectively, for 0.76, 0.79 and 13.927. The AUC was estimated to 0.859 suggesting a good diagnostic accuracy. The heterogeneity in the pooled SEN and SPE was statistically significant. The meta-regression analysis focusing on the technique used, the sample, the number of biomarkers, the biomarker subtype, the tumor stage and the ethnicity revealed the biomarker number (p  =  0.009) and the tumor stage (p  =  0.0241) as potential sources of heterogeneity.

CONCLUSION

Even if this meta-analysis highlighted the potential diagnostic utility of biomarkers, more prospective studies should be performed, especially to assess the biomarkers' diagnostic potential in early-stage lung cancers.

Recent advances on high-efficiency of microRNAs in different types of lung cancer: a comprehensive review

Carcinoma of the lung is among the most common types of cancer globally. Concerning its histology, it is categorized as a non-small cell carcinoma (NSCLC) and a small cell cancer (SCLC) subtype. MicroRNAs (miRNAs) are a member of non-coding RNA whose nucleotides range from 19 to 25. They are known to be critical regulators of cancer via epigenetic control of oncogenes expression and by regulating tumor suppressor genes. miRNAs have an essential function in a tumorous microenvironment via modulating cancer cell growth, metastasis, angiogenesis, metabolism, and apoptosis. Moreover, a wide range of information produced via several investigations indicates their tumor-suppressing, oncogenic, diagnostic assessment, and predictive marker functions in different types of lung malignancy. miRNA mimics or anti-miRNAs can be transferred into a lung cancer cell, with possible curative implications. As a result, miRNAs hold promise as targets for lung cancer treatment and detection. In this study, we investigate the different functions of various miRNAs in different types of lung malignancy, which have been achieved in recent years that show the lung cancer-associated regulation of miRNAs expression, concerning their function in lung cancer beginning, development, and resistance to chemotherapy, also the probability to utilize miRNAs as predictive biomarkers for therapy reaction.

MiRNAs in Lung Adenocarcinoma: Role, Diagnosis, Prognosis, and Therapy

Lung cancer has emerged as a significant public health challenge and remains the leading cause of cancer-related mortality worldwide. Among various types of lung malignancies, lung adenocarcinoma (LUAD) stands as the most prevalent form. MicroRNAs (miRNAs) play a crucial role in gene regulation, and their involvement in cancer has been extensively explored. While several reviews have been published on miRNAs and lung cancer, there remains a gap in the review regarding miRNAs specifically in LUAD. In this review, we not only highlight the potential diagnostic, prognostic, and therapeutic implications of miRNAs in LUAD, but also present an inclusive overview of the extensive research conducted on miRNAs in this particular context.

The Diagnostic and Prognostic Value of miR-155 in Cancers: An Updated Meta-analysis

BACKGROUND

MicroRNA-155 has been discussed as a biomarker in cancer diagnosis and prognosis. Although relevant studies have been published, the role of microRNA-155 remains uncertain because of insufficient data.

METHODS

We conducted a literature search in PubMed, Embase, and Web of Science databases to obtain relevant articles and extract data to evaluate the role of microRNA-155 in cancer diagnosis and prognosis.

RESULTS

The pooled results showed that microRNA-155 presented a remarkable diagnostic value in cancers (area under the curve = 0.90, 95% confidence interval (CI 0.87-0.92; sensitivity = 0.83, 95% CI 0.79-0.87; specificity = 0.83, 95% CI 0.80-0.86), which was maintained in the subgroups stratified by ethnicity (Asian and Caucasian), cancer types (breast cancer, lung cancer, hepatocellular carcinoma, leukemia, and pancreatic ductal adenocarcinoma), sample types (plasma, serum, tissue), and sample size (n >100 and n <100). In prognosis, a combined hazard ratio (HR) showed that microRNA-155 was significantly associated with poor overall survival (HR = 1.38, 95% CI 1.25-1.54) and recurrence-free survival (HR = 2.13, 95% CI 1.65-2.76), and was boundary significant with poor progression-free survival (HR = 1.20, 95% CI 1.00-1.44), but not significant with disease-free survival (HR = 1.14, 95% CI 0.70-1.85). Subgroup analyses in overall survival showed that microRNA-155 was associated with poor overall survival in the subgroups stratified by ethnicity and sample size. However, the significant association was maintained in cancer types subgroups of leukemia, lung cancer, and oral squamous cell carcinoma, but not in colorectal cancer, hepatocellular carcinoma, and breast cancer, and was maintained in sample types subgroups of bone marrow and tissue, but not in plasma and serum.

CONCLUSIONS

Results from this meta-analysis demonstrated that microRNA-155 was a valuable biomarker in cancer diagnosis and prognosis.

Contributions of Circulating microRNAs for Early Detection of Lung Cancer

There is unmet need to develop circulating biomarkers that would enable earlier interception of lung cancer when more effective treatment options are available. Here, a set of 30 miRNAs, selected from a review of the published literature were assessed for their predictive performance in identifying lung cancer cases in the pre-diagnostic setting. The 30 miRNAs were assayed using sera collected from 102 individuals diagnosed with lung cancer within one year following blood draw and 212 controls matched for age, sex, and smoking status. The additive performance of top-performing miRNA candidates in combination with a previously validated four-protein marker panel (4MP) consisting of the precursor form of surfactant protein B (Pro-SFTPB), cancer antigen 125 (CA125), carcinoembryonic antigen (CEA) and cytokeratin-19 fragment (CYFRA21-1) was additionally assessed. Of the 30 miRNAs evaluated, five (miR-320a-3p, miR-210-3p, miR-92a-3p, miR-21-5p, and miR-140-3p) were statistically significantly (Wilcoxon rank sum test p < 0.05) elevated in case sera compared to controls, with individual AUCs ranging from 0.57−0.62. Compared to the 4MP alone, the combination of 3-miRNAs + 4MP improved sensitivity at 95% specificity by 19.1% ((95% CI of difference 0.0−28.6); two-sided p: 0.006). Our findings demonstrate utility for miRNAs for early detection of lung cancer in combination with a four-protein marker panel.

Bipartite graph-based collaborative matrix factorization method for predicting miRNA-disease associations

BACKGROUND

With the rapid development of various advanced biotechnologies, researchers in related fields have realized that microRNAs (miRNAs) play critical roles in many serious human diseases. However, experimental identification of new miRNA-disease associations (MDAs) is expensive and time-consuming. Practitioners have shown growing interest in methods for predicting potential MDAs. In recent years, an increasing number of computational methods for predicting novel MDAs have been developed, making a huge contribution to the research of human diseases and saving considerable time. In this paper, we proposed an efficient computational method, named bipartite graph-based collaborative matrix factorization (BGCMF), which is highly advantageous for predicting novel MDAs.

RESULTS

By combining two improved recommendation methods, a new model for predicting MDAs is generated. Based on the idea that some new miRNAs and diseases do not have any associations, we adopt the bipartite graph based on the collaborative matrix factorization method to complete the prediction. The BGCMF achieves a desirable result, with AUC of up to 0.9514 ± (0.0007) in the five-fold cross-validation experiments.

CONCLUSIONS

Five-fold cross-validation is used to evaluate the capabilities of our method. Simulation experiments are implemented to predict new MDAs. More importantly, the AUC value of our method is higher than those of some state-of-the-art methods. Finally, many associations between new miRNAs and new diseases are successfully predicted by performing simulation experiments, indicating that BGCMF is a useful method to predict more potential miRNAs with roles in various diseases.

Downregulated Expression of CLEC9A as Novel Biomarkers for Lung Adenocarcinoma

Purpose

Abnormal CLEC9A expression is concerned with carcinogenesis. However, the role of CLEC9A in lung adenocarcinoma (LUAD) remains unknown. The goal of this study was to reveal the role of CLEC9A in LUAD based on bioinformatics and cellular functional experiments.

