Prognostic significance of serum miR-17-5p in lung cancer

Exosomal ncRNAs in liquid biopsies for lung cancer

Exosomal non-coding RNAs (ncRNAs) have become essential contributors to advancing and treating lung cancers (LCs). The development of liquid biopsies that utilize exosomal ncRNAs (exo-ncRNAs) offers an encouraging method for diagnosing, predicting, and treating LC. This thorough overview examines the dual function of exo-ncRNAs as both indicators for early diagnosis and avenues for LC treatment. Exosomes are tiny vesicles secreted by various cells, including cancerous cells, enabling connection between cells by delivering ncRNAs. These ncRNAs, which encompass circular RNAs, long ncRNAs, and microRNAs, participate in the modulation of gene expression and cellular functions. In LC, certain exo-ncRNAs are linked to tumour advancement, spread, and treatment resistance, positioning them as promising non-invasive indicators in liquid biopsies. Additionally, targeting these ncRNAs offers potential for innovative treatment approaches, whether by suppressing harmful ncRNAs or reinstating the activity of tumour-suppressing ones. This review emphasizes recent developments in the extraction and analysis of exo-ncRNAs, their practical applications in LC treatment, and the challenges and prospects for translating these discoveries into clinical usage. Through this detailed examination of the current state of the art, we aim to highlight the significant potential of exo-ncRNAs for LC diagnostics and treatments.

Identifying the roles of miR-17 in ciliogenesis and cell cycle

Emerging evidence suggests a significant contribution of primary cilia to cell division and proliferation. MicroRNAs, especially miR-17, contribute to cell cycle regulation and proliferation. Recent investigations have highlighted the dysregulated expression of miR-17 in various malignancies, underlining its potential role in cancer. However, the correlation between primary cilia and miR-17 has yet to be fully elucidated. The present study examines the presence of miR-17 in primary cilia. The miR-17 expression is studied in selected ciliary protein knockdown cells. Using in situ hybridization (ISH), we identified the subcellular localization of miR-17 in both cilium and cell body. We confirmed the importance of miR-17, progesterone receptor membrane component-2 (PGRMC2), and monosialodihexosylganglioside (GM3S) in cilia formation, as shown by the significant reduction in cilia and cilia length in knockdown cells compared to control. We also demonstrated the involvement of PGRMC2, GM3S, polycystin-2 (PKD2), and miR-17 in cellular proliferation and cell growth. Our studies revealed a hyperproliferative effect in the knockdown cells compared to control cells, suggesting the regulatory roles of PGRMC2/GM3S/PKD2/miR-17 in promoting cell proliferation. Overall, our studies conclude that ciliary proteins are involved in cell division and proliferation. We further hypothesize that primary cilia can serve as compartments to store and control genetic materials, further implicating their complex involvement in cellular processes.

Changes in Circulating MicroRNA Levels as Potential Indicators of Training Adaptation in Professional Volleyball Players

The increasing demand placed on professional athletes to enhance their fitness and performance has prompted the search for new, more sensitive biomarkers of physiological ability. One such potential biomarker includes microRNA (miRNA) small regulatory RNA sequences. The study investigated the levels of the selected circulating miRNAs before and after a 10-week training cycle in 12 professional female volleyball players, as well as their association with cortisol, creatine kinase (CK), and interleukin 6 (IL-6), using the qPCR technique. Significant decreases in the miR-22 (0.40 ± 0.1 vs. 0.28 ± 0.12, p = 0.009), miR-17 (0.35 ± 0.13 vs. 0.23 ± 0.08; p = 0.039), miR-24 (0.09 ± 0.04 vs. 0.05 ± 0.02; p = 0.001), and miR-26a (0.11 ± 0.06 vs. 0.06 ± 0.04; p = 0.003) levels were observed after training, alongside reduced levels of cortisol and IL-6. The correlation analysis revealed associations between the miRNAs' relative quantity and the CK concentrations, highlighting their potential role in the muscle repair processes. The linear regression analysis indicated that miR-24 and miR-26a had the greatest impact on the CK levels. The study provides insights into the dynamic changes in the miRNA levels during training, suggesting their potential as biomarkers for monitoring the adaptive responses to exercise. Overall, the findings contribute to a better understanding of the physiological effects of exercise and the potential use of miRNAs, especially miR-24 and miR-26a, as biomarkers in sports science and medicine.

Circulating exosomal miRNAs as a promising diagnostic biomarker in cancer

Cancer belongs to multifactorial diseases characterized by uncontrolled growth and proliferation of abnormal cells. Breast cancer, non-small cell lung cancer, and colorectal cancer are the most frequently diagnosed malignancies with a high mortality rate. These carcinomas typically contain multiple genetically distinct subpopulations of tumor cells leading to tumor heterogeneity, which promotes the aggressiveness of the disease. Early diagnosis is necessary to increase patient progression-free survival. Particularly, miRNAs present in exosomes derived from tumors represent potential biomarkers suitable for early cancer diagnosis. Identification of miRNAs by liquid biopsy enables a personalized approach with the subsequent better clinical management of patients. This review article highlights the potential of circulating exosomal miRNAs in early breast, non-small cell lung, and colorectal cancer diagnosis.

Tumour microenvironment changes after osimertinib treatment resistance in non-small cell lung cancer

BACKGROUND

Growing evidence suggests that acquired resistance to targeted therapy in non-small cell lung cancer patients is linked to the mutual domestication between the tumour and its surrounding microenvironment.

AIM

Our study aims to explore the remodelling of tumour microenvironment after osimertinib treatment resistance.

METHODS

We took RNA-seq-based tumour immune infiltration analysis using the TIMER 2.0. We carried out flow cytometry assay and real-time cell analysis to explore the interaction between tumour cells and immune cells. In addition, we analysed exosomes via miRNA-seq and label-free proteomics.

RESULTS

Immune infiltration estimation showed a significant decrease in the immune score (P < 0.001), microenvironment score (P < 0.001) and CD8+ T cells (P < 0.05), but an increase in M0 macrophages (P < 0.01) at osimertinib resistance compared to pre-treatment patients. It was demonstrated that exosomes from H1975OR cells could be taken up by macrophages and drove their polarisation towards the M2 phenotype, and the polarised M2 macrophages could reduce the inhibitory effect on tumour cell proliferation. Pre-activated peripheral blood mononuclear cells exhibited a more potent killing effect on H1975OR cells. We also detected a decrease in CD4+HLA-DR- T cells and an increase in CD4+PD1+ T cells after being co-cultured with H1975OR derived exosomes or conditioned medium. Further miRNA-seq and proteomics analysis of exosomes demonstrated that mir-1258-3p and miR-17-5p might participate in this interaction.

CONCLUSIONS

An immunosuppressive environment, characterised by decreased T cell infiltration and activation, whereas increased macrophage infiltration and M2 polarisation, was identified at osimertinib resistance. This interaction may be carried out by tumour-derived exosomes.

Cell cycle associated miRNAs as target and therapeutics in lung cancer treatment

Lung cancer is the primary cause of cancer related deaths worldwide. Limited therapeutic options and resistance to existing drugs are the major hindrances to the clinical success of this cancer. In the past decade, several studies showed the role of microRNA (miRNA) driven cell cycle regulation in lung cancer progression. Therefore, these small nucleotide molecules could be utilized as promising tools in lung cancer therapy. In this review, we highlighted the recent advancements in lung cancer therapy using cell cycle linked miRNAs. By highlighting the roles of the specific cell cycle core regulators affiliated miRNAs in lung cancer, we further outlined how these miRNAs can be explored in early diagnosis and treatment strategies to prevent lung cancer. With the provided information from our review, more medical efforts can ensure a potential breakthrough in miRNA-based lung cancer therapy.

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.

