Plasma miR-19b and miR-183 as Potential Biomarkers of Lung Cancer

Size-Coded Hydrogel Microbeads for Extraction-Free Serum Multi-miRNAs Quantifications with Machine-Learning-Aided Lung Cancer Subtypes Classification

Classifying lung cancer subtypes, which are characterized by multi-microRNAs (miRNAs) upregulation, is important for therapy and prognosis evaluation. Liquid biopsy is a promising approach, but the pretreatment of RNA extraction is labor-intensive and impairs accuracy. Here we develop size-coded hydrogel microbeads for extraction-free quantification of miR-21, miR-205, and miR-375 directly from serum. The hydrogel microbead is immobilized with an miRNA capture probe, which well retains target miRNA and provides good nonfouling capability for nonspecific biomolecules in serum. The porous structure of microbeads allows efficient DNA cascade amplification reaction and generates a fluorescence signal. The microbeads are clustered into three groups according to size via flow cytometry sorting, and the group fluorescence is integrated for the corresponding miRNA quantification. With machine-learning-assisted data analysis, it achieves good lung cancer diagnosis accuracy and 80% accuracy for subtype classification for 108 serum samples, including lung cancer patients and healthy controls.

MicroRNA Profiling of Red Blood Cells for Lung Cancer Diagnosis

BACKGROUND

Despite extensive endeavors to establish cell-free circulating biomarkers for lung cancer diagnosis, clinical adoption remains elusive. Noteworthy, emergent evidence suggests the pivotal roles of red blood cells (RBCs) and their derivatives in tumorigenesis, illuminating potential avenues for diagnostic advancements using blood cell-derived microRNAs (miRNAs).

METHODS

We executed microarray analyses on three principal blood cell types-RBCs, peripheral blood mononuclear cells (PBMCs), and neutrophils-encompassing 26 lung cancer patients and 26 healthy controls. Validation was performed using droplet digital PCR within an additional cohort comprising 42 lung cancer and 39 control cases.

RESULTS

Our investigation unearthed distinct miRNA profiles associated with lung cancer across all examined blood cell types. Intriguingly, RBC-miRNAs emerged as potential novel biomarkers for lung cancer, an observation yet to be documented. Importantly, integrating miRNAs from disparate blood cell types yielded a superior diagnostic accuracy for lung cancer over individual cell-type miRNAs. Subsequently, we formulated three diagnostic panels, adeptly discerning non-small cell lung cancer, adenocarcinoma, and squamous cell carcinoma, maintaining consistency across various disease stages.

CONCLUSION

RBC-derived molecules introduce novel cancer biomarkers, and exploiting miRNA profiles across varied blood cell types unveils a promising frontier for lung cancer's early detection and histological classification.

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.

MicroRNAs and 'Sponging' Competitive Endogenous RNAs Dysregulated in Colorectal Cancer: Potential as Noninvasive Biomarkers and Therapeutic Targets

The gastrointestinal (GI) tract in mammals is comprised of dozens of cell types with varied functions, structures, and histological locations that respond in a myriad of ways to epigenetic and genetic factors, environmental cues, diet, and microbiota. The homeostatic functioning of these cells contained within this complex organ system has been shown to be highly regulated by the effect of microRNAs (miRNA). Multiple efforts have uncovered that these miRNAs are often tightly influential in either the suppression or overexpression of inflammatory, apoptotic, and differentiation-related genes and proteins in a variety of cell types in colorectal cancer (CRC). The early detection of CRC and other GI cancers can be difficult, attributable to the invasive nature of prophylactic colonoscopies. Additionally, the levels of miRNAs associated with CRC in biofluids can be contradictory and, therefore, must be considered in the context of other inhibiting competitive endogenous RNAs (ceRNA) such as lncRNAs and circRNAs. There is now a high demand for disease treatments and noninvasive screenings such as testing for bloodborne or fecal miRNAs and their inhibitors/targets. The breadth of this review encompasses current literature on well-established CRC-related miRNAs and the possibilities for their use as biomarkers in the diagnoses of this potentially fatal GI cancer.

High diagnostic value of miRNAs for NSCLC: quantitative analysis for both single and combined miRNAs in lung cancer

BACKGROUND

MicroRNAs (miRNAs) are good candidates as biomarkers for Lung cancer (LC). The aim of this article is to figure out the diagnostic value of both single and combined miRNAs in LC.

METHODS

Normative meta-analysis was conducted based on PRISMA. We assessed the diagnostic value by calculating the combined sensitivity (Sen), specificity (Spe), positive likelihood ratio (PLR), negative likelihood ratio (NLR) and diagnostic odds ratio (DOR) and the area under the curve (AUC) of single and combined miRNAs for LC and specific subgroups.