Materials and methods

Data available from The Cancer Genome Atlas (TCGA) were employed to study CLEC9A expression and mutations in LUAD. Expression and alterations of CLEC9A were analyzed using UALCAN and cBioPortal, respectively. Kaplan-Meier analysis was used to analyze the effect of CLEC9A on the survival of LUAD. Protein-protein interaction (PPI) network was built using GeneMANIA analysis. The similar genes of CLEC9A were obtained using GEPIA analysis, while co-expression genes correlated with CLEC9A were identified using LinkedOmics analysis. The effects of CLEC9A expression on immune cell infiltration was assessed. The effect of CLEC9A on the proliferation, apoptosis, cell cycle distribution, and invasion of human LUAD cells was detected in the LUAD cell line.

Results

CLEC9A was downregulated and the CLEC9A gene was often altered in LUAD. The survival of LUAD patients was correlated with the expression level of CLEC9A. The similar genes of CLEC9A were linked to functional networks involving positive regulation of interleukin-12 production, plasma membrane and CD40 receptor binding, primary immunodeficiency, intestinal immune network for IgA production, and cell adhesion molecules pathways. Cell cycle, apoptosis, EMT, and RAS/MAPK were significantly enriched pathways in positive and negative correlation genes with CLEC9A. A difference in the immune infiltration level of immune cell between the high and low CLEC9A expression groups was observed. Somatic cell copy number alternations (CNAs) of the CLEC9A, including arm-level gain and arm-level deletion, observably changed the infiltration levels of B cells, CD4+ T cells, macrophages, and neutrophils in LUAD. Except for LAG3, the expression of CD274, CTLA4, PDCD1, and TIGIT was positively correlated with the expression level of CLEC9A. After transfection, overexpression and knockdown of CLEC9A could affect the proliferation, apoptosis, cell cycle distribution, and invasion of LUAD cells.

Conclusion

CLEC9A is associated with prognosis and tumor immune microenvironment of LUAD, suggesting that CLEC9A may be considered as a novel biomarker for LUAD.

Multicolor fluorescence encoding of different microRNAs in lung cancer tissues at the single-molecule level

The simultaneous detection of multiple microRNAs (miRNAs) will facilitate early clinical diagnosis. Herein, we demonstrate the integration of multicolor fluorophore-encoded cascade signal amplification with single-molecule detection for simultaneous measurement of different miRNAs in lung cancer tissues. This assay involves two linear templates and two circular templates without the requirement of any fluorescent-labeled probes. The binding of target miRNAs to their corresponding linear templates initiates the cyclic strand displacement amplification, generating many triggers which can specifically hybridize with the corresponding biotin-labeled AP probes to initiate the apurinic/apyrimidic endonuclease 1-assisted cyclic cleavage reaction for the production of more biotin-labeled primers for each miRNA. The resultant two primers can react with their corresponding circular templates to initiate rolling circle amplification which enables the incorporation of Cy5-dCTP/Cy3-dGTP nucleotides, resulting in the simultaneous production of abundant biotin-/multiple Cy5/Cy3-labeled DNA products. After magnetic separation and exonuclease cleavage, the amplified products release abundant Cy5 and Cy3 fluorescent molecules which can be simply monitored by single-molecule detection, with Cy3 indicating miR-21 and Cy5 indicating miR-155. This assay involves three consecutive amplification reactions, enabling the conversion of extremely low abundant target miRNAs into large numbers of Cy5/Cy3 fluorophore-encoded DNA products which can release abundant fluorescent molecules for the generation of amplified signals. This assay exhibits high sensitivity, good selectivity, and the capability of multiplexed assay. This method can simultaneously quantify miR-155 and miR-21 in living cells and in lung cancer tissues, and it can distinguish the expression of miRNAs between non-small cell lung cancer patients and healthy persons. The accuracy and reliability of the proposed method are further validated by quantitative reverse transcription polymerase chain reaction.

High Diagnostic and Prognostic Value of miRNAs Compared with the Carcinoembryonic Antigen as a Traditional Tumor Marker

A significant challenge in cancer detection and treatment is early diagnosis and accurate prognosis of the disease that enables effective therapies and interventions to improve the patient's condition. Up to now, many parts of research have tended to focus on the carcinoembryonic antigen (CEA) to detect cancers and estimate the survival rates of patients with multiple cancer types, including colorectal, breast, non-small cell lung, and pancreas cancer. Limited sensitivity and specificity of this traditional tumor marker make it an inappropriate biomarker to diagnose cancer, especially in the early stages, while several lines of research have introduced miRNAs as reliable indicators of tumor initiation, development, and therapy response. Indeed, miRNAs have unique properties that provide considerable benefits, such as discriminating benign diseases from malignancies, prediction of cancer possibility and progress, checking sensitivity to treatment, and initial detection of tumors. This review summarizes the relationships between miRNAs and CEA, the diagnostic significance of CEA in combination with miRNAs, and the distinct advantages of miRNAs over CEA as tumor biomarkers. Advancement in our current understanding of miRNAs is essential to discover new and effective biomarkers for diagnostic, prognostic, and therapeutic goals of cancer patients.

miRNAs in lung cancer. A systematic review identifies predictive and prognostic miRNA candidates for precision medicine in lung cancer

Lung cancer (LC) is the leading cause of cancer-related death worldwide and miRNAs play a key role in LC development. To better diagnose LC and to predict drug treatment responses we evaluated 228 articles encompassing 16,697 patients and 12,582 healthy controls. Based on the criteria of ≥3 independent studies and a sensitivity and specificity of >0.8 we found blood-borne miR-20a, miR-10b, miR-150, and miR-223 to be excellent diagnostic biomarkers for non-small cell LC whereas miR-205 is specific for squamous cell carcinoma. The systematic review also revealed 38 commonly regulated miRNAs in tumor tissue and the circulation, thus enabling the prediction of histological subtypes of LC. Moreover, theranostic biomarker candidates with proven responsiveness to checkpoint inhibitor treatments were identified, notably miR-34a, miR-93, miR-106b, miR-181a, miR-193a-3p, and miR-375. Conversely, miR-103a-3p, miR-152, miR-152-3p, miR-15b, miR-16, miR-194, miR-34b, and miR-506 influence programmed cell death-ligand 1 and programmed cell death-1 receptor expression, therefore providing a rationale for the development of molecularly targeted therapies. Furthermore, miR-21, miR-25, miR-27b, miR-19b, miR-125b, miR-146a, and miR-210 predicted response to platinum-based treatments. We also highlight controversial reports on specific miRNAs. In conclusion, we report diagnostic miRNA biomarkers for in-depth clinical evaluation. Furthermore, in an effort to avoid unnecessary toxicity we propose predictive biomarkers. The biomarker candidates support personalized treatment decisions of LC patients and await their confirmation in randomized clinical trials.

Rola miRNA w rozwoju wybranych nowotworów – potencjalne zastosowanie w diagnostyce*

MikroRNA (miRNA) są małymi cząsteczkami kwasu rybonukleinowego, które mimo że nie podlegają procesowi translacji, pełnią ważną funkcję regulacyjną w komórkach eukariotycznych. Ich fizjologiczną funkcją jest utrzymywanie homeostazy komórek. Zaburzona ekspresja miRNA może spowodować rozwój wielu chorób, w tym chorób nowotworowych. Działanie miRNA polega na hamowaniu tworzenia się białek, w tym białek o właściwościach onkogennych i antyonkogennych. Mutacje w miejscach kodowania miRNA mogą prowadzić do nadmiernego lub zmniejszonego wytwarzania wspomnianych białek. Odkrycie miRNA i poznanie ich roli w komórce otworzyło nowe możliwości dla diagnostyki chorób nowotworowych. Zmiany poziomu odpowiednich miRNA, w krwiobiegu lub innych płynach ustrojowych, mogą być markerem diagnostycznym chorób. Diagnostyka onkologiczna mogłaby przebiegać na podstawie badań profilu miRNA pacjenta i porównania go z opracowanymi wcześniej profilami zmian miRNA powiązanymi z występowaniem danego rodzaju choroby nowotworowej. Informacja o zmianach profilu miRNA podstawowych w regulacji ekspresji genów związanych z procesami nowotworzenia, mogłaby się przyczynić do opracowania terapii eksperymentalnych opartych na przywróceniu pierwotnego poziomu miRNA w komórkach, a tym samym, na przywróceniu prawidłowej regulacji ekspresji genów. Coraz nowsze metody wyciszania i włączania ekspresji miRNA mogą w przyszłości zaowocować skutecznymi rozwiązaniami terapeutycznymi.