BTN3A2 Expression Is Connected With Favorable Prognosis and High Infiltrating Immune in Lung Adenocarcinoma

Background: Butyrophilin subfamily 3 member A2 (BTN3A2) is an important mediator in immune activation, and it is reported to be linked to many cancer progresses. However, the relation with infiltrating immune and prognosis of BTN3A2 in lung adenocarcinoma are not clear.

Methods: In our study, we checked the mRNA expression and protein expression profile of BTN3A2 in lung adenocarcinoma (LUAD) and its relation to clinical outcomes using TIMER and UALCAN databases. In addition, we analyzed the survival of BTN3A2 in LUAD using the Kaplan–Meier Plotter database and PrognoScan database. Moreover, we analyzed gene set enrichment analysis (GSEA) of the BTN3A2. Next, we explored the relation of BTN3A2 expression with the immune infiltration by TIMER. At last, in order to enrich the regulatory mechanism of BTN3A2, we used miRarbase, starbase, and miRDB databases to look for miRNA targets of BTN3A2.

Results: The mRNA along with the protein expression of BTN3A2 in the LUAD group was lower than that in the normal group. In addition, high BTN3A2 expression was connected with good first progression (FP) and overall survival (OS) in LUAD. Then, the GSEA analysis demonstrated that T-cell receptor signaling cascade, B-cell receptor signaling cascade, natural killer cell–mediated cytotoxicity, immune receptor activity, immunological synapse, and T-cell activation were enriched differentially in the BTN3A2 high expression phenotype of LUAD. Moreover, BTN3A2 expression is a remarkable positive correlation with invading levels of tumor purity, B cells, neutrophils, CD4+ T cells, dendritic cells, macrophages, and CD8+ T cells in LUAD, and B cells and dendritic cells were linked with a good prognosis of LUAD. To further enrich the possible regulatory mechanisms of BTN3A2, we analyzed the miRNA targets. The results showed that hsa-miR-17-5p may be miRNA targets of BTN3A2.

Conclusion: Taking together, we provide evidence of BTN3A2 as possible prognosis biomarkers of LUAD. In addition, high BTN3A2 expression in LUAD may influence the prognosis because of immune invasion. Moreover, our findings provide a potential mechanism that hsa-miR-17-5p may be miRNA targets of BTN3A2.

MiRNAs in Lung Cancer: Diagnostic, Prognostic, and Therapeutic Potential

Lung cancer is the dominant emerging factor in cancer-related mortality around the globe. Therapeutic interventions for lung cancer are not up to par, mainly due to reoccurrence/relapse, chemoresistance, and late diagnosis. People are currently interested in miRNAs, which are small double-stranded (20–24 ribonucleotides) structures that regulate molecular targets (tumor suppressors, oncogenes) involved in tumorigeneses such as cell proliferation, apoptosis, metastasis, and angiogenesis via post-transcriptional regulation of mRNA. Many studies suggest the emerging role of miRNAs in lung cancer diagnostics, prognostics, and therapeutics. Therefore, it is necessary to intensely explore the miRNOME expression of lung tumors and the development of anti-cancer strategies. The current review focuses on the therapeutic, diagnostic, and prognostic potential of numerous miRNAs in lung cancer.

Overexpression of miR-17 predicts adverse prognosis and disease recurrence for acute myeloid leukemia

Background

The clinical significance of miR-17 in patients with acute myeloid leukemia (AML) remains unknown.

Methods

Real-time quantitative reverse transcription-polymerase chain reaction (qPCR) was performed to detect the miR-17 expression in 115 de novo AML patients, 31 patients at complete remission (CR) time, 8 patients at relapse time and 30 normal controls.

Results

MiR-17 was upregulated in de novo AML compared with normal controls. Patients with high expression of miR-17 had less CEBPA double mutation, less favorable ELN-risk and lower CR rate. The level of miR-17 was significantly decreased at CR phase and was returned to primary level even higher when in relapse phase. In addition, Cox regression analysis revealed that miR-17 expression retained independent prognostic significance for overall survival (OS). Moreover, the gene-expression profile analysis of miR-17 in AML obtained from TCGA database was involved in multiple biological functions and signal pathways. Among the differential expressed genes (DEGs), we identified FGL2, PLAUR, SLC2A3, GPR65, CTSS, TLR7, S1PR3, OGFRL1, LILRB1, IL17RA, SIGLEC10, SLAMF7, PLXDC2, HPSE, TCF7 and MYCL as potential direct targets of miR-17 according to in silico analysis.

Conclusions

High expression of miR-17 in de novo AML patients pointed to dismal clinical outcome and disease recurrence, which could serve as novel prognostic biomarker for AML patients.

MicroRNA-17-92a-1 Host Gene (MIR17HG) Expression Signature and rs4284505 Variant Association with Alopecia Areata: A Case-Control Study

Accumulating evidence indicates the implication of microRNAs (miRs) in cutaneous and hair follicle immunobiology. We evaluated, for the first time, the miR-17-92a-1 cluster host gene (MIR17HG) expression in peripheral blood of 248 unrelated alopecia areata (AA) patients compared to 244 matched controls using Real-Time qPCR. We also tested its association with different rs4284505A>G genotypes (based on TaqMan allelic discrimination PCR) and the available clinical data. The adjusted odds ratio (OR) and 95% confidence interval (CI) were calculated for each genetic association model. The upregulation of miR-17 was observed in the serum of patients with alopecia compared to controls (p-value = 0.004). The ROC curve showed high diagnostic performance of miR-17 in differentiating between patients and controls (AUC = 0.85, p-value < 0.001). rs4284505*A/G heterozygotes were more susceptible to the disease (OR = 1.57, 95% CI = 1.01−2.45) under the over-dominant model. Interestingly, patients with the rs4284505*G/G genotype had a higher level of miR-17 than those with the A/A and A/G genotypes. The G/G genotype was associated with the severe phenotype (p-value = 0.038). A/G carriers were the youngest (p-value < 0.001), had more frequent scalp infection (p-value = 0.006), exhibited the worst dermatology life quality index score (p-value = 0.037), and responded less to treatment (p-value = 0.033). In conclusion, MIR17HG expression and the rs4284505 variant were significantly associated with AA and could play a role in pathogenesis and phenotype in the Egyptian population. Further multi-center studies in other ethnicities are warranted to replicate the findings.

Spectrum of microRNAs and their target genes in cancer: intervention in diagnosis and therapy

Till date, several groups have studied the mechanism of microRNA (miRNA) biogenesis, processing, stability, silencing, and their dysregulation in cancer. The miRNA coding genes recurrently go through abnormal amplification, deletion, transcription, and epigenetic regulation in cancer. Some miRNAs function as tumor promoters while few others are tumor suppressors based on the transcriptional regulation of target genes. A review of miRNAs and their target genes in a wide range of cancers is attempted in this article, which may help in the development of new diagnostic tools and intervention therapies. The contribution of miRNAs for drug sensitivity or resistance in cancer therapy and opportunities of miRNAs in cancer prognosis or diagnosis and therapy is also presented in detail.

Diagnostic value of PPARδ and miRNA-17 expression levels in patients with non-small cell lung cancer

The PPARδ gene codes protein that belongs to the peroxisome proliferator-activated receptor (PPAR) family engaged in a variety of biological processes, including carcinogenesis. Specific biological and clinical roles of PPARδ in non-small cell lung cancer (NSCLC) is not fully explained. The association of PPARα with miRNA regulators (e.g. miRNA-17) has been documented, suggesting the existence of a functional relationship of all PPARs with epigenetic regulation. The aim of the study was to determine the PPARδ and miR-17 expression profiles in NSCLC and to assess their diagnostic value in lung carcinogenesis. PPARδ and miR-17 expressions was assessed by qPCR in NSCLC tissue samples (n = 26) and corresponding macroscopically unchanged lung tissue samples adjacent to the primary lesions served as control (n = 26). PPARδ and miR-17 expression were significantly lower in NSCLC than in the control (p = 0.0001 and p = 0.0178; respectively). A receiver operating characteristic (ROC) curve analysis demonstrated the diagnostic potential in discriminating NSCLC from the control with an area under the curve (AUC) of 0.914 for PPARδ and 0.692 for miR-17. Significant increase in PPARδ expression in the control for current smokers vs. former smokers (p = 0.0200) and increase in miR-17 expression in control tissue adjacent to adenocarcinoma subtype (p = 0.0422) were observed. Overexpression of miR-17 was observed at an early stage of lung carcinogenesis, which may suggest that it acts as a putative oncomiR. PPARδ and miR-17 may be markers differentiating tumour tissue from surgical margin and miR-17 may have diagnostic role in NSCLC histotypes differentiation.

