Aberrant miR-181b-5p and miR-486-5p expression in serum and tissue of non-small cell lung cancer

Exosomes from adipose-derived stem cells inhibits skin cancer progression via miR-199a-5p/SOX4

Although miR-199a-5p is linked to the development of numerous cancers, its regulatory role in skin cancer is unclear. In this work, the impact of miR-199a-5p produced by adipose-derived stem cells on malignant melanoma skin cancer was investigated.30 pair tumor tissues and adjacent tissues were obtained from skin cancer patients. Adipose-derived stem cell (ADSCs) were isolated from adipose tissues harvested from healthy subjects. The mRNA relative expression was evaluated via qRT-PCR. Cell proliferation ability was measured via CCK-8 assay. Apoptosis was evaluated via flow cytometry. The connection between miR-199a-5p and SOX4 was confirmed via luciferase reporter assay. Western blot was conducted to evaluate protein expression. MiR-199a-5p was higher expressed in ADSCs exosomes and was lower expressed in skin cancer tissues and cells. ADSCs-derived exosomes inhibited cell invasion of skin cancer. MiR-199a-5p inhibitor enhanced cell viability and invasion. In addition, miR-199a-5p inhibitor suppressed cell apoptosis. MiR-199a-5p NC transfected ADSCs inhibited cell viability and invasion while miR-199a-5p mimic transfected ADSCs further inhibited cell viability and invasion. In addition, miR-199a-5p NC transfected ADSCs enhanced cell apoptosis while miR-199a-5p mimic transfected ADSCs further enhanced cell apoptosis. Luciferase supported the targetscan prediction that miR-199a-5p might control SOX4 expression. SOX4 expression was noticeably lower in the miR-199a-5p mimic group.Exosomes from adipose-derived stem cells inhibited skin cancer progression via miR-199a-5p/SOX4.

MicroRNA-181b-5p Facilitates Thyroid Cancer Growth via Targeting Programmed Cell Death 4

To explore the potential mechanism of microRNA (miR)-181b-5p promoting the progression of thyroid cancer (TC) by targeting programmed cell death 4 (PDCD4). Analysis of miR-181b-5p and PDCD4 expression in TC was performed. The impact of miR-181b-5p and PDCD4 on proliferation, migration, invasion, and apoptosis of TC cells was examined. The binding relationship between miR-181b-5p and PDCD4 was predicted and verified. miR-181b-5p was up-regulated in TC, while PDCD4 was down-regulated. Down-regulating miR-181b-5p or up-regulating PDCD4 inhibited the proliferation, migration, and invasion of TC cells, and promoted cell apoptosis. PDCD4 was the downstream target of miR-181b-5p, and down-regulation of PDCD4 counteracted the inhibitory effect of down-regulation of miR-181b-5p on the proliferation, migration, and invasion of TC cells and the promoting effect on apoptosis. miR-181b-5p inhibits the proliferation, migration, and invasion of TC cells and promotes cell apoptosis by targeting PDCD4.

Advances in tumor microenvironment and underlying molecular mechanisms of bladder cancer: a systematic review

Bladder cancer is one of the most frequent malignant tumors of the urinary system. The prevalence of bladder cancer among men and women is roughly 5:2, and both its incidence and death have been rising steadily over the past few years. At the moment, metastasis and recurrence of advanced bladder cancer-which are believed to be connected to the malfunction of multigene and multilevel cell signaling network-remain the leading causes of bladder cancer-related death. The therapeutic treatment of bladder cancer will be greatly aided by the elucidation of these mechanisms. New concepts for the treatment of bladder cancer have been made possible by the advancement of research technologies and a number of new treatment options, including immunotherapy and targeted therapy. In this paper, we will extensively review the development of the tumor microenvironment and the possible molecular mechanisms of bladder cancer.