RESULTS

A total of 80 qualified studies with a total of 8971 patients and 10758 controls were included. In non-small cell lung carcinoma (NSCLC), we involved 20 single-miRNAs and found their Sen, Spe and AUC ranged from 0.52-0.81, 0.66-0.88, and 0.68-0.90, respectively, specially, miR-19 with the maximum Sen, miR-20 and miR-10 with the highest Spe as well as miR-17 with the maximum AUC. Additionally, we detected miR-21 with the maximum Sen of 0.74 [95%CI: 0.62-0.83], miR-146 with the maximum Spe and AUC of 0.93 [95%CI: 0.79-0.98] and 0.89 [95%CI: 0.86-0.92] for early-stage NSCLC. We also identified the diagnostic power of available panel (miR-210, miR-31 and miR-21) for NSCLC with satisfying Sen, Spe and AUC of 0.82 [95%CI: 0.78-0.84], 0.87 [95%CI: 0.84-0.89] and 0.91 [95%CI: 0.88-0.93], and furtherly constructed 2 models for better diagnosis.

CONCLUSIONS

We identified several single miRNAs and combined groups with high diagnostic power for NSCLC through pooled quantitative analysis, which shows that specific miRNAs are good biomarker candidates for NSCLC and further researches needed.

Extracellular vesicles, the cornerstone of next-generation cancer diagnosis?

Cancer has risen up to be a major cause of mortality worldwide over the past decades. Despite advancements in cancer screening and diagnostics, a significant number of cancers are still diagnosed at a late stage with poor prognosis. Hence, the discovery of reliable and accurate methods to diagnose cancer early would be of great help in reducing cancer mortality. Extracellular vesicles (EVs) are phospholipid vesicles found in many biofluids and are released by almost all types of cells. In recent years, using EVs as cancer biomarkers has garnered attention as a novel technique of cancer diagnosis. Compared with traditional tissue biopsy, there are many advantages that this novel diagnostic tool presents - it is less invasive, detects early-stage asymptomatic cancers, and allows for monitoring of tumour progression. As such, EV biomarkers have great potential in improving the diagnostic accuracy of cancers and guiding subsequent therapeutic decisions. Efficient isolation and accurate characterization of EVs are essential for reliable outcomes of clinical application. However, these are complicated by the size and biomolecular diversity of EVs. In this review, we present an analysis and evaluation of the current techniques of EV isolation and characterization, as well as discuss the potential EV biomarkers for specific types of cancer. Taken together, EV biomarkers have a lot of potential as a novel method in cancer diagnostics and diagnosis. However, more work is still needed to streamline the purification, characterization and biomarker identification process to ensure optimal outcomes for 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.

Label-free fluorometric detection of microRNA using isothermal rolling circle amplification generating tandem G-quadruplex

MicroRNAs (miRNAs) play an important role in various biological processes and have been regarded as promising diagnostic biomarkers for solid tumors in the field of clinical diagnostics. In this study, we developed a simple label/quencher-free fluorometric system for sensitive and selective miRNA detection using isothermal gene amplification such as rolling circle amplification generating tandem G-quadruplex DNA structures (GQ-RCA). The closed-circular dumbbell-shaped padlock DNA was designed to be complementary to its corresponding target miRNA. In the presence of the target miRNA, a long stretch of ssDNA with tandem G-quadruplex sequence repeats was readily generated by RCA, initiated by phi29 DNA polymerase through DNA synthesis priming at the 3'-OH of the target miRNA annealed to the padlock DNA. The RCA product harboring tandem G-quadruplex was monitored with fluorophore Thioflavin T (ThT) that emits strong fluorescence only when it intercalates into the G-quadruplex. The GQ-RCA assay enabled us to detect miRNA as low as 4.9 fM with a linear range from 25.6 fM to 80 pM within 0.5 h. In addition, our system was applied to the miRNA samples present in human plasma, showing its potential use in the clinical diagnosis of cancer.

Non-Coding RNAs in Lung Tumor Initiation and Progression

Lung cancer is one of the deadliest forms of cancer affecting society today. Non-coding RNAs, such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), through the transcriptional, post-transcriptional, and epigenetic changes they impose, have been found to be dysregulated to affect lung cancer tumorigenesis and metastasis. This review will briefly summarize hallmarks involved in lung cancer initiation and progression. For initiation, these hallmarks include tumor initiating cells, immortalization, activation of oncogenes and inactivation of tumor suppressors. Hallmarks involved in lung cancer progression include metastasis and drug tolerance and resistance. The targeting of these hallmarks with non-coding RNAs can affect vital metabolic and cell signaling pathways, which as a result can potentially have a role in cancerous and pathological processes. By further understanding non-coding RNAs, researchers can work towards diagnoses and treatments to improve early detection and clinical response.

