AIMS: The acquired drug resistance has been regarded as a main barrier for the effective treatment of temozolomide (TMZ) in glioblastoma (GBM). MiR-126-3p is commonly down-regulated and exerts tumor-suppressive roles in kinds of human cancers, including GBM. This study was designed to investigate the functions and mechanisms of miR-126-3p in regulating TMZ resistance in GBM.
MATERIALS AND METHODS: qRT-PCR analysis was used to measure the expressions of miR-126-3p and SOX2 mRNA in GBM tissues and cells. Cell viability, colony forming ability and apoptosis were detected to evaluate the effect of miR-126-3p or SOX2 on TMZ resistance. Luciferase reporter experiments were applied to identify the target genes of miR-126-3p. Western blot analysis was performed to determine the protein levels associated with Wnt/β-catenin signaling. TOP/FOP Flash assays were conducted to determine the effects of miR-126-3p or SOX2 on Wnt/β-catenin signaling.
KEY FINDINGS: miR-126-3p expression was decreased in TMZ-resistant GBM tissues and cells. High levels of miR-126-3p enhanced TMZ sensitivity by inhibiting cell viability, reducing colony forming potential and inducing apoptosis. Additionally, SOX2 was identified as a downstream target of miR-126-3p. On the contrary, SOX2 overexpression conferred TMZ resistance of GBM cells. Moreover, miR-126-3p-mediated TMZ sensitivity was reversed following increased expression of SOX2. Furthermore, miR-126-3p-induced inactivation of Wnt/β-catenin signaling was greatly abrogated by SOX2 up-regulation.
SIGNIFICANCE: MiR-126-3p sensitizes GBM cells to TMZ possibly by repressing SOX2 expression and blocking Wnt/β-catenin signaling. This study provides novel targets to overcome TMZ resistance in GBM chemotherapy.

OBJECTIVE: Malignant mesothelioma is an aggressive cancer of the serous membranes. For the detection of the tumor at early stages non- or minimally-invasive biomarkers are needed. The circulating biomarkers miR-132-3p, miR-126-3p, and miR-103a-3p were analyzed in a nested case-control study using plasma samples from 17 prediagnostic mesothelioma cases and 34 matched asbestos-exposed controls without a malignant disease.
RESULTS: Using prediagnostic plasma samples collected in median 8.9 months prior the clinical diagnosis miR-132-3p, miR-126-3p, and miR-103a-3p revealed 0% sensitivity on a defined specificity of 98%. Thus, the analyzed miRNAs failed to detect the cancer in prediagnostic samples, showing that they are not feasible for the early detection of malignant mesothelioma. However, the miRNAs might still serve as possible markers for prognosis and response to therapy, but this needs to be analyzed in appropriate studies.

Background: Breast cancer is most serious reasons of women death around worldwide result in increasing its morbidity and mortality. MicroRNAs are considered as significant regulators of cancer biological processes. The main aim of this study is restoration of miR-126 could lead to modulate breast cell line and impairs their proliferation by targeting vascular endothelial growth factor gene (VEGF-A). Methods: Breast cancer cell line (MCF7) was transfected by miR-126 lipofectamine and negative miR control for 24 hr. Cytotoxic effects of miR-126 lipofectamine were determined by cell viability assay. Cell proliferation and cell cycle were quantitatively measured using PicoGreen assay and DAPI stain-flow cytometer analysis. For further investigation, Taq-Man real time PCR assay was performed to detect relative VEGF-A and miRNA-126 level. Results: MiR-126 was overexpressed in treated breast cancer cell (MCF7) compared with control cells. miR-126 expression has been associated –with a decrease in cell proliferation and arrested MCF7 cells at G1 phase. The study found that vascular endothelial growth factor is regulated by miR- 126. Hence, VEGF-A is considered as functional vital and direct target to miR-126 in breast cancer cell line (MCF7). Conclusions: This study provided that manipulated miR-126 level may suggest a novel therapeutic approach in breast cancer treatment. However, an animal models study is needed to address and prove predictive ability of miR-126 on breast cancer controlling.

Lung cancer is the leading cause of cancer-related death worldwide. Lung adenocarcinoma (AC) cases account for approximately 40% of lung cancers. Early diagnosis can reduce mortality, improve prognosis, prolong survival, and improve quality of life. Specific and stable biomarkers for early diagnosis of AC are still lacking. Exosomal miRNAs are enriched in the circulatory system and are remarkably stable compared to extracellular miRNAs because exosomes protect them from RNase degradation. In our study, we isolated serum exosomal miRNAs from AC patients and from healthy controls to find highly stable and sensitive biomarkers for early detection of AC. 23 AC patients and 16 healthy controls were included in this study. After microRNA (miR) extraction from serum exosomes (ex-miR), the expression of ex-miRs in cases and controls was quantified by quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR). Overexpression of serum ex-miR-21-5p, -126-3p, and -140-5p was observed in AC patients. Area under the curve values for selected candidate ex-miRs were 0.97(95% confidence interval [CI], 0.846-0.99) for ex-miR-21-5p, 0.91(95% CI, 0.77-0.98) for ex-miR-126-3p, and 0.88 (95% CI, 0.73-0.97) for ex-miR-140-5p. Conclusion: Serums ex-miR-21-5p, -126-3p, and -140-5p have great potential to serve as highly sensitive, stable, and repeatable biomarkers for early diagnosis of AC. However, larger cohort studies are necessary to validate these results.