Plasma endothelial microvesicles and their carrying miRNA-155 serve as biomarkers for ischemic stroke

Endothelial microvesicles (EMVs) could reflect the status of endothelial cells (ECs) which are involved in the pathogenesis of ischemic stroke (IS). MiR-155 could regulate EC functions. However, their roles in IS remain unclear. This study aimed to investigate the levels of plasma EMVs and EMVs carrying miRNA-155 (EMVs-miR-155) in IS patients to explore their potential roles as biomarkers. Ninety-three IS patients and 70 controls were recruited in this study. The levels of circulating EMVs and EMVs-miR-155 were detected by fluorescence nanoparticle tracking analysis and quantitative real-time PCR, respectively. The correlations between level of EMVs/EMVs-miR-155 and the onset time, severity, infarct volume, and subtypes of IS were analyzed. The severity and infarct volume were assessed by NIHSS and magnetic resonance imaging, respectively. Multivariate logistic regression analysis was used to investigate the risk factors of IS. The ROC curve and area under ROC curve (AUC) of EMVs and EMVs-miR-155 were determined. The levels of plasma EMVs and EMVs-miR-155 were increased significantly in acute and subacute stages of IS and remained unchanged in chronic stage, and were positively related to the infarct volume and NIHSS scores and were associated with large artery atherosclerosis and cardioembolism subtypes defined by Trial of Org 10 172 in acute stroke treatment (TOAST) classification. Multivariate logistic regression analysis demonstrated that plasma EMVs and EMVs-miR-155 were significant and independent risk factors of IS and their AUC were 0.778 and 0.851, respectively, and increased to 0.892 after combination. Our study suggests that plasma EMVs and EMVs-miR-155 are promising biomarkers for IS. The diagnostic value of EMVs-miR-155 is higher and their combination is the best.

Circulating MicroRNAs Regulating DNA Damage Response and Responsiveness to Cisplatin in the Prognosis of Patients with Non-Small Cell Lung Cancer Treated with First-Line Platinum Chemotherapy

The expression of microRNA (miR)-21, miR-128, miR-155, and miR-181a involved in DNA damage response (DDR) and tumor responsiveness to platinum was assessed by RT-qPCR in the plasma of patients with non-small cell lung cancer (NSCLC; n = 128) obtained prior to initiation of first-line platinum chemotherapy. U6 small nuclear RNA (snRNA) was used for normalization, and fold change of each miRNA expression relative to the expression in healthy controls was calculated by the 2^−ΔΔCt method. MicroRNA expression levels were correlated with patients’ outcomes. Integrated function and pathway enrichment analysis was performed to identify putative target genes. MiR-128, miR-155, and miR-181a expressions were higher in patients compared to healthy donors. MiRNA expression was not associated with response to treatment. High miR-128 and miR-155 were correlated with shorter overall survival (OS), whereas performance status (PS) 2 and high miR-128 independently predicted for decreased OS. In the squamous (SqCC) subgroup (n = 41), besides miR-128 and miR-155, high miR-21 and miR-181a expressions were also associated with worse survival and high miR-155 independently predicted for shorter OS. No associations of miRNA expression with clinical outcomes were observed in patients with non-SqCC (n = 87). Integrated function and pathway analysis on miRNA targets revealed significant enrichments in hypoxia-related pathways. Our study shows for the first time that plasma miR-128 and miR-155 hold independent prognostic implications in NSCLC patients treated with platinum-based chemotherapy possibly related to their involvement in tumor response to hypoxia. Further studies are needed to investigate the potential functional role of these miRNAs in an effort to exploit their therapeutic potential.

Combined eight-long noncoding RNA signature: a new risk score predicting prognosis in elderly non-small cell lung cancer patients

The elderly are the majority of patients with non-small cell lung cancer (NSCLC). Compared to the overall population's predictive guidance, an effective predictive guidance for elderly patients can better guide patients' postoperative treatment and improve overall survival (OS) and disease-free survival (DFS). Recently, the long non-coding RNAs (lncRNAs) have been found to play an important role in predicting tumor prognosis. To identify potential lncRNAs to predict survival in elderly patients with NSCLC, in the present study, we chose 456 elderly patients with NSCLC and analyzed differentially expressed lncRNAs from four Gene Expression Omnibus (GEO) datasets (GSE30219, GSE31546, GSE37745 and GSE50081). We then constructed an eight-lncRNA formula to predict elderly patients’ prognosis in NSCLC. Furthermore, we validated the prognostic values of the new risk model in two independent datasets, TCGA (n=670) and GSE31210 (n=130). Our data suggested a significant association between risk model and patients’ prognosis. Finally, stratification analysis further revealed the eight-lncRNA signature was an independent factor to predict OS and DFS in stage I elderly patients from both the discovery and validation groups. Functional prediction revealed that 8 lncRNAs have potential effects on tumor immune processes such as lymphocyte activation and TNF production in NSCLC. In summary, our data provides evidence that the eight-lncRNA signature could serve as an independent biomarker to predict prognosis in elderly patients with NSCLC especially in elderly stage I patients.

The value of miR-155 as a biomarker for the diagnosis and prognosis of lung cancer: a systematic review with meta-analysis

BACKGROUND

Recently, a growing number of studies have reported the coorelation between miR-155 and the diagnosis and prognosis of lung cancer, but results of these researches were still controversial due to insufficient sample size. Thus, we carried out the systematic review and meta-analysis to figure out whether miR-155 could be a screening tool in the detection and prognosis of lung cancer.

METHODS

A meta-analysis of 13 articles with 19 studies was performed by retrieving the PubMed, Embase and Web of Science. We screened all correlated literaters until December 1st, 2018. For the diagnosis analysis of miR-155 in lung cancer, sensitivity (SEN), specificity (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and area under the ROC curve (AUC) were pooled to evaluate the accuracy of miRNA-155 in the diagnosis of lung cancer. For the prognosis analysis of miR-155 in lung cancer, the pooled HRs and 95% CIs of miR-155 for overall survival/disease free survival/progression-free survival (OS/DFS/PFS) were calculated. In addition, Subgroup and meta-regression analyses were performed to distinguish the potential sources of heterogeneity between studies.

RESULTS

For the diagnostic analysis of miR-155 in lung cancer, the pooled SEN and SPE were 0.82 (95% CI: 0.72-0.88) and 0.78 (95% CI: 0.71-0.84), respectively. Besides, the pooled PLR was 3.75 (95% CI: 2.76-5.10), NLR was 0.23 (95% CI: 0.15-0.37), DOR was 15.99 (95% CI: 8.11-31.52) and AUC was 0.87 (95% CI: 0.84-0.90), indicating a significant value of miR-155 in the lung cancer detection. For the prognostic analysis of miR-155 in lung cancer, up-regulated miRNA-155 expression was not significantly associated with a poor OS (pooled HR = 1.26, 95% CI: 0.66-2.40) or DFS/PFS (pooled HR = 1.28, 95% CI: 0.82-1.97).

CONCLUSIONS

The present meta-analysis demonstrated that miR-155 could be a potential biomarker for the detection of lung cancer but not an effective biomarker for predicting the outcomes of lung cancer. Furthermore, more well-designed researches with larger cohorts were warranted to confirm the value of miR-155 for the diagnosis and prognosis of lung cancer.