A systemic approach to screening high-throughput RT-qPCR data for a suitable set of reference circulating miRNAs

Background

The consensus on how to choose a reference gene for serum or plasma miRNA expression qPCR studies has not been reached and none of the potential candidates have yet been convincingly validated. We proposed a new in silico approach of finding a suitable reference for human, circulating miRNAs and identified a new set of endogenous reference miRNA based on miRNA profiling experiments from Gene Expression Omnibus. We used 3 known normalization algorithms (NormFinder, BestKeeper, GeNorm) to calculate a new normalization score. We searched for a universal set of endogenous miRNAs and validated our findings on 2 new datasets using our approach.

Results

We discovered and validated a set of 13 miRNAs (miR-222, miR-92a, miR-27a, miR-17, miR-24, miR-320a, miR-25, miR-126, miR-19b, miR-199a-3p, miR-30b, miR-30c, miR-374a) that can be used to create a reliable reference combination of 3 miRNAs. We showed that on average the mean of 3 miRNAs (p = 0.0002) and 2 miRNAs (p = 0.0031) were a better reference than single miRNA. The arithmetic means of 3 miRNAs: miR-24, miR-222 and miR-27a was shown to be the most stable combination of 3 miRNAs in validation sets.

Conclusions

No single miRNA was suitable as a universal reference in serum miRNA qPCR profiling, but it was possible to designate a set of miRNAs, which consistently contributed to most stable combinations.

Identification of differentially expressed circulating serum microRNA for the diagnosis and prognosis of Indian non-small cell lung cancer patients

PURPOSE

Identification of noninvasive blood-based biomarkers is of utmost importance for the early diagnosis and predicting prognosis of advance stage lung cancer patients. MicroRNAs (miRNAs) has been implicated in numerous diseases, however, their role as diagnostic and prognostic biomarkers in Indian lung cancer patients has not been evaluated yet.

METHODS

For the identification of differentially expressed miRNAs in the serum of non-small cell lung cancer (NSCLC) patients, we performed small RNA sequencing. We validated the expression of 10 miRNAs in 75 NSCLC patients and 40 controls using quantitative reverse transcription polymerase chain reaction (PCR). miRNA expression was correlated with survival and therapeutic response.

RESULTS

We identified 16 differentially expressed miRNAs in the serum of NSCLC patients as compared to controls. We observed significant downregulation of miR-15a-5p, miR-320a, miR-25-3p, miR-192-5p, let-7d-5p, let-7e-5p, miR-148a-3p, and miR-92a-3p in the serum of NSCLC patients. The expression of miR-375 and miR-10b-5p was significantly downregulated in lung squamous cell carcinoma patients than controls. The expression of miR-320a, miR-25-3p, and miR-148a-3p significantly correlated with stage. None of the miRNAs were correlated with survival outcome and therapeutic response.

CONCLUSIONS

We conclude that the relative abundance of miRNAs in serum may be explored for the development of miRNA-based assays for better diagnosis and prognosis of NSCLC. Moreover, further studies are warranted to elucidate the role of some of the less explored miRNAs, such as miR-375 and miR-320a, in the pathogenesis of NSCLC.

Expression and Role of MicroRNA-663b in Childhood Acute Lymphocytic Leukemia and its Mechanism

Recent studies have shown that microRNAs (miRNAs) play a key role in various malignant tumors. MiR-663b has been found to have important roles in several cancers, however, the role of miR-663b in T cell acute lymphocytic leukemia (T-ALL) remains unclear. Therefore, we speculated that miR-663b might also play a crucial role in the development and process of T-ALL. In the present study, we found that miR-663b was up-regulated in the blood of children with T-ALL and T-ALL cell lines. TargetScan and dual luciferase reporter assay results showed that CD99 was a direct target of miR-663b. In order to further study the biological function of miR-663b in the development of T-ALL and to clarify its potential molecular mechanism, we detected the changes in proliferation, apoptosis, migration, and invasion of T-ALL cell line Jurkat before and after miR-663b inhibitor transfection. We found that miR-663b inhibitor inhibited Jurkat cell proliferation and induced apoptosis. In addition, miR-663b inhibitor repressed Jurkat cell migration and invasion. All these effects of miR-663b inhibitor on Jurkat cells were eliminated by CD99-silencing. These results have provided a new theoretical basis and strategy for the diagnosis and treatment of T-ALL.