Recent studies identified that low levels of tumour suppressor microRNAs (miRNAs) in plasma/serum relate to tumour progression and poor outcomes in cancers. We selected six candidates (miR-126, 133b, 143, 203, 338-3p, 655) of tumour suppressor miRNAs in oesophageal squamous cell carcinoma (ESCC) by a systematic review of NCBI database. Of these, miR-655 levels were significantly down-regulated in plasma of ESCC patients compared to healthy volunteers by test- and validation-scale analyses. Low levels of plasma miR-655 were significantly associated with lymphatic invasion, lymph node metastasis and advanced stage. Univariate and multivariate analysis revealed that the low level of plasma miR-655 was an independent risk factor of lymphatic progression and a poor prognostic factor. Overexpression of miR-655 in ESCC cells inhibited cell proliferation, migration, invasion and epithelial-mesenchymal transition. Increased plasma miR-655 levels by the subcutaneous injection significantly inhibited lymph node metastasis in mice. Low levels of miR-655 in plasma relate to lymphatic progression and poor outcomes, and the restoration of the plasma miR-655 levels might inhibit tumour and lymphatic progression in ESCC.

OBJECTIVE: Long non-coding RNA-ATB (Lnc-ATB) have been reported to promote tumor proliferation and metastasis via regulation of tumor suppressive miRNA-related signals. Patients with endometrial cancer (EC) have advanced stage disease or metastasis have poor prognosis. We here investigated the role of Lnc-ATB in endometrial cancer.
METHODS: Endometrial cancer tissues and normal tissues (n = 35) were collected to determine the expression and clinical significance of Lnc-ATB, and bioinformatics analysis was used to predict the miRNA target. siRNA was used to estimate the function of Lnc-ATB in EC cell lines and in vivo.
RESULT: The expression of Lnc-ATB is up-regulated in tumor tissues and EC cell lines. Patients with high expressed Lnc-ATB have high FIGO stage and poor tumor differentiation. The tumor suppressor miR-126 interacted with Lnc-ATB. Down-regulated miR-126 negative correlated with FIGO stage and tumor differentiation. Knockdown of Lnc-ATB in RL95 and HEC1A cell lines increased the miR-126 level and impaired the cell vitality, induced caspase-3-related tumor apoptosis and G1/S arrest. However, abrogation of miR-126 by its inhibitors counteracted Lnc-ATB knockdown-induced tumor inhibition via regulation of miR-126 target gene PIK3R2 and Sox2-related apoptosis and cell cycle pathway. Meanwhile, Lnc-ATB knockdown also suppressed the migration and invasion and inhibited TGF-β-induced epithelial-mesenchymal transition (EMT) phenotype via miR-126. Knockdown of Lnc-ATB in vivo remarkably induced tumor regression via restoration of tumor suppressor miR-126, leading to deceased tumor volume, reduced expression of PCNA and PIK3R2/Sox2 signals and EMT phenotype in tumor tissues.
CONCLUSION: These data demonstrate the tumorigenic role of Lnc-ATBs in endometrial cancer via abrogation of tumor suppressor miR-126 signals.

Lung adenocarcinoma (LUAD) is the most common histological subtype of lung cancer. Previous studies have found that many microRNAs (miRNAs), including miRNA‑126‑3p, may play a critical role in the development of LUAD. However, no study of LUAD has researched the synergistic effects and co‑targets of both miRNA‑126‑3p and miRNA‑126‑5p. The present study used real‑time quantitative polymerase chain reaction (RT‑qPCR) to explore the expression values of miRNA‑126‑3p and miRNA‑126‑5p in 101 LUAD and 101 normal lung tissues. Ten relevant microarray datasets were screened to further validate the expression levels of miRNA‑126‑3p and ‑5p in LUAD. Twelve prediction tools were employed to obtain potential targets of miRNA‑126‑3p and miRNA‑126‑5p. The results showed that both miRNA‑126‑3p and ‑5p were expressed significantly lower in LUAD. A significant positive correlation was also present between miRNA‑126‑3p and ‑5p expression in LUAD. In addition, lower expression of miRNA‑126‑3p and ‑5p was indicative of vascular invasion, lymph node metastasis (LNM), and a later tumor/node/metastasis (TNM) stage of LUAD. The authors obtained 167 targets of miRNA‑126‑3p and 212 targets of miRNA‑126‑5p; 44 targets were co‑targets of both. Eight co‑target genes (IGF2BP1, TRPM8, DUSP4, SOX11, PLOD2, LIN28A, LIN28B and SLC7A11) were initially identified as key genes in LUAD. The results of the present study indicated that the co‑regulation of miRNA‑126‑3p and miRNA‑126‑5p plays a key role in the development of LUAD, which also suggests a fail‑proof mode between miRNA‑3p and miRNA‑126‑5p.