Identification and clinical value of a new ceRNA axis (TIMP3/hsa-miR-181b-5p/PAX8-AS1) in thyroid cancer

Background

Thyroid cancer (TC) is a prevalent and increasingly common malignant tumor. In most cases, TC progresses slowly and runs a virtually benign course. However, challenges remain with the treatment of refractory TC, which does not respond to traditional management or is subject to relapse or metastasis. Therefore, new therapeutic regimens for TC patients with poor outcomes are urgently needed.

Methods

The differentially expressed RNAs were identified from the expression profile data of RNA from TC downloaded from The Cancer Genome Atlas database. Multiple databases were utilized to investigate the regulatory relationship among RNAs. Subsequently, a competitive endogenous RNA (ceRNA) network was established to elucidate the ceRNA axis that is responsible for the clinical prognosis of TC. To understand the potential mechanism of ceRNA axis in TC, location analysis, functional enrichment analysis, and immune-related analysis were conducted.

Results

A ceRNA network of TC was constructed, and the TIMP3/hsa-miR-181b-5p/PAX8-AS1 ceRNA axis associated with the prognosis of TC was successfully identified. Our results showed that the axis might influence the prognosis of TC through its regulation of regulating tumor immunity.

Conclusions

Our findings provide evidence that TIMP3/hsa-miR-181b-5p/PAX8-AS1 axis is significantly related to the prognosis of TC. The molecules involved in this axis may serve as novel therapeutic approaches for TC treatment.

Liquid Biopsy for Lung Cancer: Up-to-Date and Perspectives for Screening Programs

Lung cancer is the deadliest cancer worldwide. Tissue biopsy is currently employed for the diagnosis and molecular stratification of lung cancer. Liquid biopsy is a minimally invasive approach to determine biomarkers from body fluids, such as blood, urine, sputum, and saliva. Tumor cells release cfDNA, ctDNA, exosomes, miRNAs, circRNAs, CTCs, and DNA methylated fragments, among others, which can be successfully used as biomarkers for diagnosis, prognosis, and prediction of treatment response. Predictive biomarkers are well-established for managing lung cancer, and liquid biopsy options have emerged in the last few years. Currently, detecting EGFR p.(Tyr790Met) mutation in plasma samples from lung cancer patients has been used for predicting response and monitoring tyrosine kinase inhibitors (TKi)-treated patients with lung cancer. In addition, many efforts continue to bring more sensitive technologies to improve the detection of clinically relevant biomarkers for lung cancer. Moreover, liquid biopsy can dramatically decrease the turnaround time for laboratory reports, accelerating the beginning of treatment and improving the overall survival of lung cancer patients. Herein, we summarized all available and emerging approaches of liquid biopsy-techniques, molecules, and sample type-for lung cancer.

Recent strategies for electrochemical sensing detection of miRNAs in lung cancer

MicroRNAs (miRNAs) associated with lung cancer are diversifying. MiR-21, Let-7, and miR-141 are common diagnostic targets. Some new lung cancer miRNAs, such as miR-25, miR-145, and miR-126, have received increasing attention. Although various techniques are available for the analysis of lung cancer miRNAs, electrochemistry has been recognized for its high sensitivity, low cost, and rapid response. However, how to realize the signal amplification is one of the most important contents in the design of electrochemical biosensors. Herein, we mainly introduce the amplification strategy based on enzyme-free amplification and signal conversion, including non-linear HCR, catalytic hairpin assembly (CHA), electrochemiluminescence (ECL), and Faraday cage. Furthermore, new progress has emerged in the fields of nanomaterials, low oxidation potential, and simultaneous detection of multiple targets. Finally, we summarize some new challenges that electrochemical techniques may encounter in the future, such as improving single-base discrimination ability, shortening electrochemical detection time, and providing real body fluid samples assay.

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.

Anesthetic propofol enhances cisplatin-sensitivity of non-small cell lung cancer cells through N6-methyladenosine-dependently regulating the miR-486-5p/RAP1-NF-κB axis

BACKGROUND

Drug resistance is a considerable challenge for chemotherapy in non-small cell lung cancer (NSCLC). Propofol, a commonly used intravenous anesthetics, has been reported to suppress the malignancy of various cancers. However, the effects of propofol on cisplatin (DDP) sensitivity in NSCLC and its molecular mechanisms have not been clearly clarified yet, and the present study aimed to resolve this problem.