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.

Plasma MicroRNA as a novel diagnostic

MicroRNAs (miRNAs) are small, single-stranded, endogenous, non-coding RNAs necessary for proper gene expression. Their mechanism of action controls translation by base-pairing with target messenger RNA (mRNAs) thus leading to translation blockage or mRNA degradation. Many studies have shown that miRNAs play pivotal roles in cancer, cardiovascular disease and neurodegenerative disorders. The lack of blood-derived biomarkers and those markers of poor specificity and sensitivity significantly impact the ability to diagnose in general and at early disease stage specifically. As such, new, non-invasive and quantifiable biomarkers are needed. As post-transcriptional regulators of gene expression, miRNAs have been confirmed to be notably stable in cells, tissues and body fluids. These and other advantages make miRNAs ideal candidates as potential biomarkers and early experimental findings support this finding. This review examines the use of miRNAs as biomarkers in cancer, neurodegenerative, cardiovascular and liver disease and viral infection.

Circulating microRNA biomarkers for lung cancer detection in Western populations

Lung cancer (LC) is a leading cause of cancer-related death in the Western world. Patients with LC usually have poor prognosis due to the difficulties in detecting tumors at early stages. Multiple studies have shown that circulating miRNAs might be promising biomarkers for early detection of LC. We aimed to provide an overview of published studies on circulating miRNA markers for early detection of LC and to summarize their diagnostic performance in Western populations. A systematic literature search was performed in PubMed and ISI Web of Knowledge to find relevant studies published up to 11 August 2017. Information on study design, population characteristics, miRNA markers, and diagnostic accuracy (including sensitivity, specificity, and AUC) were independently extracted by two reviewers. Overall, 17 studies evaluating 35 circulating miRNA markers and 19 miRNA panels in serum or plasma were included. The median sensitivity (range) and specificity (range) were, respectively, 78.4% (51.7%-100%) and 78.7% (42.9%-93.5%) for individual miRNAs, and 83.0% (64.0%-100%) and 84.9% (71.0%-100%) for miRNA panels. Most studies incorporated individual miRNA markers as panels (with 2-34 markers), with multiple miRNA-based panels generally outperforming individual markers. Two promising miRNA panels were discovered and verified in prospective cohorts. Of note, both studies exclusively applied miRNA ratios when building up panels. In conclusion, circulating miRNAs may bear potential for noninvasive LC screening, but large studies conducted in screening or longitudinal settings are needed to validate the promising results and optimize the marker panels.

miR-577 suppresses cell proliferation and epithelial-mesenchymal transition by regulating the WNT2B mediated Wnt/β-catenin pathway in non-small cell lung cancer

MicroRNAs (miRNAs/miRs) serve important roles in regulating malignant phenotype in numerous cancers, such as non-small cell lung cancer (NSCLC); however, the role and function of miR-577 in NSCLC remains unknown. In the present study, miR-577 expression levels were observed to be downregulated in NSCLC via reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assay, and inhibited cell proliferation, cell migration and invasion and epithelial-mesenchymal transition progress in NSCLC cells. The predicted target genes of miR-577 were determined by enhanced green fluorescent protein reporter assay, RT-qPCR and western blot analyses. miR-577 was demonstrated to suppress the expression of WNT2B by targeting the 3′-untranslated region of WNT2B mRNA in H522 and A549 cells. WNT2B was upregulated in NSCLC cells as observed via RT-qPCR analysis, and the malignant phenotype of H522 and A549 cells were promoted by WNT2B overexpression. In addition, miR-577 inactivated the Wnt/β-catenin pathway by targeting WNT2B in NSCLC cells. Collectively, miR-577 may function as a suppressor gene by directly downregulatingWNT2B mRNA and protein expression levels in H522 and A549 cells, and may serve important roles in the malignancy of NSCLC.

The prognostic value of microRNA-183 in human cancers: A meta-analysis

BACKGROUND

Several studies have been conducted to explore the prognostic value of miR-183 in different types of cancer; however, their results were controversial. Therefore, the present meta-analysis was conducted to comprehensively evaluate the prognostic value of miR-183 expression level in cancer.

METHODS

A comprehensive literature search was carried out by searching PubMed and EMBASE database between January 1966 and April 2017. Fixed effect and random effect models were used to evaluate the pooled hazard risk (HR) and the relevant 95% confidence intervals (CIs). Subgroup analyses and sensitivity analysis were also carried out.