Yes-associated protein 1 (YAP1) exerts significant effects in various malignancies. However, the oncogenic role of YAP1 remains controversial, and the mechanism by which YAP1 regulates non-coding RNAs is still largely unknown. The present study aimed to assess the effect of YAP1 on the malignant behaviors of colorectal carcinoma (CRC) and explore the underlying regulatory mechanism of the YAP1-MALAT1-miR-126-5p axis. YAP1 was highly expressed in CRC tissues as assessed by GSE20916 and its expression was negatively correlated with overall survival in 83 CRC cases. Meanwhile, YAP1 promoted proliferation, invasion, and migration in colon cancer cells, in vitro and in vivo. MALAT1 was obviously expressed, with differential expression of 11 lncRNAs in HCT116 cells after transfection with siYAP1 or si-Ctl. Based on bioinformatics prediction, immunoprecipitation (IP), and chromatin immunoprecipitation (ChIP), the interaction of YAP1 with TCF4/β-catenin was regulated by MALAT1. Bioinformatics prediction, dual luciferase assay, RNA-IP, and RNA pull-down assay demonstrated that YAP1-induced MALAT1 promoted the expression of metastasis-associated molecules such as VEGFA, SLUG, and TWIST, by sponging miR-126-5p in CRC. These findings indicated that the YAP1-MALAT1-miR-126-5p axis could control angiogenesis and epithelial-mesenchymal transition in CRC, providing potential biomarkers and therapeutic targets for CRC.

Endothelial cell (EC) plasticity in pathological settings has recently been recognized as a driver of disease progression. Endothelial-to-mesenchymal transition (EndMT), in which ECs acquire mesenchymal properties, has been described for a wide range of pathologies, including cancer. However, the mechanism regulating EndMT in the tumor microenvironment and the contribution of EndMT in tumor progression are not fully understood. Here, we found that combined knockdown of two ETS family transcription factors, ERG and FLI1, induces EndMT coupled with dynamic epigenetic changes in ECs. Genome-wide analyses revealed that ERG and FLI1 are critical transcriptional activators for EC-specific genes, among which microRNA-126 partially contributes to blocking the induction of EndMT. Moreover, we demonstrated that ERG and FLI1 expression is downregulated in ECs within tumors by soluble factors enriched in the tumor microenvironment. These data provide new insight into the mechanism of EndMT, functions of ERG and FLI1 in ECs, and EC behavior in pathological conditions.

BACKGROUND: Ovarian cancer is the leading cause of death by gynecologic cancers in the Western world. The aim of the study was to identify microRNAs (miRNAs) associated with prognosis and/or resistance to chemotherapy among patients with epithelial ovarian cancer.
METHODS: Using information from the Pelvic Mass Study we identified a cohort of women with epithelial ovarian cancer. Tumor tissues were then collected and analyzed by global miRNA microarrays. MiRNA profiling was then linked to survival and time to progression using Cox proportional-hazards regression models. Logistic regression models were used for the analysis of resistance to chemotherapy. Our results were validated using external datasets retrieved from the NCBI Gene Expression Omnibus database.
RESULTS: A total of 197 patients with epithelial ovarian cancer were included for miRNA microarray analysis. In multivariate analyses we identified a number of miRNAs significantly correlated with overall survival (miR-1183 (HR: 1.42, 95% CI:1.17-1.74, p = 0.0005), miR-126-3p (HR: 1.38, 95% CI:1.11-1.71, p = 0.0036), time to progression (miR-139-3p (HR: 1.48, 95% CI: 1.13-1.94, p = 0.0047), miR-802 (HR: 0.48, 95% CI: 0.29-0.78, p = 0.0035)), progression free survival (miR-23a-5p (HR:1.32, 95% CI:1.09-1.61, p = 0.004), miR-23a-3p (HR:1.70, 95% CI:1.15-2.51, p = 0.0074), miR-802 (HR: 0.48, 95% CI: 0.29-0.80, p = 0.0048)), and resistance to chemotherapy (miR-1234 (HR: 0.26, 95% CI: 0.11-0.64, p = 0.003)). A few miRNAs identified in our training cohort, were validated in external cohorts with similar results.
CONCLUSION: Eight miRNAs were identified as significant predictors of overall survival, progression free survival, time to progression, and chemotherapy resistance. A number of these miRNAs were significantly validated using external datasets. Inter-platform and inter-laboratory variations may have influence on the ability to compare and reproduce miRNA results. The use of miRNAs as potential markers of relapse and survival in ovarian cancer warrants further investigation.

OBJECTIVE: This study aimed to evaluate predictive value of 14 pro-angiogenic miRNAs for cardiotoxicity induced by epirubicin/cyclophosphamide follow by docetaxel (EC-D) in breast cancer (BC) patients.
METHODS: Three hundred and sixty-three BC patients receiving EC-D neoadjuvant chemotherapy were consecutively enrolled in this prospective cohort study. Peripheral blood sample was obtained from each patient, and plasma was separated. The expressions of 14 pro-angiogenic miRNAs, cardiac troponin I (cTnI) and N-terminal pro brain natriuretic peptide (NT-proBNP) were evaluated. Left ventricular ejection fraction (LVEF) level at C0, the end of 4 cycles of EC chemotherapy (C4), the end of 4 cycles of docetaxel treatment (C8), 3rd months (M3), 6th months (M6), 9th months (M9) and 12th months (M12) after surgery were assessed.
RESULTS: LVEF decreased at C4, C8, M3, M6, M9 and M12 compared with C0, and the total cardiotoxicity incidence was 5.2%. Additionally, the levels of let-7f, miR-17-5p, miR-20a, miR-126, miR-210 and miR-378 were reduced in cardiotoxicity patients. Multivariate logistic regression revealed that miR-17-5p and miR-20a were independently predictive factors for less cardiotoxicity. Receiver operating characteristics (ROC) curve displayed a satisfactory predictive value for lower cardiotoxicity risk with area under curve (AUC) of 0.842 of the combination of the miR-17-5p and miR-20a expressions. In addition, let-7f,miR-126, miR-210 and miR-378 levels negatively correlated with cTnI expression, and let-7f and miR-130a expressions reversely correlated with NT-proBNP level.CONLUSIONS: miR-17-5p and miR-20a could be served as biomarkers for lower cardiotoxicity induced by EC-D neoadjuvant chemotherapy in BC patients.