Circulating miRNAs as Diagnostic and Prognostic Biomarkers in Common Solid Tumors: Focus on Lung, Breast, Prostate Cancers, and Osteosarcoma

An early cancer diagnosis is essential to treat and manage patients, but it is difficult to achieve this goal due to the still too low specificity and sensitivity of classical methods (imaging, actual biomarkers), together with the high invasiveness of tissue biopsies. The discovery of novel, reliable, and easily collectable cancer markers is a topic of interest, with human biofluids, especially blood, as important sources of minimal invasive biomarkers such as circulating microRNAs (miRNAs), the most promising. MiRNAs are small non-coding RNAs and known epigenetic modulators of gene expression, with specific roles in cancer development/progression, which are next to be implemented in the clinical routine as biomarkers for early diagnosis and the efficient monitoring of tumor progression and treatment response. Unfortunately, several issues regarding their validation process are still to be resolved. In this review, updated findings specifically focused on the clinical relevance of circulating miRNAs as prognostic and diagnostic biomarkers for the most prevalent cancer types (breast, lung, and prostate cancers in adults, and osteosarcoma in children) are described. In addition, deep analysis of pre-analytical, analytical, and post-analytical issues still affecting the circulation of miRNAs' validation process and routine implementation is included.

Electrochemical-based biosensors for microRNA detection: Nanotechnology comes into view

Nanotechnology plays an undeniable significant role in medical sciences, particularly in the field of biomedicine. Development of several diagnostic procedures in medicine has been possible through the beneficial application of nano-materials, among which electrochemical nano-biosensors can be mentioned. They can be employed to quantify various clinical biomarkers in detection, evaluation, and follow up stages of the illnesses. MicroRNAs, a group of regulatory short RNA fragments, added a new dimension to the management and diagnosis of several diseases. Mature miRNAs are single-stranded RNA molecules approximately 22 nucleotides in length, which regulate a vast range of biological functions from cellular proliferation and death to cancer development and progression. Recently, diagnostic value of miRNAs in various diseases has been demonstrated. There are many traditional methods for detection of miRNAs including northern blotting, quantitative real time PCR (qRT-PCR), microarray technology, nanotechnology-based approaches, and molecular biology tools including miRNA biosensors. In comparison with other techniques, electrochemical nucleic acid biosensor methods exhibit many interesting features, and could play an important role in the future nucleic acid analysis. This review paper provides an overview of some different types of nanotechnology-based biosensors for detection of miRNAs.

Circulating MicroRNA Biomarkers for Lung Cancer Detection in East Asian Populations

BACKGROUND

Lung cancer (LC) is the leading cause of cancer-related death in Eastern Asia. The prognosis of LC highly depends on tumor stages and early detection could substantially reduce LC mortality. Accumulating evidence suggested that circulating miRNAs in plasma or serum may have applications in early LC detection. We thus conducted a systematic literature review on the diagnostic value of miRNAs markers for LC in East Asian populations.

METHODS

PubMed and ISI Web of Knowledge were searched to retrieve relevant articles published up to 17 September 2018. Information on study design, population characteristics, investigated miRNAs and diagnostic accuracy (including sensitivity, specificity and area under the curve (AUC)) were independently extracted by two reviewers.

RESULTS

Overall, 46 studies that evaluated a total of 88 miRNA markers for LC diagnosis in East Asian populations were identified. Sixteen of the 46 studies have incorporated individual miRNA markers as panels (with 2⁻20 markers). Three promising miRNA panels with ≥90% sensitivity and ≥90% specificity were discovered, two of which were externally validated. Diagnostic performance of circulating miRNAs in East Asian populations was comparable to previously summarized performance in Western populations. Forty-four miRNAs were reported in both populations. No major differences in diagnostic performance by ethnicity of the same miRNA was observed.

CONCLUSIONS

Circulating miRNAs or miRNA panels, possibly in combination with other promising molecular markers including epigenetic and genetic markers, may be promising candidates for noninvasive LC early detection. However, large studies with samples collected prospectively in true screening settings are required to validate the promising markers or marker panels.

MicroRNA in lung cancer: role, mechanisms, pathways and therapeutic relevance

Lung cancer is the cardinal cause of cancer-related deaths with restricted recourse of therapy throughout the world. Clinical success of therapies is not very promising due to - late diagnosis, limited therapeutic tools, relapse and the development of drug resistance. Recently, small ∼20-24 nucleotides molecules called microRNAs (miRNAs) have come into the limelight as they play outstanding role in the process of tumorigenesis by regulating cell cycle, metastasis, angiogenesis, metabolism and apoptosis. miRNAs essentially regulate gene expression via post-transcriptional regulation of mRNA. Nevertheless, few studies have conceded the role of miRNAs in activation of gene expression. A large body of data generated by numerous studies is suggestive of their tumor-suppressing, oncogenic, diagnostic and prognostic biomarker roles in lung cancer. They have also been implicated in regulating cancer cell metabolism and resistance or sensitivity towards chemotherapy and radiotherapy. Further, miRNAs have also been convoluted in regulation of immune checkpoints - Programmed death 1 (PD-1) and its ligand (PD-L1). These molecules play a significant role in tumor immune escape leading to the generation of a microenvironment favouring tumor growth and progression. Therefore, it is imperative to explore the expression of miRNA and understand its relevance in lung cancer and development of anti-cancer strategies (anti - miRs, miR mimics and micro RNA sponges). In view of the above, the role of miRNA in lung cancer has been dissected and the associated mechanisms and pathways are discussed in this review.

Role of long non-coding RNA in drug resistance in non-small cell lung cancer

Lung cancer is the leading cause of cancer-associated death, and non-small cell lung cancer (NSCLC) accounts for 85% of all lung cancer cases. Many drugs have been used to treat NSCLC in order to improve patient prognosis. Platinum-based chemotherapy is the first-line treatment for locally advanced or metastatic patients. For patients with activating EGFR mutations, tyrosine kinase inhibitors are the best treatment choice. NSCLC initially exhibits an excellent response to treatment; however, acquired resistance has been observed in many patients, leading to ineffective treatment. Clinical resistance is an impediment in the treatment of patients with advanced NSCLC. Many sequencing technologies have shown that long non-coding RNA (lncRNA) is expressed differently between drug-resistant and drug-sensitive lung cancer cells. We review the literature on lncRNA in drug resistance of NSCLC. The aim of this review is to gain insight into the molecular mechanisms of drug resistance, mainly focusing on the role of lncRNA in NSCLC.

The SNAIL/miR-128 axis regulated growth, invasion, metastasis, and epithelial-to-mesenchymal transition of gastric cancer

miR-128 is expressed in various tumors, but its expression and function in gastric cancer have not been defined. Thus, the goal of this study was to characterize miR-128 in gastric cancer. We found first that miR-128 is down-regulated in gastric cancer cell lines and tissues, and this dysregulation is correlated with DNA methylation and the transcription factor SNAIL. Using prediction tools, western blotting, and luciferase reporter assays, we found that Bmi-1 was the direct target of miR-128. Additionally, overexpression of miR-128 inhibited gastric cancer cell migration, invasion, and proliferation by targeting Bmi-1 in vitro and in vivo. We also documented, with receiver operating characteristic curves and Kaplan-Meier survival analysis, that miR-128 and Bmi-1 may be useful markers for diagnosing and estimating the prognosis of gastric cancer patients. As the epithelial-to-mesenchymal transition is an important mechanism associated with cancer invasion and metastasis, we inferred that miR-128 could regulate this mechanism in gastric cancer. In fact, we found that miR-128 could reverse epithelial-to-mesenchymal transition induced by Bmi-1 via the PI3K/AKT pathway. Because SNAIL also acts as a mesenchymal marker, our findings identified a novel positive feedback loop in which the transcription factor SNAIL curbs the expression of miR-128, and then down-regulated miR-128 promotes the expression of Bmi-1; finally, overexpression of Bmi-1 drives the epithelial-to-mesenchymal transition process via the PI3K/AKT pathway, and the expression of SNAIL is up-regulated.

Circulating microRNA-339-5p and -21 in plasma as an early detection predictors of lung adenocarcinoma

BACKGROUND

Many studies have shown that differentially expressed miRs in body fluids can serve as biomarkers in non-invasive detection of the cancers. However, the clinical significance of plasma miRs in the diagnosis of lung adenocarcinoma (LA) is still not clear. Therefore, we examined the LA-specific miRs in plasma, which could be utilized to diagnosis and monitor LA in routine clinical practice.