METHODS

NSCLC cells were co-treated with propofol and DDP, Cell Counting kit-8 assay, colony formation assay and flow cytometry were conducted to test the role of propofol in regulating DDP-resistance in NSCLC. Next, through conducting quantitative real-time polymerase chain reaction, dual-luciferase gene reporter system and western blot, the responsible molecular axis in propofol regulating the DDP sensitivity in NSCLC was uncovered, and the function verification experiments were performed by transfection with the inhibitors or small interfering RNAs of those molecules.

RESULTS

Propofol suppressed cell viability, colony formation ability, tumorigenesis, and promoted cell apoptosis to enhance DDP-sensitivity in NSCLC in vitro and in vivo. Propofol increased miR-486-5p level in NSCLC cells and xenograft tumors tissues in a N6-methyladenosine (m6A)-dependent manner, thus inactivating the Ras-associated protein1 (RAP1)-NF-kappaB (NF-κB) axis. Propofol regulated the miR-486-5p/RAP1-NF-κB axis to improve DDP-sensitivity in NSCLC.

CONCLUSIONS

Taken together, this study firstly investigates the detailed molecular mechanisms by which propofol enhanced DDP-sensitivity in NSCLC cells, and a novel m6A-dependent miR-486-5p/RAP1-NF-κB axis is identified to be closely associated with the process.

MicroRNA-181a-5p Promotes Osteosarcoma Progression via PTEN/AKT Pathway

Osteosarcoma is the most common primary malignant bone tumor in children and adolescents with poor prognosis. MicroRNA-181a-5p (miR-181a-5p) is involved in the progression of various tumors; however, its role and underlying mechanism in osteosarcoma remains unclear. In this study, we found that miR-181a-5p was upregulated in human osteosarcoma cells and tissues. miR-181a-5p mimic significantly promoted, while miR-181a-5p inhibitor blocked the proliferation, colony formation, migration, invasion, and cell cycle progression of osteosarcoma cells. Mechanistically, miR-181a-5p bound to the 3′-untranslational region of phosphatase and tensin homolog (PTEN) and reduced its protein expression, thereby activating protein kinase B (PKB/AKT) pathway. Either PTEN overexpression or AKT inhibition notably blocked the tumor-promoting effects of miR-181a-5p. Moreover, we observed that miR-181a-5p mimic further inhibited growth of human osteosarcoma cells in the presence of adriamycin or cisplatin. Overall, miR-181a-5p promotes osteosarcoma progression via PTEN/AKT pathway and it is a promising therapeutic target to treat osteosarcoma.

Computational pathology aids derivation of microRNA biomarker signals from Cytosponge samples

BACKGROUND

Non-endoscopic cell collection devices combined with biomarkers can detect Barrett's intestinal metaplasia and early oesophageal cancer. However, assays performed on multi-cellular samples lose information about the cell source of the biomarker signal. This cross-sectional study examines whether a bespoke artificial intelligence-based computational pathology tool could ascertain the cellular origin of microRNA biomarkers, to inform interpretation of the disease pathology, and confirm biomarker validity.

METHODS

The microRNA expression profiles of 110 targets were assessed with a custom multiplexed panel in a cohort of 117 individuals with reflux that took a Cytosponge test. A computational pathology tool quantified the amount of columnar epithelium present in pathology slides, and results were correlated with microRNA signals. An independent cohort of 139 Cytosponges, each from an individual patient, was used to validate the findings via qPCR.

FINDINGS

Seventeen microRNAs are upregulated in BE compared to healthy squamous epithelia, of which 13 remain upregulated in dysplasia. A pathway enrichment analysis confirmed association to neoplastic and cell cycle regulation processes. Ten microRNAs positively correlated with columnar epithelium content, with miRNA-192-5p and -194-5p accurately detecting the presence of gastric cells (AUC 0.97 and 0.95). In contrast, miR-196a-5p is confirmed as a specific BE marker.