Colorectal cancer (CRC) is a major cause of death worldwide. Novel non-invasive, high diagnostic value screening test is urgently needed to improve survival rate, treatment and prognosis. Stable, small, circulating microRNA (miRNA) offers unique opportunities for the early diagnosis of several diseases. It acts as tumor oncogenes or suppressors and involve in cell death, survival, and metastasis. Communication between miRNA and carcinogenesis is critical but it still not clear and needs further investigation. The aim of our study is to evaluate the role of miR-210, miR-21, miR-126, as non-invasive diagnostic biomarkers for screening, early detection of CRC, studying their correlation with prognostic variables, and clarifying the roles of miRNAs on HIF-1α-VEGF signaling pathway. The expression of miR-210, miR-21 and miR-126 was performed using qRT-PCR in adenocarcinoma (no = 35), adenomas (no = 51), and neoplasm free controls (no = 101). Serum levels of VEGF and HIF-1α was determined by ELISA Kit. The results show that the expression of miR-210, miR-21, VEGF, HIF-1α was significantly up-regulated while that miRNA-126 was down-regulated in both adenocarcinoma and adenomas compared with controls (p < 0.001 for each). No significant difference was noted comparing patients with adenocarcinoma and adenomas. The three miRNAs correlated with VEGF, HIF-α. The miR-210 and miR-21 associated with TNM classification and clinical staging of adenocarcinoma (p < 0.001) and they show high diagnostic value with sensitivity and specificity 88.6%, 90.1% and 91.4%, 95.0% respectively. Our study revealed that circulating miR-210, miR-21 were up-regulated while miR-126 was down-regulated in CRC and adenomas patients, they all correlated with TNM staging and they had high diagnostic value. HIF-1α VEGF signaling pathways regulated by miRNAs played a role in colon cancer initiation. To the best of our knowledge, this is the first study of this miRNAs panel in CRC in our community. These data suggested that these biomarkers could be a potential novel, non-invasive marker for early diagnosis, screening and predicting prognosis of CRC. Understanding the molecular functions by which miRNAs affect cancer and understanding its roles in modulating the signaling output of VEGF might be fruitful in reducing the incidence and slowing the progression of this dark malignancy.

BACKGROUND Renal cell carcinoma (RCC) is one of the common malignant tumors in the urinary system, which endangers human health for a long time. The past decade, the molecular biology of renal cell carcinoma has made considerable progress, so that we have a more profound understanding of renal cell carcinoma. Molecular biological mechanism of renal cell carcinoma remains to be explored. Evidence indicates that long non-coding RNAs (lncRNAs) may be important players in human cancer progression, including RCC. In this study, we found that a newly discovered pseudogene-derived lncRNA named DUXAP8, a 2107-bp RNA, was remarkably upregulated in RCC. MATERIAL AND METHODS Expression of lncRNA DUXAP8 was determined by a qRT-PCR assay in RCC tissues. The proliferation and invasion of RCC cell were measured by a cell proliferation assay and a Transwell invasion assay. Expression of miR-126 was detected by real-time PCR. Interactions between lncRNA DUXAP8 and miR-126 were measured by a luciferase reporter assay and an RNA-pull down assay. In vivo experiments were used to detect tumor formation. RESULTS Together, our study not only identifies lncRNA DUXAP8 as a negative regulator of renal cancer with potential clinical value, but also reveals a regulatory mechanism by long non-coding RNAs to control tumor development. CONCLUSIONS Results from this study provide evidence that lncRNA DUXAP8 enhances renal cell carcinoma progression via downregulating of miR-126, which offers a new approach for the treatment of RCC.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most lethal cancer, mainly attributing to its high tendency to metastasis. Vascular invasion provides a direct path for solid tumor metastasis. Mounting evidence has demonstrated that microRNAs (miRNAs) are related to human cancer onset and progression including invasion and metastasis.
METHODS: In search of invasion-metastasis-associated miRNAs in HCC, microarray dataset GSE67140 was downloaded from the Gene Expression Omnibus database. Differentially expressed miRNAs (DE-miRNAs) were obtained by R software package and the potential target genes were predicted by miRTarBase. The database for annotation, visualization and integrated discovery (DAVID) was introduced to perform functional annotation and pathway enrichment analysis for these potential targets of DE-miRNAs. Protein-protein interaction (PPI) network was established by STRING database and visualized by Cytoscape software. The effects of the miR-494-3p and miR-126-3p on migration and invasion of HCC cell lines were evaluated by conducting wound healing assay and transwell assay.
RESULTS: A total of 138 DE-miRNAs were screened out, including 57 upregulated miRNAs and 81 downregulated miRNAs in human HCC tumors with vascular invasion compared with human HCC tumors without vascular invasion. 762 target genes of the top three upregulated and downregulated miRNAs were predicted, and they were involved in HCC-related pathways, such as pathway in cancer, focal adhesion and MAPK signaling pathway. In the PPI network, the top 10 hub nodes with higher degrees were identified as hub genes, such as TP53 and MYC. Through constructing the miRNA-hub gene network, we found that most of hub genes could be potentially modulated by miR-494-3p and miR-126-3p. Of note, miR-494-3p and miR-126-3p was markedly upregulated and downregulated in HCC cell lines and tissues, respectively. In addition, overexpression of miR-494-3p could significantly promote HCC migration and invasion whereas overexpression of miR-126-3p exerted an opposite effect.
CONCLUSIONS: Targeting miR-494-3p and miR-126-3p may provide effective and promising approaches to suppress invasion and metastasis of HCC.