RESULTS

A total of 12 studies published between 2011 and 2017 were included in the present meta-analysis. The meta-analysis result indicated that there was a significant association between miR-183 expression level and overall survival (HR = 2.642; 95%CI: 2.152-3.245), and there was a significant association between miR-183 expression level and tumor progression (HR = 2.403; 95%CI: 1.267-4.559). In subgroup analysis, we found that high expression level was significantly associated with poor prognosis in most cancers (HR = 2.824, 95%CI: 2.092-3.813); however, low miR-183 level was significantly associated with poor prognosis in melanoma and pancreatic ductal adenocarcinoma (HR = 2.322, 95%CI: 1.337-4.031).

CONCLUSIONS

The results of our meta-analysis indicated that the highly expressed miR-183 might predict poor survival of patients with most cancer types, whereas the downregulated miR-183 level might be associated with poor prognosis in patients with melanoma and pancreatic ductal adenocarcinoma.

Profiling of 179 miRNA Expression in Blood Plasma of Lung Cancer Patients and Cancer-Free Individuals

Lung cancer is one of major cancers, and survival of lung cancer patients is dictated by the timely detection and diagnosis. Cell-free circulating miRNAs were proposed as candidate biomarkers for lung cancer. These RNAs are frequently deregulated in lung cancer and can persist in bodily fluids for extended periods of time, shielded from degradation by membrane vesicles and biopolymer complexes. To date, several groups reported the presence of lung tumour-specific subsets of miRNAs in blood. Here we describe the profiling of blood plasma miRNAs in lung cancer patients, healthy individuals and endobronchitis patients using miRCURY LNA miRNA qPCR Serum/Plasma Panel (Exiqon). From 241 ratios differently expressed between cancer patients and healthy individuals 19 miRNAs were selected for verification using the same platform. LASSO-penalized logistic regression model, including 10 miRNA ratios comprised of 14 individual miRNAs discriminated lung cancer patients from both control groups with AUC of 0.979.

Down-regulation of microRNA-19b in hormone receptor-positive/HER2-negative breast cancer

miR-19b (miR-19b-3p) has been reported to be correlated with either favorable or unfavorable events in several cancers. However, no study has been conducted to evaluate the expression level of miR-19b in patients with breast cancer (BC). This study was aimed to investigate the expression level of miR-19b in human malignant and healthy breast tissues with histopathology of ER+/PR+/HER2-. We performed a miRNA real-time PCR to detect differential expression of miR-19b in 40 BC, including 17 BC with familial background and 23 BC without familial background, and 12 non-tumoral tissues. Moreover, a bioinformatics prediction upon miR-19b functionality in BC cells was performed. The miR-19b expression level was significantly down-regulated in BC, BC with familial background, and BC without familial background compared with its expression in normal tissue (p value, <0.0001; fold change, -7.45; p value, 0.0003; fold change, -6.45; and p value, 0.0005; fold change, -8.41, respectively). Moreover, according to the AUCs (area under curve) of receiver operating characteristic (ROC) curves, miR-19b can significantly distinguish all defined categories. Last, in agreement with our experimental findings, proteoglycans in cancer, pathways in cancer, FoxO signaling pathway, central carbon metabolism in cancer, p53 signaling pathway, transcriptional misregulation in cancer, and prolactin signaling pathway were predicted as miR-19b-related signaling pathways. In summary, down-regulation of miR-19b in BC vs healthy tissue suggests that mir-19b can function as a tumor suppressor. Our results shed additional information on controversial expression pattern of miR-19b depending on different cancer types.

Differentially expressed microRNAs in lung adenocarcinoma invert effects of copy number aberrations of prognostic genes

In many cancers, significantly down- or upregulated genes are found within chromosomal regions with DNA copy number alteration opposite to the expression changes. Generally, this paradox has been overlooked as noise, but can potentially be a consequence of interference of epigenetic regulatory mechanisms, including microRNA-mediated control of mRNA levels.

To explore potential associations between microRNAs and paradoxes in non-small-cell lung cancer (NSCLC) we curated and analyzed lung adenocarcinoma (LUAD) data, comprising gene expressions, copy number aberrations (CNAs) and microRNA expressions. We integrated data from 1,062 tumor samples and 241 normal lung samples, including newly-generated array comparative genomic hybridization (aCGH) data from 63 LUAD samples.

We identified 85 “paradoxical” genes whose differential expression consistently contrasted with aberrations of their copy numbers. Paradoxical status of 70 out of 85 genes was validated on sample-wise basis using The Cancer Genome Atlas (TCGA) LUAD data. Of these, 41 genes are prognostic and form a clinically relevant signature, which we validated on three independent datasets. By meta-analysis of results from 9 LUAD microRNA expression studies we identified 24 consistently-deregulated microRNAs. Using TCGA-LUAD data we showed that deregulation of 19 of these microRNAs explains differential expression of the paradoxical genes.