INTERPRETATION

Computational pathology tools aid accurate cellular attribution of molecular signals. This innovative design with multiplex microRNA coupled with artificial intelligence has led to discovery of a quality control metric suitable for large scale application of the Cytosponge. Similar approaches could aid optimal interpretation of biomarkers for clinical use.

FUNDING

Funded by the NIHR Cambridge Biomedical Research Centre, the Medical Research Council, the Rosetrees and Stoneygate Trusts, and CRUK core grants.

Hormonally Regulated Myogenic miR-486 Influences Sex-specific Differences in Cancer-induced Skeletal Muscle Defects

Cancer-induced skeletal muscle defects show sex-specific differences in severity with men performing poorly compared to women. Hormones and sex chromosomal differences are suggested to mediate these differences, but the functional skeletal muscle markers to document these differences are unknown. We show that the myogenic microRNA miR-486 is a marker of sex-specific differences in cancer-induced skeletal muscle defects. Cancer-induced loss of circulating miR-486 was more severe in men with bladder, lung, and pancreatic cancers compared to women with the same cancer types. In a syngeneic model of pancreatic cancer, circulating and skeletal muscle loss of miR-486 was more severe in male mice compared to female mice. Estradiol (E2) and the clinically used selective estrogen receptor modulator toremifene increased miR-486 in undifferentiated and differentiated myoblast cell line C2C12 and E2-inducible expression correlated with direct binding of estrogen receptor alpha (ERα) to the regulatory region of the miR-486 gene. E2 and toremifene reduced the actions of cytokines such as myostatin, transforming growth factor β, and tumor necrosis factor α, which mediate cancer-induced skeletal muscle wasting. E2- and toremifene-treated C2C12 myoblast/myotube cells contained elevated levels of active protein kinase B (AKT) with a corresponding decrease in the levels of its negative regulator PTEN, which is a target of miR-486. We propose an ERα:E2-miR-486-AKT signaling axis, which reduces the deleterious effects of cancer-induced cytokines/chemokines on skeletal muscle mass and/or function.

Pulmonary MicroRNA Changes Alter Angiogenesis in Chronic Obstructive Pulmonary Disease and Lung Cancer

The pulmonary endothelium is dysfunctional in chronic obstructive pulmonary disease (COPD), a known risk factor for lung cancer. The pulmonary endothelium is altered in emphysema, which is disproportionately affected by cancers. Gene and microRNA expression differs between COPD and non-COPD lung. We hypothesised that the alteration in microRNA expression in the pulmonary endothelium contributes to its dysfunction. A total of 28 patients undergoing pulmonary resection were recruited and endothelial cells were isolated from healthy lung and tumour. MicroRNA expression was compared between COPD and non-COPD patients. Positive findings were confirmed by quantitative polymerase chain reaction (qPCR). Assays assessing angiogenesis and cellular migration were conducted in Human Umbilical Vein Endothelial Cells (n = 3-4) transfected with microRNA mimics and compared to cells transfected with negative control RNA. Expression of miR-181b-3p, miR-429 and miR-23c (all p < 0.05) was increased in COPD. Over-expression of miR-181b-3p was associated with reduced endothelial sprouting (p < 0.05). miR-429 was overexpressed in lung cancer as well and exhibited a reduction in tubular formation. MicroRNA-driven changes in the pulmonary endothelium thus represent a novel mechanism driving emphysema. These processes warrant further study to determine if they may be therapeutic targets in COPD and lung cancer.

miR-181b-5p Promotes the Progression of Cholangiocarcinoma by Targeting PARK2 via PTEN/PI3K/AKT Signaling Pathway