Comprehensive Pan-Cancer Analysis of the Prognostic and Immunological Roles of the METTL3/lncRNA-SNHG1/miRNA-140-3p/UBE2C Axis

Growing evidence has demonstrated that UBE2C plays a critical role in cancer progression, but there is no study focusing on the prognosis, upstream regulation mechanism, and immunological roles of UBE2C across diverse tumor types. In this study, we found that UBE2C was elevated in this human pan-cancer analysis, and high expression of UBE2C was correlated with poor prognosis. In addition, UBE2C expression was markedly associated with tumor mutation burden (TMB), microsatellite instability (MSI), immune cell infiltration, and diverse drug sensitivities. Finally, we showed that the METTL3/SNHG1/miRNA-140-3p axis could potentially regulate UBE2C expression. N(6)-Methyladenosine (m6A) modifications improved the stability of methylated SNHG1 transcripts by decreasing the rate of RNA degradation, which lead to upregulation of SNHG1 in non-small cell lung cancer (NSCLC). In vitro functional experiments showed that SNHG1, as a competing endogenous RNA, sponges miR-140-3p to increase UBE2C expression in NSCLC cell lines. Our study elucidates the clinical importance and regulatory mechanism of the METTL3/SNHG1/miRNA-140-3p/UBE2C axis in NSCLC and provides a prognostic indicator, as well as a promising therapeutic target for patients with NSCLC.

microRNA-based diagnostic and therapeutic applications in cancer medicine

It has been almost two decades since the first link between microRNAs and cancer was established. In the ensuing years, this abundant class of short noncoding regulatory RNAs has been studied in virtually all cancer types. This tremendously large body of research has generated innovative technological advances for detection of microRNAs in tissue and bodily fluids, identified the diagnostic, prognostic, and/or predictive value of individual microRNAs or microRNA signatures as potential biomarkers for patient management, shed light on regulatory mechanisms of RNA-RNA interactions that modulate gene expression, uncovered cell-autonomous and cell-to-cell communication roles of specific microRNAs, and developed a battery of viral and nonviral delivery approaches for therapeutic intervention. Despite these intense and prolific research efforts in preclinical and clinical settings, there are a limited number of microRNA-based applications that have been incorporated into clinical practice. We review recent literature and ongoing clinical trials that highlight most promising approaches and standing challenges to translate these findings into viable microRNA-based clinical tools for cancer medicine. This article is categorized under: RNA in Disease and Development > RNA in Disease.

Cucurbitacin B enhances apoptosis in gefitinib resistant non‑small cell lung cancer by modulating the miR‑17‑5p/STAT3 axis

Tyrosine kinase inhibitors, such as gefitinib, are currently widely used as targeted therapeutics for non-small cell lung cancer (NSCLC). Although drug resistance has become a major obstacle to successful treatment, mechanisms underlying resistance to gefitinib remain unclear. Therefore, the present study aimed to investigate the impact of adjunctive cucurbitacin B (CuB) on gefitinib resistance (GR) in the PC9 cell line, including identifying underlying mechanisms. Reverse transcription-quantitative PCR demonstrated significant downregulation of microRNA (miR)-17-5p expression in GR PC9 cells (PC9/GR), and this could be reversed by CuB. During combination treatment with CuB and gefitinib at IC₂₅, PC9/GR cell proliferation was downregulated, and apoptosis was upregulated. The presence of a miR-17-5p inhibitor negated the effects of CuB and gefitinib, whereas the presence of a miR-17-5p mimic enhanced them. Luciferase assays demonstrated that the hypothetical target gene, signal transducer and activator of transcription 3 (STAT3), was directly targeted by miR-17-5p. Moreover, significant elevation of the STAT3 protein and phosphorylation levels in PC9/GR cells was reversed by the addition of CuB, despite a lack of change in STAT3 transcription level. During combined treatment with CuB and gefitinib at IC₂₅, the STAT3 protein expression was negatively associated with the expression of miR-17-5p. Overexpression of STAT3 increased proliferation and decreased apoptosis and the protein levels of apoptosis-related factors cleaved caspase-3 and cleaved caspase-9 of PC9/GR cells. Findings indicated that STAT3 protein and phosphorylation levels became elevated in response to gefitinib, and that CuB-induced miR-17-5p expression led to STAT3 degradation, thereby ameliorating GR. In summary, CuB reduced the proliferation of GR PC9 cells by modulating the miR-17-5p/STAT3 axis, and may represent a promising potential novel strategy for the reversal of GR.

New biomarkers in peripheral blood of patients with ovarian cancer: high expression levels of miR-16-5p, miR-17-5p, and miR-638

OBJECTIVES

Ovarian cancer is one of the most fatal gynecologic malignities. miR-16-5p, miR-17-5p, and miR-638 genes were found to have been associated with ovarian cancer in accordance with the data obtained from the previous microarray research performed by Tuncer et al. (J Ovarian Res 13(1):99, 2020). The expression levels of these miRNAs in the peripheral blood samples of 142 ovarian cancer patients, and 97 healthy controls were investigated for performing the validation, and to identify whether these genes were the possible biomarkers to be used in the early diagnosis of high-risk ovarian cancer patients, and in the prognosis of patients.

METHODS

The miRNA expression analysis was performed using the miRNA-specific cDNA synthesis, and real-time PCR methods following the RNA isolation from the peripheral blood lymphocytes.

RESULTS

miR-16-5p, miR-17-5p, and miR-638 miRNA gene expression levels were found to have twofold higher expression levels in patient groups compared with the gene expression levels in healthy controls, and were statistically significant (p < 0.05). In addition, the comparison of the miRNA expression levels with the clinical data of patients showed that there was a significant difference with smoking history and the increased expression level of miR-17-5 (p: 0.007). There was a significant difference between the increased expression level of miR-638 with the locally advanced stage, and abdominal/pelvic metastatic patients (p: 0.03).

CONCLUSIONS

The obtained data suggest that miR-16-5p, miR-17-5p, and miR-638 molecules might be the noninvasive biomarkers in identifying the ovarian cancer. However, the investigation and monitoring of the changeability of these biomarkers in benign ovarian diseases, and during the treatment must be performed in future studies for identifying the accurate diagnostic, and prognostic features of miRNAs.

LKB1 Down-Modulation by miR-17 Identifies Patients With NSCLC Having Worse Prognosis Eligible for Energy-Stress-Based Treatments

INTRODUCTION

Preclinical models recently unveiled the vulnerability of LKB1/KRAS comutated NSCLC to metabolic stress-based treatments. Because miR-17 is a potential epigenetic regulator of LKB1, we hypothesized that wild-type LKB1 (LKB1^WT) NSCLC with high miR-17 expression may be sensitive to an energetic stress condition, and eligible for metabolic frailties-based therapeutic intervention.

METHODS

We took advantage of NSCLC cell lines with different combinations of KRAS mutation and LKB1 deletion and of patient-derived xenografts (PDXs) with high (LKB1^WT/miR-17 high) or low (LKB1^WT/miR-17 low) miR-17 expression. We evaluated LKB1 pathway impairment and apoptotic response to metformin. We retrospectively evaluated LKB1 and miR-17 expression levels in tissue specimens of patients with NSCLC and PDXs. In addition, a lung cancer series from The Cancer Genome Atlas data set was analyzed for miR-17 expression and potential correlation with clinical features.