METHODS

Twenty-eight LA cases and twenty-eight healthy controls were recruited to our study. MiRs differential expression in plasma was measured by miRNA Microarray assay and revalidated by using qRT-PCR based absolute quantification methods The diagnostic power of circulating miRs in LA was evaluated using the receiver operating characteristics (ROC) curves and the area under the ROC curves (AUC).

RESULTS

Tumor tissues and plasma levels of miR-339-5p were significantly down-regulated in LA patients compared with those in the control group, whereas the levels of miR-21 in LA patients were significantly higher than control group. ROC analysis showed that miR-339-5p and miR-21 could distinguish LA patients from healthy controls with high AUC (0.900 and 0.880, respectively), sensitivity (0.821 and 0.821, respectively) and specificity (0.929 and 0.964, respectively). Importantly, the combination of miR-339-5p and miR-21 markedly improved AUC (0.963), sensitivity (0.929) and specificity (0.929).

CONCLUSION

Plasma miR-339-5p or miR-21 could serve as a potential biomarker for diagnosis of LA, however, the combination of miR-339-5p and miR-21 was more efficient for LA detection.

A novel information diffusion method based on network consistency for identifying disease related microRNAs

The abnormal expression of miRNAs is directly related to the development of human diseases. Predicting the potential candidate miRNAs associated with diseases can contribute to the detection, diagnosis, treatment and prevention of human complex diseases. The effective inference of the calculation method of the relationship between miRNAs and diseases is an effective supplement to biological experiments. It is of great help in the prevention, treatment and prognosis of complex diseases. This paper proposes a novel information diffusion method based on network consistency (IDNC) for identifying disease related microRNAs. The model first synthesizes the miRNA family information and the miRNA function similarity to reconstruct the miRNA network, and reconstruct the disease network by using the known disease and miRNA-related information and the semantic score between diseases. Then the global similarity of the two networks is obtained by using the Laplacian score of graphs. The global similarity score is a measure of the similarity between diseases and miRNAs. The disease–miRNA relation network was reconstructed by integrating the global similarity relation. The network consistency diffusion seed is then obtained by combining the global similarity network with the reconstructed disease–miRNA association network. Thereafter, the stable diffusion spectrum is generated as the prediction score by using the restarted random walk algorithm. The AUC value obtained by performing the LOOCV in the gold benchmark dataset is 0.8814. The AUC value obtained by performing the LOOCV in the predictive dataset is 0.9512. Compared with other frontier methods, our method has higher accuracy, which is further illustrated by case studies of breast neoplasms and colon neoplasms to prove that IDNC is valuable.

The abnormal expression of miRNAs is directly related to the development of human diseases.

Identification of lung adenocarcinoma specific dysregulated genes with diagnostic and prognostic value across 27 TCGA cancer types

As the most common histologic subtype of lung cancer, lung adenocarcinoma (LUAD) contributes to a majority of cancer-related deaths worldwide annually. In order to find specific biomarkers of LUAD that are able to distinguish LUAD from other types of cancer so as to improve the early diagnostic and prognostic power in LUAD, we analyzed 10098 tumor tissue samples across 27 TCGA cancer types and identified 112 specific expressed genes in LUAD. Meantime, 8240 LUAD dysregulated genes in tumor and normal samples were identified. Combining with the results of specific expressed genes and dysregulated genes in LUAD, we found there were 70 specific dysregulated genes in LUAD (LUAD-SDGs). Then ROC curve revealed six LUAD-SDGs that may be of strong diagnostic value to predict the existence of cancer (area under curve[AUC] > 95%). Kaplan-Meier survival analysis was performed to identify 6 LUAD-SDGs associated with patients' prognosis (P-values < 0.001). Multivariate Cox proportional hazards regression was employed to demonstrate that the six LUAD-SDGs were independent prognostic factors. Then, we used the six overall survival (OS)-related LUAD-SDGs constructing a six-gene signature. Multivariate Cox regression analysis suggested that the six-gene signature was an independent prognostic factor of other clinical variables (hazard ratio [HR] = 1.5098, 95%CI = 1.2996-1.7538, P < 0.0001). Based on our findings, we first presented the LUAD-SDGs for LUAD diagnosis and prognosis. Our results may provide efficient biomarkers to clinical diagnostic and prognostic evaluation in LUAD.

The clinical use of circulating microRNAs as non-invasive diagnostic biomarkers for lung cancers

Many studies have investigated the diagnostic role of circulating microRNAs (miRNAs) in patients with lung cancer; however, the results still remain inconclusive. An updated system review and meta-analysis was necessary to give a comprehensive evaluation of diagnostic role of circulating miRNAs in lung cancer. Eligible studies were searched in electronical databases. The sensitivity and specificity were used to plot the summary receiver operator characteristic (SROC) curve and calculate the area under the curve (AUC). The between-study heterogeneity was evaluated by Q test and I² statistics. Subgroup analyses and meta-regression were further performed to explore the potential sources of heterogeneity. A total of 134 studies from 65 articles (6,919 patients with lung cancer and 7,064 controls) were included for analysis. Overall analysis showed that circulating miRNAs had a good diagnostic performance in lung cancers, with a sensitivity of 0.83, a specificity of 0.84, and an AUC of 0.90. Subgroup analysis suggested that combined miRNAs and Caucasian populations may yield relatively higher diagnostic performance. In addition, we found serum might serve as an ideal material to detecting miRNA as good diagnostic performance. We also found the diagnostic role of miRNAs in early stage lung cancer was still relatively high (the sensitivity, specificity and an AUC of stage I/II was 0.81, 0.82 and 0.88; and for stage I, it was 0.80, 0.81, and 0.88). We also identified a panel of miRNAs such as miR-21-5p, miR-223-3p, miR-155-5p and miR-126-3p might serve as potential biomarkers for lung cancer. As a result, circulating miRNAs, particularly the combination of multiple miRNAs, may serve as promising biomarkers for the diagnosis of lung cancer.

Diagnostic MicroRNA Biomarker Discovery for Non-Small-Cell Lung Cancer Adenocarcinoma by Integrative Bioinformatics Analysis

Lung cancer is the leading cause of cancer death and its incidence is ranked high in men and women worldwide. Non-small-cell lung cancer (NSCLC) adenocarcinoma is one of the most frequent histological subtypes of lung cancer. The aberration profile and the molecular mechanism driving its progression are the key for precision therapy of lung cancer, while the screening of biomarkers is essential to the precision early diagnosis and treatment of the cancer. In this work, we applied a bioinformatics method to analyze the dysregulated interaction network of microRNA-mRNA in NSCLC, based on both the gene expression data and the microRNA-gene regulation network. Considering the properties of the substructure and their biological functions, we identified the putative diagnostic biomarker microRNAs, some of which have been reported on the PubMed citations while the rest, that is, miR-204-5p, miR-567, miR-454-3p, miR-338-3p, and miR-139-5p, were predicted as the putative novel microRNA biomarker for the diagnosis of NSCLC adenocarcinoma. They were further validated by functional enrichment analysis of their target genes. These findings deserve further experimental validations for future clinical application.

Exosomal microRNA in plasma as a non-invasive biomarker for the recurrence of non-small cell lung cancer

Predictive biomarkers for the recurrence of non-small cell lung cancer (NSCLC) in patients who have received curative resection are important for cancer treatment. The functional microRNAs (miRNAs/miRs) in the exosomes of plasma and serum samples are of interest as stable and non-invasive biomarkers for recurrence in cancer patients. The aim of the present study was to clarify the usefulness of plasma exosomal miRNAs as biomarkers for the prediction of recurrence in NSCLC following curative resection. First, microarray-based expression profiling of miRNAs derived from exosomes in the plasma of 6 patients was employed to identify a biomarker that distinguishes between patients with and without NSCLC recurrence. In the miRNA microarray analyses, the exosomal miR-21 and miR-4257 levels of the NSCLC patients showed marked upregulation in those individuals with recurrence compared with those without recurrence and healthy individuals. These two miRNAs were thus selected as recurrence-specific biomarkers and their potential was evaluated in a separate cohort of 195 NSCLC patients. In comparison to the levels in 30 healthy individuals, exosomal miR-21 and miR-4257 levels showed a significant increase in the NSCLC patients (P<0.01). When evaluating the clinicopathological significance of these miRNAs, exosomal miR-21 showed a significant association with tumor size and tumor-node-metastasis (TNM) stage (P<0.05). Exosomal miR-4257 showed a significant association with histological type, lymphatic invasion and TNM stage (P<0.05). The disease-free survival (DFS) rates of high exosomal miR-21 patients were significantly worse than those of low exosomal miR-21 patients (P<0.05), and the DFS rates of patients with high exosomal miR-4257 levels were significantly worse than those with low exosomal miR-4257 levels (P<0.01). In the Cox multivariate analysis, plasma exosomal miR-21 and miR-4257 expression showed a significance association with DFS (P<0.05). These results suggest that plasma exosomal miR-21 and mir-4257 expression has potential as a predictive biomarker for recurrence in NSCLC patients who have received curative resection.