Our results show that deregulation of paradoxical genes is crucial in LUAD and their expression pattern is maintained epigenetically, defying gene copy number status.

A plasma miRNA signature for lung cancer early detection

The early detection of lung cancer continues to be a major clinical challenge. Using whole-transcriptome next-generation sequencing to analyze lung tumor and the matched noncancerous tissues, we previously identified 54 lung cancer-associated microRNAs (miRNAs). The objective of this study was to investigate whether the miRNAs could be used as plasma biomarkers for lung cancer. We determined expressions of the lung tumor-miRNAs in plasma of a development cohort of 180 subjects by using reverse transcription PCR to develop biomarkers. The development cohort included 92 lung cancer patients and 88 cancer-free smokers. We validated the biomarkers in a validation cohort of 64 individuals comprising 34 lung cancer patients and 30 cancer-free smokers. Of the 54 miRNAs, 30 displayed a significant different expression level in plasma of the lung cancer patients vs. cancer-free controls (all P < 0.05). A plasma miRNA signature (miRs-126, 145, 210, and 205-5p) with the best prediction was developed, producing 91.5% sensitivity and 96.2% specificity for lung cancer detection. Diagnostic performance of the plasma miRNA signature had no association with stage and histological type of lung tumor, and patients' age, sex, and ethnicity (all p > 0.05). The plasma miRNA signature was reproducibly confirmed in the validation cohort. The plasma miRNA signature may provide a blood-based assay for diagnosing lung cancer at the early stage, and thereby reduce the associated mortality and cost.

miR-767-3p Inhibits Growth and Migration of Lung Adenocarcinoma Cells by Regulating CLDN18

Claudin18 (CLDN18) is necessary for intercellular junctions and is reported to be involved in cell migration and metastasis, making it like an oncogene in various cancer types. However, the biological function and regulatory mechanisms of CLDN18 in lung adenocarcinoma are not yet clear. In this study, we found downregulation of miR-767-3p and upregulation of CLDN18 in lung adenocarcinoma tissue and cell lines. In addition, there was a negative correlation between the expression of miR-767-3p and CLDN18 in lung adenocarcinoma. Double luciferase reporter gene analysis showed that miR-767-3p modulates the expression of CLDN18 by binding its 3'-untranslated regions (3'-UTR). Knockdown of CLDN18 results in a decrease in the growth, migration, and invasion of lung adenocarcinoma cells. Although overexpression of miR-767-3p inhibits lung adenocarcinoma cell growth and migration, these effects can be rescued by reexpressing CLDN18. In summary, the data suggest that miR-767-3p inhibits tumor cell proliferation, migration, and invasion by targeting CLDN18, providing a promising therapeutic target for lung adenocarcinoma.

The diagnostic value of serum microRNA-183 and TK1 as biomarkers for colorectal cancer diagnosis

Objective

To evaluate the serum levels of microRNA-183 (miR-183) and thymidine kinase 1 (TK1) in colorectal cancer patients and their clinical value as biomarkers for colorectal cancer auxiliary diagnosis.

Methods

Forty-six pathology confirmed colorectal cancer patients and 46 healthy controls were included in this study. The serum levels of miR-183 and TK1 in colorectal cancer patients and healthy controls were examined by real-time PCR and chemiluminescence detection assay respectively. The diagnostic value of serum miR-183 and TK1 as tumor biomarkers for colorectal cancer detection was evaluated through receiver operating characteristic (ROC) curves.

Results

The median serum relative expression of miR-183 was 1.33 (0.34-5.65) and 0.88 (0.26-4.67) in colorectal cancer patients and healthy controls respectively with significant statistical difference (p<0.05). Using serum miR-183 as the diagnostic reference, the colorectal cancer diagnosis sensitivity, specificity and AUC was 65.22%, 63.04% and 0.69 respectively. The median serum level of TK1 was 3.33 (0.78-5.78) pmol/L and 0.99 (0.34-4.46) pmol/L in colorectal cancer patients and healthy controls respectively with significant statistical difference (p<0.05). The diagnostic sensitivity, specificity and AUC was 84.78%, 78.26% and 0.88 respectively forserum TK1 as reference for colorectal diagnosis. The pearson correlation test was used to evaluate the serum miR-183 and TK1 correlation in colorectal cancer patients. However, no significant correlation between serum miR-183 and TK1 was found in colorectal patients (p>0.05).