RESULTS

We identified miR-17 as an epigenetic regulator of LKB1 in NSCLC and confirmed targeting of miR-17 to LKB1 3' untranslated region by luciferase reporter assay. We found that miR-17 overexpression functionally impairs the LKB1/AMPK pathway. Metformin treatment prompted apoptosis on miR-17 overexpression only in LKB1^WT cell lines, and in LKB1^WT/miR-17 high PDXs. A retrospective analysis in patients with NSCLC revealed an inverse correlation between miR-17 and LKB1 expression and highlighted a prognostic role of miR-17 expression in LKB1^WT patients, which was further confirmed by The Cancer Genome Atlas data analysis.

CONCLUSIONS

We identified miR-17 as a mediator of LKB1 expression in NSCLC tumors. This study proposes a miR-17 expression score potentially exploitable to discriminate LKB1^WT patients with NSCLC with impaired LKB1 expression and poor outcome, eligible for energy-stress-based treatments.

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.

Prognostic Value of microRNA-221/2 and 17-92 Families in Primary Glioblastoma Patients Treated with Postoperative Radiotherapy

MicroRNAs (miRs) are non-coding master regulators of transcriptome that could act as tumor suppressors (TSs) or oncogenes (oncomiRs). We aimed to systematically investigate the relevance of miRs as prognostic biomarkers in primary glioblastoma multiforme (GBM) treated with postoperative radio(chemo)therapy (PORT). For hypothesis generation, tumor miR expression by Agilent 8x15K human microRNA microarrays and survival data from 482 GBM patients of The Cancer Genome Atlas (TCGA cohort) were analyzed using Cox-PH models. Expression of candidate miRs with prognostic relevance (miR-221/222; miR-17-5p, miR-18a, miR-19b) was validated by qRT-PCR using Taqman technology on an independent validation cohort of GBM patients (n = 109) treated at Heidelberg University Hospital (HD cohort). In TCGA, 50 miRs showed significant association with survival. Among the top ranked prognostic miRs were members of the two miR families miR-221/222 and miR-17-92. Loss of miR-221/222 was correlated with improved prognosis in both cohorts (TCGA, HD) and was an independent prognostic marker in a multivariate analysis considering demographic characteristics (age, sex, Karnofsky performance index (KPI)), molecular markers (O-6-methylguanine-DNA methyltransferase (MGMT) methylation, IDH mutation status) and PORT as co-variables. The prognostic value of miR-17-92 family members was ambiguous and in part contradictory by direct comparison of the two cohorts, thus warranting further validation in larger prospective trials.

MiR-17 Knockdown Promotes Vascular Smooth Muscle Cell Phenotypic Modulation Through Upregulated Interferon Regulator Factor 9 Expression

BACKGROUND

MiR-17 is a small noncoding RNA that plays an important role in the development of tumorgenesis, which recently has emerged to be involved in regulation of inflammatory responses and angiogenesis. However, the effect and underlying mechanism of miR-17 on vascular smooth muscle cell (VSMC) phenotypic modulation have not been investigated.

METHODS AND RESULTS

In the current study, we observed that miR-17 expression tested by real-time polymerase chain reaction (RT-PCR) was downregulated in VSMCs administrated with platelet-derived growth factor-BB stimulation and carotid arteries subjected to wire injury, which were accompanied with decreased VSMC differentiation markers. Loss-of-function strategy demonstrated that miR-17 knockdown promoted VSMC phenotypic modulation characterized as decreased VSMC differentiation marker genes, increased proliferated and migrated capability of VSMC examined by RT-PCR and western blot analysis. Mechanistically, the bioinformatics analysis and luciferase assay demonstrated that miR-17 directly targeted Interferon Regulator Factor 9 (IRF9) and the upregulated IRF9 expression was responsible for the promoted effect miR-17 knockdown on VSMC phenotypic modulation.

CONCLUSIONS

Taken together, our results demonstrated that miR-17 knockdown accelerated VSMC phenotypic modulation partially through directly targeting to IRF9, which suggested that miR-17 may act as a novel therapeutic target for intimal hyperplasia management.

Emerging role of miRNAs as liquid biopsy markers for prediction of glioblastoma multiforme prognosis

Serum miRNAs (miRs) have gained consideration as encouraging molecular markers for cancer diagnosis and prediction of prognosis. The authors aimed to identify the exact role of miR-17-5p, miR-125b, and miR-221 among glioblastoma multiforme (GBM) patients before and after standard treatment, and correlate their expression with survival pattern. The study included 25 GBM patients and 20 healthy controls. Serum miR-17-5p, miR-125b, and miR-221 expression were analyzed before and after treatment using quantitative real-time polymerase chain reaction (qPCR). The diagnostic efficacy for the tested miRs was evaluated using the receiver operating characteristic (ROC) curve, and the relation of miRs expression versus clinical criteria for GBM was assessed. Patients' survival patterns were examined versus miRs expression levels. A significant difference was reported between miRs expression among the enrolled individuals. Both miR-17-5p and miR-221 reported significant elevations in GBM patients who: are above 60 years old, underwent biopsy resection, have a non-frontal lesion, with tumor size above 5 cm, and with performance status equals 2 according to the Eastern Cooperative Oncology Group (ECOG) Performance Status. With regard to miR-125b, a significant difference was detected according to surgery strategy, primary lesion of the tumor, and ECOG status. MiRs levels were significantly decreased for GBM patients after treatment. Survival patterns demonstrated an increase in miR-17-5p, miR-125b, and miR-221 in GBM patients with worse progression-free survival and among those with worse overall survival. Detection of serum miR-17-5p, miR-125b, and miR-221 aids in the prediction of prognosis and response to treatment strategy for GBM patients.

Aberrant methylation and microRNA-target regulation are associated with downregulated NEURL1B: a diagnostic and prognostic target in colon cancer

BACKGROUND

Aberrant methylation and miRNA-target-gene regulation function as important mechanisms for gene inactivation in colon carcinogenesis. Although a serious of molecular events (such as aberrant alterations of genomics and epigenetics) have been identified to be related to prognostic in colon cancer (CC) patients, beneficial biomarkers for early diagnosis and prognostic evaluation remain largely unknown.

METHODS

In our study, the role of NEURL1B, including gene expression analysis, methylation characteristic, miRNA-target regulation, diagnostic and prognostic significance, were evaculated using multiple bioinformatic tools based on TCGA database and clinical samples.

RESULTS

Our data showed that NEURL1B was aberrantly downregulated in CC, regardless of the mRNA level or protein level. Moreover, ROC curve and multivariate Cox regression analysis demonstrated that NEURL1B was a diagnostic and independent prognostic facter for CC patients. Of interest, methylation of NEURL1B was also high and closely associated with poor survival in CC. In addition, multiple NEURL1B-target miRNAs were found to be overexpressed in CC tissues. Thus, our findings suggested that NEURL1B participated in the pathological processes of CC as a tumor suppressor gene. Double management, including DNA methylation modification and miRNA-target regulation, were considered to be related to the downregulation of NEURL1B. Importantly, there existing be an significant intersection between miRNAs-target pathways and NEURL1B-target pathways, suggesting that miR-17 and miR-27a might promote tumor cell malignant property by targeting NEURL1B degradation via the activation of PI3K/AKT signaling pathway.

CONCLUSIONS

Taking together, the first investigation of NEURL1B in CC provide us a strong evidences that it might be served as a potential biomarkers for early diagnosis and prognostic evaluation in CC.

miRNA-22 as a Candidate Diagnostic Biomarker for Coronary Slow Flow

Background

Coronary slow flow (CSF) refers to the phenomenon of delayed distal flow in the absence of lesions detected on coronary angiography. Although the detection rate of CSF has been increasing in clinical practice, early diagnosis is difficult and the factors contributing to this condition remain unclear. Given the increasing demonstration of the roles of microRNAs (miRNAs) in disease and as diagnostic biomarkers, the aim of this study was to analyze the expression of serum miRNA-22 in patients with CSF detected using coronary angiography and its diagnostic efficacy.