Identification of A Panel of Serum microRNAs as Biomarkers for Early Detection of Lung Adenocarcinoma

Introduction: Since currently no sensitive and specific biomarkers for early detection of lung adenocarcinoma (AD) exist and the majority of AD patients are diagnosed at late stages of disease, the development of effective screening tests for early-stage lung AD is urgently needed. Serum microRNAs (miRNAs) have been documented as novel noninvasive biomarkers in tumor diagnosis; thus, we studied the profile of serum miRNA in AD patients in order to identify the differentially expressed miRNAs as potential biomarkers for early detection of AD.

Patients and Methods: Serum samples were collected from 180 AD patients and 180 age- and sex-matched healthy controls. Serum miRNA profiling was performed by low-density array (LDA) using RNA extracted from blood samples of 20 patients and 20 controls. To validate the selected miRNAs, a stem-loop based RT-qPCR assay was used and serum samples from 160 patients and 160 controls were examined.

Results: Profiling data showed 11 differentially expressed miRNAs in the serum samples from AD patients compared with the controls. Among them, 6 selected miRNAs in AD patients, including miR-103, miR-146a, miR-151, miR-21, miR-221, miR-222, and miR-223, were validated by RT-qPCR. In particular, the top three, miR-146a, miR-222, and miR-223, were confirmed to be significantly expressed in stage I/II AD patients compared with healthy controls.

Conclusion: A panel of miRNAs with miR-146a, miR-222 and miR-223 could be used as potential noninvasive biomarkers for early detection of AD.

A functional variant in miR-155 regulation region contributes to lung cancer risk and survival

Emerging evidence suggested that upregulation of miR-155 could serve as a promising marker for the diagnosis and prognosis of non-small cell lung cancer (NSCLC). In the present study, we genotyped rs767649 (A > T) located in miR-155 regulation region in 1341 cases and 1982 controls, and analyzed the associations of rs767649 with NSCLC risk and survival. Consequently, rs767649 exhibited the significant associations with the risk (adjusted OR = 1.12, 95% CI = 1.01–1.24, P = 0.031) and prognosis of NSCLC (adjusted HR = 1.17, 95% CI = 1.03–1.32, P = 0.014). Meanwhile, rs767649 specifically interacted with radio-chemotherapy (P_int = 0.013), and patients with both the rs767649-TT genotype and radio-chemotherapy had the highest hazard ratio (adjusted HR = 1.65, 95% CI = 1.26–2.16, P < 0.001). Furthermore, using functional assays and The Cancer Genome Atlas (TCGA) Lung Adenocarcinoma (LUAD) dataset, we found that rs767649 variant allele could increase the transcriptional activity of miR-155, which in turn facilitated tumor growth and metastasis by inhibiting HBP1, TJP1, SMAD5 and PRKAR1A expression. Our findings suggested that rs767649 A > T might contribute to the increased risk and poor prognosis of NSCLC, highlighting the importance of rs767649 in the prevention and therapy of NSCLC.

Autophagy inhibition upregulates CD4+ tumor infiltrating lymphocyte expression via miR-155 regulation and TRAIL activation

Chemoresistance is a major challenge in lung cancer treatment. Recent findings have revealed that autophagic mechanism contributes significantly to immunosuppressive related chemoresistance. For that reason, targeting autophagy-related immunosuppression is an important approach to reverse tumor drug resistance. In this study, we report for the first time that autophagy inhibition triggers upregulation of CD4⁺, Foxp3⁺ tumor infiltrating lymphocytes in late metastatic lung cancer tissues. Furthermore, autophagy blockage induces chemosensitization to carboplatin, immune activation and cell cycle arrest. This induction correlated with reduction in expression of drug resistance genes MDR1, MRP1, ABCG2 and ABCC2 along with decreased expression of PD-L1 which is associated with severe dysfunction of tumor specific CD8⁺ T cells. Furthermore, experiments revealed that co-treatment of carboplatin and autophagy inhibitor chloroquine increased lung tissue infiltration by CD4⁺, FoxP3⁺ lymphocytes and antigen-specific immune activation. Subsequent ex vivo experiments showed the activation of carboplatin related TRAIL-dependent apoptosis through caspase 8 and a synergistic role of miR-155 in lung tissue infiltration by CD4⁺, and FoxP3⁺ lymphocytes. Overall, our results indicate that autophagy blockage increases lung cancer chemosensitivity to carboplatin, but also reveal that miR-155 functions as a novel immune system activator by promoting TILs infiltration. These results indicate that targeting of autophagy can prevent cancer related immunosuppression and elucidate immune cell infiltration in tumor microenvironment thus representing a potential therapeutic strategy to inhibit lung cancer progression and metastasis.

New Concepts in Cancer Biomarkers: Circulating miRNAs in Liquid Biopsies

The effective and efficient management of cancer patients relies upon early diagnosis and/or the monitoring of treatment, something that is often difficult to achieve using standard tissue biopsy techniques. Biological fluids such as blood hold great possibilities as a source of non-invasive cancer biomarkers that can act as surrogate markers to biopsy-based sampling. The non-invasive nature of these “liquid biopsies” ultimately means that cancer detection may be earlier and that the ability to monitor disease progression and/or treatment response represents a paradigm shift in the treatment of cancer patients. Below, we review one of the most promising classes of circulating cancer biomarkers: microRNAs (miRNAs). In particular, we will consider their history, the controversy surrounding their origin and biology, and, most importantly, the hurdles that remain to be overcome if they are really to become part of future clinical practice.

The Expression of MicroRNA-155 in Plasma and Tissue Is Matched in Human Laryngeal Squamous Cell Carcinoma

PURPOSE

Tumor-associated microRNAs have been detected in cancer, though whether plasma microRNA-155 (miR-155) could be a potential biomarker for laryngeal squamous cell carcinoma (LSCC) prognosis is unclear. We aimed to determine how miR-155 can be used to predict the clinical characteristics of patients with LSCC and correctly diagnose them.

MATERIALS AND METHODS

We collected tissue samples and peripheral blood samples before and after treatment from 280 LSCC cases and 560 controls. Real-time quantitative reverse transcription PCR was employed in this study to compare the relative expression of miR-155.

RESULTS

A total of 280 LSCC patients and 560 age- and sex-matched controls were included in the study. The miR-155 level was more up-regulated in LSCC tissue than in the non-tumor tissues (13.6 ± 2.4 vs. 3.1 ± 0.80, p<0.001). Additionally, a significantly higher miR-155 level in plasma samples from LSCC patients than in those of the controls (8.9 ± 1.25 vs. 1.8 ± 0.8, p<0.001) was reported. Tissue miR-155 showed an area under the curve (AUC) of 0.933, with a sensitivity of 82.6% and a specificity of 89.2%. The AUC for plasma miR-155 was 0.757, with a sensitivity of 58.4% and a specificity of 69.5%. When early LSCC in TNM I stage was considered, tissue miR-155 showed an area under the curve of 0.804, with a sensitivity of 85.2% and a specificity of 87.3%.

CONCLUSION

The expression of tissue and plasma miR-155 were significantly up-regulated in patients with LSCC. Our work will serve as a basis for further investigation, preferably large-scale validation in clinical trials.