Conclusion

Serum levels of miR-183 and TK1 arepotential biomarkers for colorectal cancer auxiliary diagnosis.

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.

miR19b-3p promotes the growth and metastasis of colorectal cancer via directly targeting ITGB8

MicroRNAs (miRNAs) are widely up-regulated or down-regulated in a variety of tumors, including lung cancer, liver cancer, and colorectal cancer (CRC). Furthermore, miRNAs can function as tumor suppressors or proto-oncogenes by controlling the growth and metastasis of cancer cells. In the present study, we found a significant increase in miR19b-3p levels in CRC compared to tumor tissue and revealed the role of miR19b-3p in CRC growth and metastasis. The exogenous overexpression of miR19b-3p induced the proliferation, migration, and invasion of CRC cells in vitro. In addition, the nude mouse xenograft model showed that miR19b-3p overexpression promoted CRC growth and lung metastasis in vivo, whereas silencing miR19b-3p showed opposite results. Mechanistic studies have shown that the integrin beta-8 (ITGB8) transcript is one of the direct targets of miR19b-3p, and the expression of ITGB8 in CRC specimens was positively correlated with miR19b-3p. Finally, ectopic expression of ITGB8 rescued cell proliferation and invasion, which was inhibited by down-regulation of miR19b-3p. In addition, knockdown of ITGB8 neutralized the effects of miR19b-3p overexpression on cell growth and metastasis in CRC cells. Together, these results suggest that the miR19b-3p/ITGB8 axis plays an important role in the growth and metastasis of CRC.

The suppressive role of miR-542-5p in NSCLC: the evidence from clinical data and in vivo validation using a chick chorioallantoic membrane model

Background

Non-small cell lung cancer (NSCLC) has led to the highest cancer-related mortality for decades. To enhance the efficiency of early diagnosis and therapy, more efforts are urgently needed to reveal the origins of NSCLC. In this study, we explored the effect of miR-542-5p in NSCLC with clinical samples and in vivo models and further explored the prospective function of miR-542-5p though bioinformatics methods.

Methods

A total of 125 NSCLC tissue samples were collected, and the expression of miR-542-5p was detected by qRT-PCR. The relationship between miR-542-5p level and clinicopathological features was analyzed. The effect of miR-542-5p on survival time was also explored with K-M survival curves and Cox’s regression. The effect of miR-542-5p on the tumorigenesis of NSCLC was verified with a chick chorioallantoic membrane (CAM) model. The potential target genes were predicted by bioinformatics tools, and relevant pathways were analyzed by GO and KEGG. Several hub genes were validated by Proteinatlas.

Results

The expression of miR-542-5p was down-regulated in NSCLC tissues, and consistent results were also found in the subgroups of adenocarcinoma and squamous cell carcinoma. Down-regulation of miR-542-5p was found to be connected with advanced TNM stage, vascular invasion, lymphatic metastasis and EGFR. Survival analyses showed that patients with lower miR-542-5p levels had markedly poorer prognosis. Both tumor growth and angiogenesis were significantly suppressed by miR-542-5p mimic in the CAM model. The potential 457 target genes of miR-542-5p were enriched in several key cancer-related pathways, such as morphine addiction and the cAMP signaling pathway from KEGG. Interestingly, six genes (GABBR1, PDE4B, PDE4C, ADCY6, ADCY1 and GIPR) from the cAMP signaling pathway were confirmed to be overexpressed in NSCLCs tissues.

Conclusions

This evidence suggests that miR-542-5p is a potential tumor-suppressed miRNA in NSCLC, which has the potential to act as a diagnostic and therapeutic target of NSCLC.

The diagnostic role of plasma circulating precursors of miRNA-944 and miRNA-3662 for non-small cell lung cancer detection

INTRODUCTION

microRNA (miRNA) seem to be most attractive cancer markers due their crucial role in tumor development and possibility of their analysis using liquid biopsy. To date there is little known about role of miRNA precursors (pri-miRNA) in carcinogenesis and their utility as tumor markers.

MATERIAL AND METHODS

miRNA-944 and miRNA-3662 precursors as potential non-small cell lung cancer (NSCLC) markers were analyzed in plasma samples of 56 patients in an early stage of NSCLC and 100 healthy individuals.

RESULTS

Diagnostic test based on two studied markers for stage I-IIIA of the disease allowed to distinguish NSCLC from healthy individuals with 75.7% sensitivity and 82.3% specificity (AUC=0.898). pri-miRNA-944 distinguished SCC from AC with sensitivity of 78.6% and specificity of 91.7% (AUC=0.771), and pri-miRNA-3662 distinguished AC from SCC with 57.1% sensitivity and 90% specificity (AUC=0.845).