Methods and Results

A retrospective analysis including 44 patients with CSF and 42 patients with normal coronary flow (control group) was conducted. Additionally, all included patients either did not have visually estimated coronary artery stenosis or had <50% stenosis. Plasma samples were collected from patients in these two groups, and the levels of miRNA-22 were detected. The receiver operating characteristic (ROC) curve was plotted to evaluate the diagnostic efficiency of serum miRNA-22 in the context of CSF.

Results

The expression of serum miRNA-22 was significantly higher in the CSF patients than in the control subjects (P < 0.0001). The area under the ROC curve for miRNA-22 in diagnosing CSF was 0.8293 (95% confidence interval: 0.7313–0.9272), with a sensitivity of 75.0% and specificity of 88.1%.

Conclusions

The expression of serum miRNA-22 in CSF is upregulated compared to that in subjects with normal coronary flow and shows relatively high clinical diagnostic efficiency, suggesting a new potential biomarker for the early diagnosis of CSF.

Circulating MicroRNAs as Potential Biomarkers for Lung Cancer

Lung cancer is the number one cause of cancer-related mortality worldwide. To improve disease outcome, it is crucial to implement biomarkers into the clinics which assist physicians in their decisions regarding diagnosis, prognosis, as well as prediction of treatment response. Liquid biopsy offers an opportunity to obtain such biomarkers in a minimal invasive manner by retrieving tumor-derived material from body fluids of the patient. The abundance of circulating microRNAs is known to be altered in disease and has therefore been studied extensively as a cancer biomarker. Circulating microRNAs present a variety of favorable characteristics for application as liquid biopsy-based biomarkers, including their high stability, relatively high abundance, and presence is nearly all body fluids. Although the application of circulating microRNAs for the management of lung cancer has not entered the clinics yet, several studies showed their utility for diagnosis, prognosis, and efficacy prediction of various treatment strategies, including surgery, radio-/chemotherapy, as well as targeted therapy. To compensate for their limited tumor specificity, several microRNAs are frequently combined into microRNA panels. Moreover, the possibility to combine single microRNAs or microRNA panels with tumor imaging or other cancer-specific biomarkers has the potential to increase specificity and sensitivity and could lead to the clinical application of novel multi-marker combinations.

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.

CircMTO1 inhibits liver fibrosis via regulation of miR-17-5p and Smad7

Circular RNAs (circRNAs), often dysregulated in a variety of human diseases, participate in the initiation and development of cancers. Recently, circMTO1 (a circRNA derived from MTO1 gene), identified as a tumor suppressor, has been shown to contribute to the suppression of hepatocellular carcinoma. The present study aimed to explore the clinical significance and roles of circMTO1 in liver fibrosis. Here, we found that serum circMTO1 was significantly down-regulated in chronic hepatitis B (CHB) patients. Interestingly, serum circMTO1 was negatively correlated with fibrosis stages as well as HAI scores. Receiver operating characteristic curve analysis revealed that serum circMTO1 may serve as a diagnostic biomarker for liver fibrosis in CHB patients. Notably, overexpression of circMTO1 led to the suppression of transforming growth factor-β1-induced hepatic stellate cells (HSCs) activation. Bioinformatic analysis and luciferase activity assays indicated that circMTO1 was a target of mircoRNA-17-5p (miR-17-5p). Data from RNA pull-down assay further confirmed that circMTO1 interacted with miR-17-5p. The inhibitory effects of circMTO1 on HSC activation were suppressed by miR-17-5p mimics. Further studies showed that Smad7 was a target of miR-17-5p. Moreover, circMTO1-inhibited HSC activation was also blocked down by loss of Smad7. Taken together, we demonstrate that circMTO1 inhibits liver fibrosis via regulation of miR-17-5p and Smad7, and serum circMTO1 may be a novel promising biomarker of liver fibrosis.

LncRNA H19 interacted with miR-130a-3p and miR-17-5p to modify radio-resistance and chemo-sensitivity of cardiac carcinoma cells

The current investigation explored the synthetic contribution of lncRNA H19, miR-130a-3p, and miR-17-5p to radio-resistance and chemo-sensitivity of cardiac cancer cells. Totally 284 human cardiac cancer tissues were gathered, and they have been pathologically diagnosed. The cardiac cancer cells were isolated with utilization of the mechanic method. Moreover, cisplatin, adriamycin, mitomycin, and 5-fluorouracil were designated as the chemotherapies, and single-dose X-rays were managed as the radiotherapy for cardiac cancer cells. We also performed luciferase reporter gene assay to verify the targeted relationship between H19 and miR-130a-3p, as well as between H19 and miR-17-5p. Finally, mice models were established to examine the functions of H19, miR-130a-3p, and miR-17-5p on the development of cardiac cancer. The study results indicated that H19, miR-130a-3p, and miR-17-5p expressions within cardiac cancer tissues were significantly beyond those within adjacent nontumor tissues (P < 0.05), and H19 expression was positively correlated with both miR-130a-3p (r_s  = 0.43) and miR-17-5p (r_s  = 0.49) expressions. The half maximal inhibitory concentrations (IC50) of cisplatin, adriamycin, mitomycin, and 5-fluorouracil for cardiac cancer cells were, respectively, determined as 2.01 μg/mL, 8.35 μg/mL, 24.44 μg/mL, and 166.42 μg/mL. The overexpressed H19, miR-130a-3p, and miR-17-5p appeared to improve the survival rate and viability of cardiac cancer cells that were exposed to chemotherapies and X-rays (all P < 0.05). It was also drawn from luciferase reporter gene assay that H19 could directly target miR-130a-3p and miR-17-5p, thereby modifying the sensitivity of cardiac cancer cells to drugs and X-rays (P < 0.05). Finally, the mice models also produced larger tumor size and higher tumor weight, when H19, miR-130a-3p, or miR-17-5p expressions were up-regulated within them (P < 0.05). In conclusion, H19 could act on miR-130a-3p or miR-17-5p to alter the radio- and chemo-sensitivities of cardiac cancer cells, helping to improve the radio-/chemotherapies for cardiac cancer.

Prognostic value of miR-17-5 p in gastrointestinal cancers: a systematic review and meta-analysis

BACKGROUND

There are accumulating studies investigating the aberrant expression of microRNAs in tumor patients. As an important member of miR-17/92 cluster, miR-17-5 p has been identified as a potential prognostic factor for survival in tumor patients. We conducted this meta-analysis aimed to assess the effect of miR-17-5 p as a prognostic biomarker for gastrointestinal tumor patients.

MATERIALS AND METHODS

Eligible studies were enrolled by searching the online databases of PubMed, Embase, Web of Science, China National Knowledge Infrastructure, and WanFang Data until September 2017. We calculated pooled hazard ratios (HRs) and 95% CI of miR-17-5 p for overall survival and disease-free survival.

RESULTS

In the categorical variable analysis, we identified 11 studies with 1,279 patients. The pooled analyses suggested that overexpression of miR-17-5 p may predict poor overall survival (HR = 1.86, 95% CI: 1.55-2.25, P<0.001) and disease-free survival (HR = 1.43, 95% CI: 1.01-2.03, P=0.046) in patients with gastrointestinal tumors. Subgroup analysis showed the pooled HR of overall survival was more significant in tissue specimen, Asian patients, and digestive tract tumors. But there was no correlation between the outcomes and European patients.

CONCLUSIONS

This meta-analysis suggested that miR-17-5 p has predictive effects on overall survival and disease-free survival of patients with gastrointestinal tumors.

Quantifying the prognostic significance of microRNA-17/17-5P in cancers: a meta-analysis based on published studies

Objective

The aim of this study was to investigate the prognostic value of mircoRNA-17 and mircoRNA-17-5P (miR-17/17-5P) in patients with cancer.