This study combined with bioinformatics analysis and investigated the expression pattern of miR-181b-5p, as well as explored its role and mechanism in cholangiocarcinoma (CCA or CHOL). Several bioinformatics databases were used to analyze the expression of miR-181b and the enrichment of miR-181b in biological activities and biological pathways in CCA. The RT-qPCR analysis was used to examine the expression levels of miR-181b-5p. A receiver operation characteristics (ROC) curve analysis and the Kaplan-Meier survival assay were conducted to validate the diagnostic and prognostic implication of miR-181b-5p. Cell experiments were used to explore the possible functional role of miR-181b-5p in CCA progression. The bioinformatics assay was used to predict the target gene of miR-181b-5p and Western blot was used to confirm the related signaling pathway. The bioinformatics analysis results suggest that miR-181b-5p was highly expressed in cholangiocarcinoma and its expression was negatively related to PARK2 expression in CCA tissues. miR-181b-5p expression in the serum and tissues was upregulated and associated with lymph node metastasis and TNM stage. Increased expression of miR-181b-5p had relatively high diagnostic accuracy and showed poor prognosis in CCA patients. In addition, miR-181b-5p overexpression enhanced cell proliferation, migration, and invasion by targeting PARK2. Overexpression of miR-181b-5p activated the PI3K/AKT signaling pathway, while knockdown of miR-181b-5p suppressed the signaling pathway. Increased expression of miR-181b-5p in CCA may be a potential diagnostic or/and prognostic indicator for CCA patients. The present data indicated miR-181b-5p acted as an oncogene in CCA through promoting tumor cell proliferation, migration, and invasion of CCA via the PTEN/PI3K/AKT signaling pathway by targeting PARK2, which might be a promising therapeutic target or biomarker for CCA.

Cisatracurium inhibits the growth and induces apoptosis of ovarian cancer cells by promoting lincRNA-p21

As a common muscle relaxant, cisatracurium has shown good antitumor effect on some tumors. Recent studies reported that cisatracurium could inhibit the progression of colon cancer by upregulating tumor suppressor gene p53. However, its role in ovarian cancer and its regulatory effect on p53 and p53 downstream targeting gene long intergenic noncoding RNA p21 (lincRNA-p21) is still unknown. Quantitative Real-time Polymerase Chain Reaction (qRT-PCR) was used to assess the expression of p53, lincRNA-p21 and miR-181b. Cell viability and proliferation were detected by CCK-8 assay and Edu staining, respectively. Wound-healing and Transwell assays were performed to determine the abilities of cell migration and invasion. Apoptosis was evaluated by TUNEL staining. Luciferase reporter assay was conducted to detect the relationship between lincRNA-p21 and miR-181b. As a result, cisatracurium could increase the expressions of p53 and lincRNA-p21 of ovarian cancer cell line (OVCAR-3) in a dose-dependent manner. In addition, cisatracurium significantly inhibited the proliferation, migration and invasion of OVACR-3 cells, and induced apoptosis. However, these above changes in biological function can be attenuated by lincRNA-p21 knockdown. Next, lincRNA-p21 could directly target miR-181b and negatively regulate its expression by luciferase reporter assay. In conclusion, cisatracurium inhibited the progression of OVCAR-3 cells through upregulation of lincRNA-p21 expression activated by p53 inhibiting miR-181b expression. The experimental results provide a new research idea for the application of cisatracurium in ovarian cancer.

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.

CircCSNK1G3 up-regulates miR-181b to promote growth and metastasis via TIMP3-mediated epithelial to mesenchymal transitions in renal cell carcinoma

Renal cell carcinoma (RCC) is the most common form of kidney cancer, with a high recurrence rate and metastasis capacity. Circular RNAs (circRNAs) have been suggested to act as the critical regulator in several diseases. This study is designed to investigate the role of circCSNK1G3 on RCC progression. We observed a highly expression of circCSNK1G3 in RCC tissues compared with normal tissues. The aberrantly circCSNK1G3 promoted the tumour growth and metastasis in RCC. In the subsequent mechanism investigation, we discovered that the tumour‐promoting effects of circCSNK1G3 were, at least partly, achieved by up‐regulating miR‐181b. Increased miR‐181b inhibits several tumour suppressor gene, including CYLD, LATS2, NDRG2 and TIMP3. Furthermore, the decreased TIMP3 leads to the enhanced epithelial to mesenchymal transition (EMT) process, thus promoting the cancer metastasis. In conclusion, we identified the oncogenic role of circCSNK1G3 in RCC progression and demonstrated the regulatory role of circCSNK1G3 induced miR‐181b expression, which leads to TIMP3‐mediated EMT process, thus resulting in tumour growth and metastasis in RCC. This study reveals the promise of circCSNK1G3 to be developed as a potential diagnostic and prognostic biomarker in the clinic. And the roles of circCSNK1G3 in cancer research deserve further investigation.