BACKGROUND: Few biomarkers are available for the prediction of prognosis and recurrence in lymph node (LN)-negative gastric cancer (GC) currently. miR-126 functions as a tumor suppressor in GC, however, its clinical significance in LN-negative GC remains unknown.
AIM: To investigate the associations of tissue miR-126 level with the clinicopathological characteristics and clinical outcome of LN-negative GC patients.
METHODS: Quantitative real-time polymerase chain reaction was performed to examine the tissue miR-126 level in 315 LN-negative GC patients who underwent curative gastrectomy with D2 lymphadenectomy. The associations of tissue miR-126 level with clinicopathological characteristics and clinical outcome were evaluated.
RESULTS: Compared with matched adjacent non-tumor tissues, miR-126 expression was significantly down-regulated in tumor tissues. A reduced tissue miR-126 level statistically correlated with aggressive clinicopathological characteristics, including larger tumor size, deeper local invasion, and poorer prognosis. Notably, multivariate analysis identified advanced T stage and low miR-126 level as independent predictors of the unfavorable prognosis and recurrence of LN-negative GC.
CONCLUSIONS: These results indicate for the first time that advanced T stage and low miR-126 level are predictors of unfavorable prognosis and recurrence in LN-negative GC patients. These parameters should be taken into account to stratify patients for adjuvant therapy and close follow-up.

BACKGROUND The aim of this study was to assess the utility of miR-126 in promoting malignant glioma progression and determine if miR-126 might be a target for malignant glioma treatment. MATERIAL AND METHODS The expression of miR-126 in malignant glioma tissues and cells was detected by reverse transcription polymerase chain reaction (RT-PCR). Western blot analysis was used to detect changes in protein levels. Transwell assay was applied to assess the migration and invasion in vitro. Luciferase reporter assay was used to confirm the binding of miR-126 and mature T cell proliferation 1 (MTCP1). A nude mouse tumor model was used to assess the molecular mechanism in vivo. RESULTS The expression level of miR-126 in patients with stage III~IV malignant glioma was significant lower than that in patients with stage I~II. In different malignant glioma cell lines, the expression was significantly reduced in U87MG. Compared with the control mimics group, the expression of MTCP1 was significantly decreased. The results of Transwell assay showed that the invasiveness and migration in the miR-126 mimics group was significantly lower than in the control mimics groups. miR-126 mimics did not affect luciferase activity in the Mut-miR-126/MTCP1 group, while miR-126 mimics reduced luciferase activity by 54% in the Wt-miR-126/MTCP1 group. The results of invasion showed that the invasion ability in the miR-126 inhibitor group was significantly increased compared with that in the normal control (NC) group, while the invasion and migration abilities in the MTCP1 siRNA group were significantly increased. After 6 weeks, the tumor volume in the miR-126 inhibitor group was significantly increased, while that in the MTCP1 siRNA group was significantly decreased. CONCLUSIONS miR-126 inhibits the migration of malignant glioma cells by inhibiting MTCP1.

BACKGROUND: Intestinal-type sinonasal adenocarcinomas (ITACs) are aggressive malignancies related to wood dust and leather exposure. ITACs are generally associated with advanced stage at presentation due to the insidious growth pattern and non-specific symptoms. Therefore, biomarkers that can detect the switch from the benign disease to malignancy are needed. Essential for tumour growth, angiogenesis is an important step in tumour development and progression. This process is strictly regulated, and MiR-126 considered its master modulator.
METHODS: We have investigated MiR-126 levels in ITACs and compared them to benign sinonasal lesions, such as sinonasal-inverted papillomas (SIPs) and inflammatory polyps (NIPs). The tumour-suppressive functions of MiR-126 were also evaluated.
RESULTS: We found that MiR-126 can significantly distinguish malignancy from benign nasal forms. The low levels of MiR-126 in ITACs point to its role in tumour progression. In this context, restoration of MiR-126 induced metabolic changes, and inhibited cell growth and the tumorigenic potential of MNSC cells.
CONCLUSIONS: We report that MiR-126 delivered via exosomes from endothelial cells promotes anti-tumour responses. This paracrine transfer of MiRs may represent a new approach towards MiR-based therapy.