Materials and methods

We conducted a comprehensive search on published literature following the guidelines of the meta-analysis of observational studies in epidemiology group for design, implementation, and reporting. The methodological qualities for included studies were assessed using the quality in prognosis studies. The pooled hazard ratios (HRs) with 95% CIs for overall survival (OS) and progression-free survival/recurrence-free survival/disease-free survival (PFS/RFS/DFS) were calculated to appraise the associations between miR-17/17-5P expression and cancer prognosis.

Results

A total of 21 studies involving 2099 subjects were analyzed in evidence synthesis. The results showed that high expression of miR-17 was associated with poor OS (HR=2.14; 95% CI: 1.69-2.71, P<0.001) in patients with cancer, especially in Caucasian (HR=2.23; 95% CI: 1.58-3.14, P<0.001) and digestive tract cancer (HR=1.29, 95% CI: 1.03-1.63, P=0.03), and miR-17 expression was significantly correlated with PFS/RFS in cancer patients (HR=1.69, 95% CI: 1.29-2.22, P<0.001). miR-17-5P overexpression was significantly linked with poor OS in cancer patients (HR=1.66; 95% CI: 1.31-2.09, P=0.00), especially in Asian (HR=1.81; 95% CI: 1.37-2.40, P<0.001), digestive tract cancer (HR=1.80; 95% CI: 1.29-2.50, P<0.001), and serum sample (HR=1.76; 95% CI: 1.29-2.41, P<0.001). miR-17-5P expression was significantly associated with DFS in cancer patients (HR=1.58, 95% CI: 1.07-2.35, P=0.02).

Conclusion

High expression of miR-17 and miR-17-5P are significantly associated with poor survival in patients with cancer. This indicated that miR-17/17-5P may be a novel prognostic indicator in cancer.

The role of plasma miRNAs in the diagnosis of pulmonary nodules

Background

In this study, we aimed to assess the clinical utility of detection of plasma microRNAs (miRNAs) in the diagnosis of pulmonary nodules.

Methods

Fifty-seven patients with pulmonary nodules who had undergone surgery were enrolled in our study from July 2016 to July 2017 at Sun Yat-sen University Cancer Center. We measured the expression levels of 12 miRNAs (miRNA-17, -146a, -200b, -182, -155, -221, -205, -126, -7, -21, -145, and miRNA-210) in plasma samples of 57 patients, including 15 benign pulmonary nodules patients and 42 malignant pulmonary nodules patients. The levels of these miRNAs were detected by Real-time quantitative polymerase chain reaction (RT-PCR). The receiver operating characteristic (ROC) curve was used to assess the diagnostic performance of plasma miRNAs for non-small cell lung cancer (NSCLC).

Results

The expression levels of plasma miRNA-17, -146a, -200b, -182, -155, -221, -205, -126, -7, -21, -145, and miRNA-210 are not associated with gender, age, pTNM stage, differentiation grade. The levels of miRNA-17, -146a, -200b, -182, -221, -205, -7, -21, -145, and miRNA-210 in NSCLC patients are significantly higher than those in benign pulmonary nodules patients (P<0.05). However, there are no significant differences for the expression levels of miRNA-155 and miRNA-126. For diagnosing NSCLC, the sensitivity and specificity was 66.7% and 80.0% for miRNA-17, 54.8% and 86.7% for miRNA-146a, 64.3% and 86.7% for miRNA-200b, 83.3% and 73.3% for miRNA-182, 54.8% and 80.0% for miRNA-221, 73.8% and 80.0% for miRNA-205, 78.6% and 73.3% for miRNA-7, 78.6% and 60.0% for miRNA-21, 78.6% and 73.3% for miRNA-145, 76.2% and 73.3% for miRNA-210.

Conclusions

Plasma miRNAs (miRNA-17, -146a, -200b, -182, -221, -205, -7, -21, -145, and miRNA-210) have relatively high sensitivity and specificity for the diagnosis of NSCLC. These plasma miRNAs may be the potential biomarkers for early diagnosis of lung cancer.

Prognostic value of miR-17-5p in cancers: a meta-analysis

Background

Studies have shown that miR-17-5p plays an important role in the development of cancer. The aim of this meta-analysis was to quantitatively analyze the association of miR-17-5p with prognosis in various cancers.

Materials and methods

We searched the PubMed, EMBASE, Web of Science, and Cochrane library databases for relevant studies through August 2017. The prognostic data and clinico-pathological features of overall survival (OS) and disease-free survival (DFS) were extracted to investigate the association between miR-17-5p expression and tumor prognosis. In addition, odds ratios (ORs) were used to assess the correlations between miR-17-5p expression and clinicopathological characteristics.

Results

A total of ten studies were incorporated into this systematic review, and we found that high miR-17-5p expression can predict poor OS for malignancies (combined hazard ratio [HR]=1.87; 95% confidence interval [CI], 1.37–2.55; P=0.000) as well as poor DFS (combined HR=1.60; 95% CI, 1.05–2.44; P=0.027). Further subgroup analyses suggested that high miR-17-5p expression was related to poor OS in Asian patients (combined HR=1.92; 95% CI, 1.37–2.71; P=0.000) and the serum/plasma sample source subgroup (combined HR=2.13; 95% CI, 1.36–3.31; P=0.001). The combined OR indicated that the expression of miR-17-5p was associated with lymph node invasion (OR=1.28; 95% CI, 1.05–1.56; P=0.016) and venous invasion (OR=1.92; 95% CI, 1.40–2.63; P=0.000).

Conclusion

Elevated expression of miR-17-5p suggested a poor prognosis in cancer patients and may serve as a new tumor marker to monitor cancer development and progression.

MicroRNA-17 and the prognosis of human carcinomas: a systematic review and meta-analysis

OBJECTIVE

Although the role of microRNA-17 (miR-17) has been identified as a tumour biomarker in various studies, its prognostic value in cancers remains unclear. Therefore, we performed a systematic review and meta-analysis to analyse and summarise the relationship between the miR-17 status and clinical outcome in a variety of human cancers.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, Web of Science and Embase from the first year of records to 15 May 2017.

OUTCOMES

The patients' survival results were pooled, and pooled HRs with 95% CIs were calculated and used for measuring the strength of association between miR-17 and the prognosis of cancers, including hepatocellular carcinoma, lung cancer, osteosarcoma, glioma, T-cell lymphoblastic lymphoma and colon cancer. Heterogeneity, publication bias and subgroup analysis were also conducted.

RESULTS

A total of 1096 patients were included in this meta-analysis from 12 articles. The results indicated that the increased expression of miR-17 played an unfavourable role in overall survival in various human carcinomas with the HR of 1.342 taking into account the publication bias. In subgroup analysis, HR of ethnicity (non-Asian HR=1.48 and Asian HR=1.40), disease (digestive system HR=1.36 and blood system cancer (HR=2.38) were significant with P<0.05. For the analysis of disease-free survival and recurrence-free survival, the increased expression of miR-17 was associated with unfavourable prognosis (HR=1.40).

CONCLUSIONS

miR-17 may be a useful biomarker in predicting the clinical outcome of human cancers, but due to the limitations of the current studies, further verification of the role of miR-17 in human malignancies is urgently needed.

PROSPERO REGISTRATION NUMBER

CRD42017065749.

MicroRNAs as Novel Biomarkers of Deployment Status and Exposure to Polychlorinated Dibenzo-p-Dioxins/Dibenzofurans

OBJECTIVE

To determine if service members deployed to locations with open air burn pits have different serum microRNA (miRNA) profiles after deployment compared with length-of-service matched, non-deployed individuals. We also tested for correlations between miRNA and serum levels of Polychlorinated Dibenzo-p-Dioxins/Dibenzofurans (PCDD/PCDFs).

METHODS

MiRNAs were isolated and quantified by PCR array. Groups were analyzed for differences in miRNA expression. Correlations between serum miRNA and PCDD/PCDFs were assessed with a linear regression model.