Appraising MicroRNA-155 as a Noninvasive Diagnostic Biomarker for Cancer Detection: A Meta-Analysis

Cancer has been a major public health issue all over the world and cancer patients diagnosed at early stages have a comparatively favorable prognosis. The association between specific dysregulated expressed microRNA-155 (miRNA-155, miR-155) and tumorigenesis has been identified by numerous studies. However, perplexity and inconsistence arise from a wide range of studies due to heterogeneity. Therefore, this meta-analysis was carried out to validate the association between miR-155 and tumorigenesis together with the clinical applicability of miR-155.Relevant studies were searched, identified, and selected from PubMed, Embase, Cochrane, Sinomed, and Wanfang database until July 5, 2015. Then, the sensitivity, specificity, and area under the summary receiver operator characteristic curve (AUC) were calculated to assess the overall performance miR-155 for cancer detection.A total of 25 studies were included in the meta-analysis with a total number of 1896 cancer patients and 1226 healthy controls. The overall sensitivity and specificity was 76.8% (95%CI: 71.1-81.7%) and 82.9% (95% CI: 77.5-87.3%), respectively. In addition, the pooled AUC and partial AUC was 0.867 and 0.718, respectively. Results from subgroup analyses suggested that the diagnostic accuracy of miR-155 in the Caucasian group was significantly higher than that in the Asian group. Similarly, serum sample type may provide better diagnostic value of miR-155 than plasma. Apart from that, miR-155 in breast cancer achieved the highest accuracy compared with miR-155 in other types of cancer.Results from meta-analysis suggested that miR-155 had great potential as a novel noninvasive biomarker for human cancer detection, particularly when breast cancer or Caucasian is involved. However, well-designed cohort or case control studies with large sample size should be implemented to confirm the diagnostic value of miR-155.

Characterization of miR-146a and miR-155 in blood, tissue and cell lines of head and neck squamous cell carcinoma patients and their impact on cell proliferation and migration

PURPOSE

Head and neck squamous cell carcinoma (HNSCC) is one of the most common malignancies worldwide with an unchanged 5-year survival rate during the last decade. To detect reliable prognostic markers and improve patients' outcome in future, the aim of our study was to detect differences in microRNA (miRNA; miR) expression profile and further on to analyze the functional role of selected miRNAs.

METHODS

Blood samples from HNSCC patients and sex- and age-matched healthy volunteers were analyzed by microarrays and validated by quantitative real-time PCR. Data were compared with tumor tissue results and all findings were correlated with clinical parameters. Additionally, the proliferation and migration potential of two cell lines transfected with miRNA mimics and inhibitors for miR-146a and miR-155 were examined.

RESULTS

Initial analysis of blood samples showed no significant differences between the miRNA profile of HNSCC patients and healthy controls (p > 0.05). Interestingly, down-regulation of miR-146a and miR-155 in blood of patients correlated with the occurrence of distant metastasis regarding tumor patients only (p = 0.023 and p = 0.028, respectively). Additionally, our investigations in tissue samples revealed a lower expression of miR-155 in tumor cells (p = 0.003) and a correlation with higher cT-classification for down-regulation of miR-146a (p = 0.005). Moreover, functional assays demonstrated that inhibition of miR-146a and miR-155 promoted dramatically proliferation and migration potential, whereas transfection of both mimics had an inhibitory effect.

CONCLUSIONS

Characterizing the expression of miR-146a and miR-155 and their functional role in tumor biology underlined significantly their proliferation and migration potential suggesting relevance as potential prognostic markers in HNSCC.

MicroRNA-410 promotes cell proliferation by targeting BRD7 in non-small cell lung cancer

miR-410 acts as an oncogene or tumor suppressor gene in some malignancies. However, its role in NSCLC is still unknown. In this study, we showed that the expression of miR-410 was up-regulated in both human NSCLC tissues and cells. Overexpression of miR-410 promoted cell proliferation, migration, and invasion of NSCLC. In addition, bromodomain-containing protein 7 (BRD7) was a direct target of miR-410. MiR-410-mediated downregulation of BRD7 led to increase Akt phosphorylation. Inhibition of Akt phosphorylation can rescue the effect of miR-410 on NSCLC cell. The expression of BRD7 was downregulated in NSCLC and was inversely expressed with miR-410 in NSCLC. Our data provided new knowledge regarding the role of miR-410 in the lung cancer progression.

miR-130a acts as a potential diagnostic biomarker and promotes gastric cancer migration, invasion and proliferation by targeting RUNX3

MicroRNAs (miRNAs) are abnormally expressed in various types of cancer. miR-130a expression and function in gastric cancer has yet to be elucidated. The aim of the present study was to identify the miR-130a expression and function in gastric cancer. miR-130a expression was examined in gastric cancer cell lines and tissues by RT-qPCR. The diagnostic and prognostic significance of miR-130a in gastric cancer was analyzed by receiver-operating characteristic (ROC) curve and Kaplan-Meier analysis. miR130a expression was identified and the diagnostic significance in the serum of gastric cancer patients and healthy controls was analyzed using RT-qPCR and ROC curves, respectively. A target gene for miR-130a was identified using luciferase reporter assays, and gastric cancer tumorigenesis ability was examined by 3-(4,5-dimethylthazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Transwell assays. The results showed that miR‑130a was upregulated in gastric cancer. The low-miR-130a group had significantly improved overall survival compared to the high-miR-130a group. Furthermore, the expression of miR‑130a in plasma in gastric cancer patients was upregulated and diagnostic value for gastric cancer of miR-130a is more effective than the tumor markers carcinoembryonic antigen (CEA) and CA-199. miR-130a directly targeted runt‑related transcription factor 3 (RUNX3) and promoted gastric cancer tumorigenesis by targeting RUNX3. miR-130a may therefore be a useful marker for the diagnosis and prognosis of gastric cancer. Additionally, miR-130a was identified as an oncogene that promotes gastric cancer tumorigenesis by targeting RUNX3.

MicroRNA-155 hallmarks promising accuracy for the diagnosis of various carcinomas: results from a meta-analysis

Background. Recent studies have shown that microRNAs (miRNAs) have diagnostic values in various cancers. This meta-analysis seeks to summarize the global diagnostic role of miR-155 in patients with a variety of carcinomas. Methods. Eligible studies were retrieved by searching the online databases, and the bivariate meta-analysis model was employed to generate the summary receiver operator characteristic (SROC) curve. Results. A total of 17 studies dealing with various carcinomas were finally included. The results showed that single miR-155 testing allowed for the discrimination between cancer patients and healthy donors with a sensitivity of 0.82 (95% CI: 0.73–0.88) and specificity of 0.77 (95% CI: 0.70–0.83), corresponding to an area under curve (AUC) of 0.85, while a panel comprising expressions of miR-155 yielded a sensitivity of 0.76 (95% CI: 0.68–0.82) and specificity of 0.82 (95% CI: 0.77–0.86) in diagnosing cancers. The subgroup analysis displayed that serum miR-155 test harvested higher accuracy than plasma-based assay (the AUC, sensitivity, and specificity were, resp., 0.87 versus 0.73, 0.78 versus 0.74, and 0.77 versus 0.70). Conclusions. Our data suggest that single miR-155 profiling has a potential to be used as a screening test for various carcinomas, and parallel testing of miR-155 confers an improved specificity compared to single miR-155 analysis.

Early Detection of Lung Cancer in Serum by a Panel of MicroRNA Biomarkers

INTRODUCTION

The objective of the study was to develop a panel of microRNAs (miRNAs) as highly sensitive and specific biomarkers for lung cancer early detection.

MATERIALS AND METHODS

The study contained 2 phases: first, preliminary marker selection based on previous reports on the serum of 24 early stage lung cancer patients and 24 healthy control subjects by TaqMan probe-based real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR); and second, validation of miRNA markers on 94 early stage lung cancer, 48 stage III to IV lung cancer, and 111 healthy control serum samples.