In vitro, microRNA-126 (miR-126) inhibits SLK cell proliferation, inhibits the cell cycle, induces cell apoptosis, and reduces cell invasiveness. Double luciferase assays have shown that phosphatidylinositol-3 kinase (PI3K) is the miR-126 target in SLK cells. We aimed to investigate the influence of miR-126 on the phosphate and tension homology deleted on chromosome ten (PTEN)/PI3K/protein kinase B (AKT) pathway members in SLK cells and to determine the expression of these pathway members in Kaposi's sarcoma (KS). The mimic and inhibitor of miR-126 were transfected into SLK cells and PTEN and AKT1 expression was assayed in SLK cells by real-time quantitative PCR and western blotting. PTEN, AKT1, phosphorylated (P)-PTEN, and phosphorylated (P)-AKT expression in KS and paraneoplastic skin were assayed by immunohistochemistry. AKT1 expression was downregulated in SLK cells that overexpressed miR-126, while there was no significant difference in PTEN expression between SLK cells overexpressing miR-126 and those in which its expression was knocked down. PTEN and AKT1 were expressed in KS and paraneoplastic skin but P-AKT was not. Interestingly, P-PTEN was not expressed in paraneoplastic skin but it was expressed in 90% of KS biopsies (P < .05). P-PTEN expression was also significantly higher in visceral than in cutaneous KS (P = .01) and was higher in indoor than in outdoor workers (P = .018). In vitro, miR-126 negatively regulated AKT1 expression but no regulation of PTEN expression was evident. Results indicated that in KS, PTEN is activated and may therefore be a potential therapeutic target for KS. In addition, these results also indicate that sunlight may not be the cause of KS.

BACKGROUND AND OBJECTIVES: MicroRNAs (miRs) are noncoding RNAs that regulate protein translation and melanoma progression. Changes in plasma miR expression following surgical resection of metastatic melanoma are under-investigated. We hypothesize differences in miR expression exist following complete surgical resection of metastatic melanoma.
METHODS: Blood collection pre- and post-surgical resection was performed in six individuals with solitary melanoma metastases. miR expression in extracted RNA was quantified using the NanoString nCounter Digital Analyzer.
RESULTS: Pre- and post-surgical plasma samples contained 216 miRs with expression above baseline. Comparison of postsurgical to preresection samples revealed differential expression of 25 miRs: miR-let-7a, miR-let7g, miR-15a, miR-16, miR-22, miR-30b, miR-126, miR-140, miR-145, miR-148a, miR-150-5p, miR-191, miR-378i, miR-449c, miR-494, miR-513b, miR-548aa, miR-571, miR-587, miR-891b, miR-1260a, miR 1268a, miR-1976, miR-4268, miR-4454 (P < 0.05). Utilizing P < 0.0046 as a cutoff to control for one false positive among the 216 miRs revealed that postsurgical melanoma plasma samples had upregulation of miR-1260a (P = 0.0007) and downregulation of miR-150-5p (P = 0.0026) relative to pre-surgical samples.
CONCLUSIONS: Differential expression of miR-150-5p and miR-1260a is present in plasma following surgical resection of metastatic melanoma in this small sample (n = 6) of melanoma patients. Therefore, further investigation of these plasma miRs as noninvasive biomarkers for melanoma is warranted.

Specific microRNAs (miRNAs) are packaged in exosomes that regulate processes in tumor development and progression. The current study focuses on the influence of exosomal miRNAs in the pathogenesis of epithelial ovarian cancer (EOC). MiRNA profiles were determined in exosomes from plasma of 106 EOC patients, eight ovarian cystadenoma patients, and 29 healthy women by TaqMan real-time PCR-based miRNA array cards containing 48 different miRNAs. In cell culture experiments, the impact of miR-200b and miR-320 was determined on proliferation and apoptosis of ovarian cancer cell lines. We report that miR-21 (P = 0.0001), miR-100 (P = 0.034), miR-200b (P = 0.008), and miR-320 (P = 0.034) are significantly enriched, whereas miR-16 (P = 0.009), miR-93 (P = 0.014), miR-126 (P = 0.012), and miR-223 (P = 0.029) are underrepresented in exosomes from plasma of EOC patients as compared to those of healthy women. The levels of exosomal miR-23a (P = 0.009, 0.008) and miR-92a (P = 009, 0.034) were lower in ovarian cystadenoma patients than in EOC patients and healthy women, respectively. The exosomal levels of miR-200b correlated with the tumor marker CA125 (P = 0.002) and patient overall survival (P = 0.019). MiR-200b influenced cell proliferation (P = 0.0001) and apoptosis (P < 0.008). Our findings reveal specific exosomal miRNA patterns in EOC and ovarian cystadenoma patients, which are indicative of a role of these miRNAs in the pathogenesis of EOC.