CONCLUSION

Circulating pri-miRNA-944 and 3662 can improve non-invasive NSCLC detection of operable stages of SCC and AC. miRNA precursors could be considered as novel potential lung cancer biomarkers.

MiR-542-3p exerts tumor suppressive functions in non-small cell lung cancer cells by upregulating FTSJ2

AIMS

Up-regulation or down-regulation of microRNAs (miRNAs) has been found in non-small cell lung cancer (NSCLC). However, the role and mechanism of regulation of miR-542-3p in NSCLC is still unclear. This study aimed at investigating the primary biological function of miR-542-3p and FTSJ2 in NSCLC tumorigenesis and the correlation of miR-542-3p and FTSJ2 in NSCLC.

MAIN METHODS

Our present results showed that miR-542-3p was down-regulated in NSCLC tissues and cancer cells. Overexpression of miR-542-3p inhibited cell proliferation, cell migration, cell cycle, EMT process and tumor growth in vitro, and induced cell apoptosis by MTT assay, colony formation assay, transwell migration assay, flow cytometry assay, RT-qPCR assay, western blot experiment and vivo model assay; miR-542-3p directly bound to the 3'UTR of FTSJ2 and upregulated FTSJ2 both mRNA and protein level by EGFP reporter assay, RT-qPCR and western blot analysis in NSCLC cells. FTSJ2 also reduced the aggressiveness of NSCLC cells.

KEY FINDINGS

In short, miR-542-3p functions as a suppressor gene by targeting and upregulating FTSJ2, thus inhibiting the malignancy of NSCLC cells.

SIGNIFICANCE

According to the results, miRNA-542-3p and its targeted FTSJ2 may be indispensable as a predictive biomarker of the response to the treatment in patients with NSCLC.

MiR-205 as a promising biomarker in the diagnosis and prognosis of lung cancer

MicroRNA-205 (miR-205) was revealed as a novel diagnostic and prognostic biomarker for lung cancer, but the results in the published papers were inconsistent. This meta-analysis aimed to investigate the diagnostic and prognostic roles of miR-205 in patients with lung cancer. Totally, 16 eligible articles were included, among which 10 articles investigated the diagnostic value of miR-205, 5 articles examined its prognostic values, and 1 article studied both diagnostic and prognostic values. For the diagnostic meta-analysis, the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and the overall area under the curve of miR-205 for patients with lung cancer were 0.88 (95% CI = 0.78 – 0.94), 0.78 (95% CI = 0.66 – 0.86), 4.00 (95% CI = 2.47 – 6.49), 0.16 (95% CI = 0.08 – 0.30), 25.86 (95% CI = 9.29 – 71.95), and 0.90 (95% CI = 0.87 – 0.92), respectively, indicating that miR-205 is a useful biomarker for diagnostic of lung cancer. The subgroup analysis further demonstrated that miR-205 had an excellent overall accuracy for detection with tissue samples compare with blood samples. For the prognostic meta-analysis, the pooled outcome of the disease-free survival and recurrence-free survival analyses revealed that increased miR-205 levels had a protective role in the prognosis of patients with lung cancer (pooled HR = 0.86, 95% CI: 0.78-0.96, z = 2.83, P = 0.005). In conclusion, miR-205 may be a promising biomarker for detection, predicting the recurrence of patients with lung cancer.

Serum miR-200c and miR-371-5p as the Useful Diagnostic Biomarkers and Therapeutic Targets in Kawasaki Disease

Kawasaki disease (KD) has complexly clinical features and laboratory parameters and there is no definitive biomarker for this disease and the therapy of KD also is complex and uncertain. In this study, 102 KD patients and 80 healthy controls were enrolled in this study and the serum microRNAs were detected by qRT-PCR. The results showed that, compared with KD patients with a good response to high-dose intravenous immunoglobulin (IVIG) therapy, serum miR-200c and miR-371-5p were significantly higher in KD patients with no response to IVIG therapy; compared with KD patients not needing plasma exchange, these two microRNAs were also significantly higher in KD patients needing plasma exchange. In addition, combination of serum miR-200c and miR-371-5p reflected obvious separation between KD patients and healthy controls or between KD patients with no response to IVIG therapy and KD patients with good response to IVIG therapy or KD patients needing plasma exchange and KD patients not needing plasma exchange. Finally, both serum miR-200c and miR-371-5p were also significantly lower in KD under different kinds of therapy. Therefore, serum miR-200c and miR-371-5p have ability as the useful diagnostic biomarkers and therapeutic targets in Kawasaki disease.