RESULTS

A total of 3 miRNAs (miR-125a-5p, miR-25, and miR-126) were selected for further analysis in this study. The combination of the 3 miRNAs could produce 0.936 area under the receiver operating characteristic curve value in distinguishing early stage lung cancer patients from control subjects with 87.5% sensitivity and 87.5% specificity, respectively. The diagnostic value of the miRNA panel in an independent set of lung cancer patients confirmed the sensitivity and specificity.

CONCLUSION

The results demonstrated that the panel of miRNA biomarkers had the potential for the early detection of lung cancer.

Investigation of microRNA-155 as a serum diagnostic and prognostic biomarker for colorectal cancer

The aim of the present study was to explore serum microRNA-155 (miR-155) expression in patients with colorectal cancer (CRC) and examined the potential usefulness of this molecule as a biomarker for diagnosis and prognosis in CRC. Serum samples were obtained between May 2007 and March 2013 from 146 CRC patients and 60 healthy controls. Serum miR-155 expression levels were measured by quantitative real time reverse transcription-polymerase chain reaction (qRT-PCR). Survival curves were obtained using the Kaplan-Meier method and assessed by the log-rank test. The receiver operating characteristic (ROC) curve was used for the prediction of cut-off values of the markers. Serum miR-155 expression level on average was upregulated in CRC patients compared with the matched healthy controls (P < 0.001). ROC curve analysis showed that miR-155 was a useful marker for discriminating cases from healthy controls, with an area under the ROC curve (AUC) of 0.776 (95% confidence interval (CI) 0.714 to 0.837, P < 0.001). Kaplan-Meier analysis with the log-rank test indicated that high serum miR-155 expression had a significant impact on overall survival (38.2 vs. 69.9%; P < 0.001) and progression-free survival (34.8 vs. 66.0%; P < 0.001). In conclusion, the detection of miR-155 levels in the serum might serve as a new tumor biomarker in the diagnosis and assessment of prognosis of CRC.

Clinical use of microRNAs as potential non-invasive biomarkers for detecting non-small cell lung cancer: a meta-analysis

Emerging studies have revealed that microRNA (miRNA) in body fluid may serve as a potential biomarker to detect non-small cell lung cancer (NSCLC). However, the diagnostic accuracy of miRNA for NSCLC detection is still under debate because there is inconsistency in previous studies. Hence, we conducted this meta-analysis to comprehensively evaluate the diagnostic performance of miRNA. A systematic literature search was performed to retrieve relevant articles in PubMed and other databases, and STATA 12.0 (StataCorp, College Station, TX, USA) was used to calculate the pooled parameters. A total of 28 articles involving 2121 NSCLC patients and 1582 healthy controls were included in this meta-analysis. The overall pooled sensitivity and specificity of miRNA were 0.75 and 0.79, respectively. The pooled positive likelihood ratio was 3.6, negative likelihood ratio was 0.32 and diagnostic odds ratio was 12. The area under the curve (AUC) was 0.84. Subgroup and meta-regression analyses established that miRNA assays were more accurate in Caucasian populations (AUC of 0.86, sensitivity of 0.79 and specificity of 0.82, respectively) than in Asian populations (AUC, sensitivity and specificity of 0.83, 0.72 and 0.80, respectively). In addition, the multiple miRNA assays (AUC of 0.89, sensitivity of 0.83 and specificity of 0.82, respectively) showed a higher accuracy than single miRNA assays (AUC, sensitivity and specificity of 0.81, 0.77 and 0.71, respectively) in NSCLC detection. Subgroup analyses based on specimen types suggested that blood-based miRNA (AUC of 0.86, sensitivity of 0.78 and specificity of 0.80, respectively) may have a higher diagnostic accuracy as biomarkers than sputum-based miRNA (AUC of 0.81, sensitivity of 0.69 and specificity of 0.80, respectively). In conclusion, miRNA may serve as a potential biomarker in NSCLS detection, especially the multiple miRNA from blood, with a relatively high diagnostic accuracy.

Next generation sequencing of pancreatic cyst fluid microRNAs from low grade-benign and high grade-invasive lesions

Intraductal papillary mucinous neoplasm (IPMN) is a precursor cystic lesion to pancreatic cancer. With the goal of classifying IPMN cases by risk of progression to pancreatic cancer, we undertook an exploratory next generation sequencing (NGS) based profiling study of miRNAs (miRNome) in the cyst fluids from low grade-benign and high grade-invasive pancreatic cystic lesions. Thirteen miRNAs (miR-138, miR-195, miR-204, miR-216a, miR-217, miR-218, miR-802, miR-155, miR-214, miR-26a, miR-30b, miR-31, and miR-125) were enriched and two miRNAs (miR-451a and miR-4284) were depleted in the cyst fluids derived from invasive carcinomas. Quantitative real-time polymerase chain reaction analysis confirmed that the relative abundance of tumor suppressor miR-216a and miR-217 varied significantly in these cyst fluid samples. Ingenuity Pathway Analysis (IPA) analysis indicated that the genes targeted by the differentially enriched cyst fluid miRNAs are involved in five canonical signaling pathways, including molecular mechanisms of cancer and signaling pathways implicated in colorectal, ovarian and prostate cancers. Our findings make a compelling case for undertaking in-depth analyses of cyst fluid miRNomes for developing informative early detection biomarkers of pancreatic cancer developing from pancreatic cystic lesions.

The potential of genome-wide analyses to improve non-small-cell lung cancer care

SUMMARY 

Genomic technologies have revolutionized the way we study and understand cancer. The advent of next-generation sequencing technology in particular is now starting to change the clinical management of non-small-cell lung cancer. These technologies have helped us to refine prognostication and identify new driver mutations that can allow subselection of patients for therapeutic intervention. However, several limitations and challenges must be overcome before these technologies are widely accepted in diagnostic laboratories. It will be important for clinicians and diagnostic laboratories to consider sample type, analytical platform, cost, data security and ethics, and the bioinformatics challenges associated with 'big data', before widespread integration to the clinic. If these challenges can be overcome, then genomics has the potential to change clinical management of lung cancer.

Integration analysis of microRNA and mRNA expression profiles in human peripheral blood lymphocytes cultured in modeled microgravity

We analyzed miRNA and mRNA expression profiles in human peripheral blood lymphocytes (PBLs) incubated in microgravity condition, simulated by a ground-based rotating wall vessel (RWV) bioreactor. Our results show that 42 miRNAs were differentially expressed in MMG-incubated PBLs compared with 1 g incubated ones. Among these, miR-9-5p, miR-9-3p, miR-155-5p, miR-150-3p, and miR-378-3p were the most dysregulated. To improve the detection of functional miRNA-mRNA pairs, we performed gene expression profiles on the same samples assayed for miRNA profiling and we integrated miRNA and mRNA expression data. The functional classification of miRNA-correlated genes evidenced significant enrichment in the biological processes of immune/inflammatory response, signal transduction, regulation of response to stress, regulation of programmed cell death, and regulation of cell proliferation. We identified the correlation of miR-9-3p, miR-155-5p, miR-150-3p, and miR-378-3p expression with that of genes involved in immune/inflammatory response (e.g., IFNG and IL17F), apoptosis (e.g., PDCD4 and PTEN), and cell proliferation (e.g., NKX3-1 and GADD45A). Experimental assays of cell viability and apoptosis induction validated the results obtained by bioinformatics analyses demonstrating that in human PBLs the exposure to reduced gravitational force increases the frequency of apoptosis and decreases cell proliferation.

Differential expression of miR-125a-5p and let-7e predicts the progression and prognosis of non-small cell lung cancer

Aberrant expression of various microRNAs (miRNA) has shown diagnostic and prognostic significance in non-small cell lung cancer (NSCLC). qRT-PCR analysis confirmed altered expression of miR-125a-5p, let-7e, miR-30a, miR-30e and miR-30e-3p in 70 paired tissue and serum samples from NSCLC patients. The reduced expression of miR-125a-5p, let-7e and miR-30e was strongly associated with NSCLC dedifferentiation. The lost expression of miR-125a-5p and let-7e was associated with shorter overall survival and let-7e was an independent prognostic factor for NSCLC patients. These five miRNA expressions should be further evaluated as biomarkers for the early detection and prognosis of NSCLC patients.