Glioblastoma (GBM) is a typically lethal type of brain tumor with a median survival of 15 months postdiagnosis. This negative prognosis prompted the exploration of alternative treatment options. In particular, the reliance of GBM on angiogenesis triggered the development of anti-VEGF (vascular endothelial growth factor) blocking antibodies such as bevacizumab. Although its application in human GBM only increased progression-free periods but did not improve overall survival, physicians and researchers still utilize this treatment option due to the lack of adequate alternatives. In an attempt to improve the efficacy of anti-VEGF treatment, we explored the role of the

Ovarian cancer is one of the leading malignancies in women and the 5-year survival rate of ovarian cancer still remains poor. In the present study, we aimed to investigate the interaction between the miR-126-3p and PLXNB2 in the progression of ovarian cancer. The qRT-PCR data revealed a reduction of miR-126-3p level in ovarian cancer tissues comparing to the adjacent normal tissues. Over-expression of miR-126-3p in ovarian cancer cells suppressed cell proliferation and invasion and the phosphorylation of AKT and ERK1/2. The cell cycle assay results showed that the over-expression of miR-126-3p induced cells in G1-phase and reduced cells in S-phase. We further performed bioinformatics analysis and luciferase assay to investigate the relationship between miR-126-3p and PLXNB2 in ovarian cancer cells. The results of TargetScan suggested that PLXNB2 is a direct target of miR-126-3p in ovarian cancer cells, and luciferase assay confirmed bioinformatics prediction. Knocking down of PLXNB2 with PLXNB2 siRNA results in repressed ovarian cancer cell proliferation and invasion, and decreased phosphorylation of AKT and ERK1/2, which is similar to the effect of over-expression of miR-126-3p in OC cells. The synergistic effect of combination of miR-126-3p over-expression and PLXNB2 down-regulation on the cell growth viability, cell colony, and cell invasion was also identified. All these findings indicated that miR-126-3p is involved in the progression of ovarian cancer via direct regulating PLXNB2.

The detection of peripheral circulating tumor-derived components, such as cell-free microRNAs, circulating microvesicles, and exosomal microRNAs, has been shown as a promising noninvasive strategy. However, the different roles of these components in tumor therapy evaluations have remained largely undefined. In this paper, we employed an in vivo model of the human clear cell renal cell carcinoma line Caki-1-bearing mice to evaluate the therapeutic effects of cryoablation, which is a new minimally invasive treatment for renal cell carcinoma. At different times after cryoablation, we found that the levels of the cell-free microRNAs miR-122, miR-155 and miR-210 were first increased and then decreased. Additionally, the number of large-sized microvesicles was increased after cryoablation, but the number of small-sized circulating microvesicles did not change. Furthermore, the exosomal microRNAs miR-126-3p, miR-17-5p, and miR-21-3p rapidly decreased one day after cryoablation, an effect that was well correlated with the treatment degree. Therefore, we suggest that these circulating components may have different levels of importance in the evaluation of the efficacy of renal cell cryoablation, furthermore, exosomal microRNAs may be more suitable for the early postoperative judgment of tumor elimination effects, which are worth further exploration in clinical practice.

Blood plasma microRNAs (miRNAs) are emerging as a clinically useful tool for non-invasive detection and prognosis estimation in various cancer types including pancreatic ductal adenocarcinoma (PDAC). The aim of the present study was to provide an independent validation of circulating miRNAs identified in previous studies as diagnostic and/or prognostic biomarkers in PDAC. Based on the literature search, 6 miRNAs were chosen as candidates for independent validation; miR-21-5p, miR-375, miR-155, miR-17-5p, miR-126-5p and miR-1290. Validation of these miRNAs was performed in a cohort of 25 patients with PDAC undergoing surgical resection and 24 healthy donors. Plasma levels of miRNAs were determined using quantitative real-time PCR. We confirmed significantly higher levels of all tested miRNA in blood plasma of PDAC patients in comparison to healthy controls with miR-21-5p showing the highest analytical performance (p<0.001; AUC>0.99). Increased levels of miR-21-5p (p=0.045) and miR-375 (p=0.013) were significantly associated with overall survival. Multivariate analysis demonstrated that miR-21-5p is a significant unfavorable prognostic factor independent on other clinical variables including adjuvant chemotherapy (hazard ratio 2.95; 95% CI 1.06-8.18; p=0.038). Our preliminary data indicate promising diagnostic and prognostic utility of plasma miR-21-5p in PDAC patients.

Baculovirus (BV) holds promise as a vector for anticancer gene delivery to combat the most common liver cancer-hepatocellular carcinoma (HCC). However, in vivo BV administration inevitably results in BV entry into non-HCC normal cells, leaky anticancer gene expression and possible toxicity. To improve the safety, we employed synthetic biology to engineer BV for transgene expression regulation. We first uncovered that miR-196a and miR-126 are exclusively expressed in HCC and normal cells, respectively, which allowed us to engineer a sensor based on distinct miRNA expression signature. We next assembled a synthetic switch by coupling the miRNA sensor and RNA binding protein L7Ae for translational repression, and incorporated the entire device into a single BV. The recombinant BV efficiently entered HCC and normal cells and enabled cis-acting transgene expression control, by turning OFF transgene expression in normal cells while switching ON transgene expression in HCC cells. Using pro-apoptotic hBax as the transgene, the switch-based BV selectively killed HCC cells in separate culture and mixed culture of HCC and normal cells. These data demonstrate the potential of synthetic switch-based BV to distinguish HCC and non-HCC normal cells for selective transgene expression control and killing of HCC cells.