RESULTS

Several miRNAs were differentially expressed after deployment and a partially overlapping set of miRNAs were identified between deployed and non-deployed individuals. Significant correlations between miRNAs and PCDD/PCDFs were identified.

CONCLUSIONS

Serum miRNA levels show a link between deployment to locations with open burn pits and environmental exposures that can take place during deployment.

IRE1α inhibition decreased TXNIP/NLRP3 inflammasome activation through miR-17-5p after neonatal hypoxic-ischemic brain injury in rats

Background

The endoplasmic reticulum (ER) is responsible for the control of correct protein folding and protein function which is crucial for cell survival. However, under pathological conditions, such as hypoxia–ischemia (HI), there is an accumulation of unfolded proteins thereby triggering the unfolded protein response (UPR) and causing ER stress which is associated with activation of several stress sensor signaling pathways, one of them being the inositol requiring enzyme-1 alpha (IRE1α) signaling pathway. The UPR is regarded as a potential contributor to neuronal cell death and inflammation after HI. In the present study, we sought to investigate whether microRNA-17 (miR-17), a potential IRE1α ribonuclease (RNase) substrate, arbitrates downregulation of thioredoxin-interacting protein (TXNIP) and consequent NLRP3 inflammasome activation in the immature brain after HI injury and whether inhibition of IRE1α may attenuate inflammation via miR-17/TXNIP regulation.

Methods

Postnatal day 10 rat pups (n = 287) were subjected to unilateral carotid artery ligation followed by 2.5 h of hypoxia (8% O₂). STF-083010, an IRE1α RNase inhibitor, was intranasally delivered at 1 h post-HI or followed by an additional one administration per day for 2 days. MiR-17-5p mimic or anti-miR-17-5p inhibitor was injected intracerebroventricularly at 48 h before HI. Infarct volume and body weight were used to evaluate the short-term effects while brain weight, gross and microscopic brain tissue morphologies, and neurobehavioral tests were conducted for the long-term evaluation. Western blots, immunofluorescence staining, reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR), and co-immunoprecipitation (Co-IP) were used for mechanism studies.

Results

Endogenous phosphorylated IRE1α expression was significantly increased after HI. Intranasal administration of STF-083010 alleviated brain injury and improved neurological behavior. MiR-17-5p expression was reduced after HI, and this decrease was attenuated by STF-083010 treatment. MiR-17-5p mimic administration ameliorated TXNIP expression, NLRP3 inflammasome activation, caspase-1 cleavage, and IL-1β production, as well as brain infarct volume. Conversely, anti-miR-17-5p inhibitor reversed IRE1α inhibition-induced decrease in TXNIP expression and inflammasome activation, as well as exacerbated brain injury after HI.

Conclusions

IRE1a-induced UPR pathway may contribute to inflammatory activation and brain injury following neonatal HI. IRE1a activation, through decay of miR-17-5p, elevated TXNIP expression to activate NLRP3 inflammasome and aggravated brain damage.

Electronic supplementary material

The online version of this article (10.1186/s12974-018-1077-9) contains supplementary material, which is available to authorized users.

Alteration in microRNA-17-92 dynamics accounts for differential nature of cellular proliferation

MicroRNAs associated with the mir-17-92 cluster are crucial regulators of the mammalian cell cycle, as they inhibit transcription factors related to the E2F family that tightly control decision-making events for a cell to commit for active cellular proliferation. Intriguingly, in many solid cancers, these mir-17-92 cluster members are overexpressed, whereas in some hematopoietic cancers they are down-regulated. Our proposed model of the Myc/E2F/mir-17-92 network demonstrates that the differential expression pattern of mir-17-92 in different cell types can be conceived due to having a contrasting E2F dynamics induced by mir-17-92. The model predicts that by explicitly altering the mir-17-92-related part of the network, experimentally it is possible to control cellular proliferation in a cell type-dependent manner for therapeutic intervention.

Biology of MiR-17-92 Cluster and Its Progress in Lung Cancer

MicroRNAs, a class of short endogenous RNAs, acting as post-transcriptional regulators of gene expression, mostly silence gene expression via binding imperfectly matched sequences in the 3'UTR of target mRNA. MiR-17-92, a highly conserved gene cluster, has 6 members including miR-17, miR-18a, miR-19a, miR-20a, miR-19b-1 and miR-92a. The miR-17-92 cluster, regarded as oncogene, is overexpressed in human cancers. Lung cancer is the leading cause of death all over the world. The molecular mechanism of lung cancer has been partly known at the levels of genes and proteins in last decade. However, new prognosis biomarkers and more target drugs should be developed in future. Therefore, noncoding RNAs, especially miRNAs, make them as new potentially clinical biomarkers for diagnosis and prognosis. In this review, we focus the current progress of miR-17-92 cluster in lung cancer.

Paraquat and MPTP alter microRNA expression profiles, and downregulated expression of miR-17-5p contributes to PQ-induced dopaminergic neurodegeneration

Recent evidence indicates that microRNAs (miRNAs) play a key role in neurodegenerative diseases. However, the toxic effects of paraquat (PQ) and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) on miRNA expression profiles in dopaminergic neurons have not been investigated. In the present study, we used microarray analysis to show that PQ and MPTP induce alterations of miRNA expression in neuro-2a cells. The results reveal that treatment with 300 μm PQ caused miRNA deregulation, such that 60 miRNAs were upregulated and 228 miRNAs were downregulated. Following treatment with 300 μm MPTP, a total of 576 miRNAs were dysregulated, of which 506 were upregulated and 70 were downregulated. Alterations in the expression of miR-17-5p, miR-210-3p, miR-374-5p, miR-378-3p and miR-503-5p were verified by real-time quantitative reverse transcriptase polymerase chain reaction. Moreover, overexpression of miR-17-5p in Neuro-2a cells enhanced cell proliferation, suppressed apoptosis and promoted S phase transition of the cell cycle after PQ treatment. Taken together, our study demonstrates that characteristic changes in miRNA expression profiles occur after PQ and MPTP treatment, which suggests that miRNAs may be involved in the development of PQ- and MPTP-induced neurodegeneration. Downregulated miR-17-5p expression contributes to PQ-induced dopaminergic neurodegeneration.

Downregulation of miR-221-3p and upregulation of its target gene PARP1 are prognostic biomarkers for triple negative breast cancer patients and associated with poor prognosis

The purpose of this study was to identify microRNAs (miRNAs) closely associated with the prognosis of triple-negative breast cancer (TNBC) and their possible targets. This study recruited 125 early-stage TNBC patients, including 40 cases in the experimental group (20 cases with poor prognoses vs. 20 cases with good prognoses) and 85 cases in the validation group (27 cases with poor prognoses vs. 58 cases with good prognoses). In the experimental group, miRNA microarray showed 34 differentially expressed miRNAs in patients with different prognoses. We selected 5 miRNAs for validation. The differential expression of miR-221-3p was further verified in the experimental and validation groups using real-time polymerase chain reaction (PCR). High miR-221-3p expression was associated with better 5-year disease-free survival (DFS) (HR = 0.480; 95% CI, 0.263-0.879; p = 0.017) of TNBC patients. High expression of its target gene PARP1 predicted poorer 5-year DFS (HR = 2.236, 95% CI, 1.209-4.136, p = 0.010). MiR-221-3p down-regulated PARP1 by targeting its 3'-untranslated region. In conclusion, low miR-221-3p expression may contribute to the poor outcome of TNBC patients through regulating PARP1. MiR-221-3p likely plays a role as a PARP1 inhibitor by directly regulating PARP1 expression, thereby affecting the prognoses of TNBC patients.