BACKGROUND: Predicting lymph node metastasis (LNM) accurately is vital to design optimal treatment strategies preoperatively for gastric cancer (GC) patients. However, conventional tumor biomarkers and imaging techniques are not sufficient to predict LNM before surgery. miR-126 has been reported to play important roles in tumor metastasis which may represent a novel tumor biomarker.
OBJECTIVE: To assess the utility of the combination of serum miR-126 and multi-detector computed tomography (MDCT) in predicting LNM preoperatively in GC.
METHODS: Quantitative real-time polymerase chain reaction was performed to examine the serum miR-126 expression levels in 338 GC patients. MDCT was also performed. The cut-off value of preoperative serum miR-126 level for LNM was determined by receiver characteristic curve (ROC) analysis. Logistic regression analysis was used to determine independent predictors for LNM.
RESULTS: The serum miR-126 levels of GC patients with LNM were significantly lower compared with those without LNM (p< 0.05). In addition, the later the N stage was, the lower the serum miR-126 level was in GC patients (p< 0.05). With a cut-off value of 63.4, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of serum miR-126 for predicating LNM were 83.2%, 79.0%, 81.9%, 90.4% and 66.4%, respectively. The combination of serum miR-126 level and MDCT increased the accuracy of MDCT prediction for LNM from 69.2% to 86.7%. Serum miR-126 was an independent predictor for LNM.
CONCLUSIONS: These results indicate for the first time that the combination of serum miR-126 and MDCT is useful for the prediction of LNM in GC.

BACKGROUND: Low-dose computed tomography can identify smaller nodules more often than chest radiography in lung screening. However, complications from invasive diagnostic procedures performed to detect nodules are common. Exosomes contain a diverse array of biomolecules that reflect the biological state of the cell from which they are released. The aim of this study was to investigate the diagnostic value of bronchoalveolar lavage (BAL) fluid exosomal microRNAs (miRNAs) for early-stage lung adenocarcinoma.
METHODS: We evaluated miRNAs (miR-7, miR-21, miR-126, Let-7a, miR-17, and miR-19) known to have diagnostic value for lung adenocarcinoma. Exosomes were isolated from the BAL fluid of control subjects (n = 15) and patients with lung adenocarcinoma (n = 13). Exosomal miRNA was analyzed using a commercial kit containing probes targeting six selected miRNAs. Results were validated via quantitative PCR.
RESULTS: The presence of miRNAs was confirmed in exosomes from BAL fluid of both lung adenocarcinoma patients and control subjects. miR-126 (P < 0.001) and Let-7a (P = 0.015) levels were significantly higher in the BAL fluid of lung adenocarcinoma patients than in control subjects. The BAL fluid miRNA signature was confirmed using an independent set of paired adenocarcinoma and normal tissue samples (n = 4). Lung adenocarcinoma tissues showed increased expression of miR-126 (P = 0.039) compared to normal tissue samples.
CONCLUSION: We identified a close correlation between BAL fluid exosomal miRNAs and tumor miRNAs. BAL fluid exosomal miRNAs obtained through noninvasive methods could serve as diagnostic biomarkers in early-stage lung adenocarcinoma.

BACKGROUND: MicroRNAs (miRNAs) play an important role in cancer biology. Neoadjuvant radiochemotherapy followed by surgery is a standard treatment for locally advanced esophageal squamous cell carcinoma (ESCC). However, a subset of patients do not respond. We evaluated whether miRNA profiles can predict resistance to radiochemotherapy.
METHODS: Formalin-fixed, paraffin-embedded pretherapeutic biopsies of patients treated by radiochemotherapy followed by esophagectomy were analyzed. The response was determined by histopathological tumor regression grading. miRNA profiling was performed by microarray analysis (Agilent platform) in 16 non-responders and 15 responders. Differentially expressed miRNAs were confirmed by real-time quantitative PCR (qRT-PCR) in an expanded cohort of 53 cases.
RESULTS: The miRNA profiles within and between non-responders and responders were highly similar (r = 0.96, 0.94 and 0.95). However, 12 miRNAs were differentially expressed (> twofold; p ≤ 0.025): non-responders showed upregulation of hsa-miR-1323, hsa-miR-3678-3p, hsv2-miR-H7-3p, hsa-miR-194*, hsa-miR-3152, kshv-miR-K12-4-3p, hsa-miR-665 and hsa-miR-3659 and downregulation of hsa-miR-126*, hsa-miR-484, hsa-miR-330-3p and hsa-miR-3653. qRT-PCR analysis confirmed the microarray findings for hsa-miR-194* and hsa-miR-665 (p < 0.001 each) with AUC values of 0.811 (95% CI 0.694-0.927) and 0.817 (95% CI 0.704-0.930), respectively, in ROC analysis.
CONCLUSIONS: Our results indicate that miRNAs are involved in the therapeutic response in ESCC and suggest that miRNA profiles could facilitate pretherapeutic patient selection.

Malate Dehydrogenase (MDH) 1 has recently been shown to be highly expressed and display prognostic value in non-small cell lung carcinomas (NSCLCs). However, it is not known how MDH1 expression is regulated and there is no current molecular or chemical strategy that specifically targets MDH1. This may be due to structural and enzymatic similarities with its isoenzyme, malate dehydrogenase 2 (MDH2). However, MDH1 and MDH2 are encoded by distinct genes and this opens up the possibility for modulation at the expression level. Here, we screened in silico for microRNAs (miRs) that selectively targets the 3'UTR region of MDH1. These analyses revealed that mir-126-5p has three binding sites in the 3'UTR region of MDH1. Additionally, we show that expression of miR-126-5p suppresses the enzymatic activity of MDH1, mitochondrial respiration and caused cell death in NSCLC cell lines.