Prognostic value of high-expression of miR-17-92 cluster in various tumors: evidence from a meta-analysis

The prognostic value of miR-17-92 cluster high-expression in various tumors remains controversial. Therefore, we conducted this meta-analysis by searching literatures in PubMed, Embase, Cochrane Library, China Biology Medicine disc, China National Knowledge Infrastructure to identify eligible studies. Eventually, we analyzed 36 articles that examined 17 tumor types from 4965 patients. Consequently, high-expression of miR-17-92 cluster in various tumors was associated with unfavorable overall survival in both univariate (HR = 2.05, 95%CI: 1.58-2.65, P<0.001) and multivariate (HR = 2.14, 95%CI: 1.75-2.61, P<0.001) analyses. Likewise, similar results were found in different subgroups of country, test method, miR-17-92 cluster component, sample source and size. Additionally, high-expression of miR-17-92 cluster was linked with poor disease-free survival (Univariate: HR = 1.96, 95%CI: 1.55-2.48, P<0.001; Multivariate: HR = 2.18, 95%CI: 1.63-2.91, P<0.001), favorable progression-free survival (Univariate: HR = 0.36, 95%CI: 0.16-0.80, P = 0.012; Multivariate: HR = 1.55, 95%CI: 0.79-3.05, P = 0.201) and poor cancer specific survival in univariate rather than multivariate analyses (Univariate: HR = 1.77, 95%CI: 1.21-2.60, P = 0.004; Multivariate: HR = 1.77, 95%CI: 0.80-3.92, P = 0.160). However, no association of miR-17-92 cluster high-expression was detected with recurrence or relapse-free survival. In summary, this meta-analysis towards high-expression of miR-17-92 cluster has indicated poor prognosis of various cancers. Notably, future studies comprising large cohort size from multicenter are required to confirm our conclusions.

OncomiR-17-5p: alarm signal in cancer?

Soon after microRNAs entered the stage as novel regulators of gene expression, they were found to regulate -and to be regulated by- the development, progression and aggressiveness of virtually all human types of cancer. Therefore, miRNAs in general harbor a huge potential as diagnostic and prognostic markers as well as potential therapeutic targets in cancer. The miR-17-92 cluster was found to be overexpressed in many human cancers and to promote unrestrained cell growth, and has therefore been termed onco-miR-1. In addition, its expression is often dysregulated in many other diseases. MiR-17-5p, its most prominent member, is an essential regulator of fundamental cellular processes like proliferation, autophagy and apoptosis, and its deficiency is neonatally lethal in the mouse. Many cancer types are associated with elevated miR-17-5p expression, and the degree of overexpression might correlate with cancer aggressiveness and responsiveness to chemotherapeutics - suggesting miR-17-5p to be an alarm signal. Liver, gastric or colorectal cancers are examples where miR-17-5p has been observed exclusively as an oncogene, while, in other cancer types, like breast, prostate and lung cancer, the role of miR-17-5p is not as clear-cut, and it might also act as tumor-suppressor. However, in all cancer types studied so far, miR-17-5p has been found at elevated levels in the circulation. In this review, we therefore recapitulate the current state of knowledge about miR-17-5p in the context of cancer, and suggest that elevated miR-17-5p levels in the plasma might be a sensitive and early alarm signal for cancer ('alarmiR'), albeit not a specific alarm for a specific type of tumor.

Prognostic role of miR-17-92 family in human cancers: evaluation of multiple prognostic outcomes

Recent evidence indicates that miR-17–92 family might be an essential prognostic biomarker for human cancers. However, results are still inconsistent. We therefore performed a meta-analysis to evaluate the predictive role of miR-17–92 family in human cancer prognosis. We searched literatures published before March 31th, 2017 inPubMed, Cochrane and Embase databases. Twenty six studies were included in our analyses. The overall hazard ratios (HRs) showed that high expression level of miR-17-92 family was a predictor of poor overall survival (OS): adjusted HRs = 1.71, 95% confidence intervals (CIs): 1.39–2.11, p < 0.00001, and poor disease-free survival (DFS): adjusted HRs = 2.29, 95% CIs: 1.41–3.72, p = 0.0008. However, no association between miR-17-92 family expression and cancer progress-free survival (PFS) was found (p > 0.05). Subgroup analyses showed that high expression of miR-17-92 family was associated with poor OS (adjusted HRs = 1.89, 95% CIs: 1.43–2.49, p < 0.00001) and DFS (adjusted HRs = 2.83, 95% CIs: 1.59–5.04, p = 0.0003) among the Asian, and no association was found for the Caucasian (p > 0.05). Besides, the HRs of miR-17-92 family high expression in tissue and serum samples was 1.68 (1.35–2.09) and 2.20 (1.08–4.46) for OS, and 1.73 (0.80–3.74) and 3.37 (2.25–5.02) for DFS. It also found that high expression of miR-17-92 family predicted a poor OS in breast cancer, esophageal squamous cell carcinoma, lymphoma and other cancers. Findings suggest that miR-17-92 family can be an effective predictor for prognosis prediction in cancer patients.

MicroRNA-17-5p inhibits proliferation and triggers apoptosis in non-small cell lung cancer by targeting transforming growth factor β receptor 2

MicroRNAs (miRs) are small non-coding RNAs that suppress gene expression by directly binding to the 3′-untranslated region of their target mRNAs. Specific miRs serve key roles in the development and progression of non-small cell lung cancer (NSCLC). The aim of the present study was to determine the mechanism of miR-17-5p in the regulation of NSCLC cell survival and proliferation. Reverse transcription-quantitative polymerase chain reaction data indicated that miR-17-5p was significantly downregulated in 28 NSCLC tissues compared with 7 non-tumorous lung tissues. Furthermore, lower miR-17-5p expression was associated with a higher pathological stage in NSCLC patients. Lower miR-17-5p expression was also observed in several common NSCLC cell lines, including SK-MES-1, A549, SPCA-1, H460, H1229 and HCC827, compared with the bronchial epithelium cell line, BEAS-2B. Additionally, overexpression of miR-17-5p significantly inhibited proliferation while inducing the apoptosis of NSCLC H460 cells. Subsequently, transforming growth factor β receptor 2 (TGFβR2) was identified as a direct target of miR-17-5p using a luciferase reporter assay. Western blot analysis confirmed that miR-17-5p negatively mediated the expression of TGFβR2 in NSCLC cells. Furthermore, small interfering RNA-induced downregulation of TGFβR2 also suppressed the proliferation of H460 cells while triggering apoptosis. Therefore, the results of the current study suggest that miR-17-5p may inhibit proliferation and trigger apoptosis in NSCLC H460 cells at least partially by targeting TGFβR2.

MiR-17-5p promotes cancer cell proliferation and tumorigenesis in nasopharyngeal carcinoma by targeting p21

MicroRNAs (miRNAs) may act as either tumor suppressors or oncogenes in various types of cancers. Previous studies have indicated that miR‐17‐5p is involved in the initiation and development of human tumors. However, its mechanism and function in nasopharyngeal carcinoma (NPC) remain largely unclear. In this study, we evaluated the expression profiles of miR‐17‐5p and p21 in NPC cell lines and tissues by quantitative real‐time PCR (qRT‐PCR). For the analysis, we have established a stable overexpression or depletion of miR‐17‐5p NPC cell lines for analyzing the effects of cell proliferation by MTT, colony formation, and cell cycle assay. A nude mice xenograft model was used to verify the tumor growth in vivo. MiR‐17‐5p was overexpressed, whereas the expression of p21 was downregulated in NPC cell lines and tissues. The miR‐17‐5p expression level was inversely correlated with the p21 mRNA level in NPC samples. Furthermore, analysis of 2^−ΔΔCt value in 81 NPC patients suggested that the elevated expression level of miR‐17‐5p or the downregulated expression level of p21 was significantly correlated with tumor size (T classification) and tumor stage, and Kaplan–Meier survival analysis revealed a correlation between miR‐17‐5p or p21 expression level and overall survival times in 81 NPC patients. MiR‐17‐5p promoted cell growth in vivo and in vitro by directly targeting p21. Our results indicate that miR‐17‐5p can promote the occurrence of NPC and it may serve as a potential novel diagnostic maker or therapeutic target for NPC in the future.