Regulation of breast cancer metastasis signaling by miRNAs

Despite the decline in death rate from breast cancer and recent advances in targeted therapies and combinations for the treatment of metastatic disease, metastatic breast cancer remains the second leading cause of cancer-associated death in U.S. women. The invasion-metastasis cascade involves a number of steps and multitudes of proteins and signaling molecules. The pathways include invasion, intravasation, circulation, extravasation, infiltration into a distant site to form a metastatic niche, and micrometastasis formation in a new environment. Each of these processes is regulated by changes in gene expression. Noncoding RNAs including microRNAs (miRNAs) are involved in breast cancer tumorigenesis, progression, and metastasis by post-transcriptional regulation of target gene expression. miRNAs can stimulate oncogenesis (oncomiRs), inhibit tumor growth (tumor suppressors or miRsupps), and regulate gene targets in metastasis (metastamiRs). The goal of this review is to summarize some of the key miRNAs that regulate genes and pathways involved in metastatic breast cancer with an emphasis on estrogen receptor α (ERα+) breast cancer. We reviewed the identity, regulation, human breast tumor expression, and reported prognostic significance of miRNAs that have been documented to directly target key genes in pathways, including epithelial-to-mesenchymal transition (EMT) contributing to the metastatic cascade. We critically evaluated the evidence for metastamiRs and their targets and miRNA regulation of metastasis suppressor genes in breast cancer progression and metastasis. It is clear that our understanding of miRNA regulation of targets in metastasis is incomplete.

Evaluation of the mir-126, mir-182, and mir-486-5p Expression Signature of Head and Neck Squamous Cell Carcinomas and Lung Squamous Cell Carcinomas

OBJECTIVE

Although squamous cell carcinomas (SCCs) originating from different anatomic localizations display a similar histological appearance under light microscopy, they may differ in terms of epigenetic and genetic features. The aim of this study was to analyze mir-126, mir-182, and mir-486-5p expression levels in head and neck SCCs and lung SCCs, and to identify localization-specific miRNA expression profiles.

MATERIAL AND METHOD

The expression levels of mir-126, mir-182, and mir-486-5p were analyzed in lung, oral cavity, laryngeal, and hypopharyngeal SCCs in 40 patients, using quantitative real-time polymerase chain reaction.

RESULTS

The findings showed that lung, oral cavity, laryngeal, and hypopharyngeal SCCs have distinct mir-126 and mir-486-5p expression profiles. It was also observed that mir-126 and mir-486-5p expression levels were highly specific to the tumor localization.

CONCLUSION

These findings highlighted that SCCs originating from different anatomic localizations have different miRNA expression profiles. miRNA expression analysis can be used to predict the primary localizations of those SCCs.

LncRNA ST7-AS1, by regulating miR-181b-5p/KPNA4 axis, promotes the malignancy of lung adenocarcinoma

Background

Growing evidence suggests that suppressor of tumorigenicity 7 antisense RNA 1 (ST7-AS1) is an oncogenic long noncoding RNA (lncRNA). However, little is known on its clinical significance, biological functions, or molecular mechanisms in lung adenocarcinoma (LUAD).

Methods

The expression of ST7-AS1 and miR-181b-5p were examined by qRT-PCR. The correlations between ST7-AS1 level and different clinicopathological features were analysed. In vitro, LUAD cells were examined for cell viability, migration and invasion by MTT, wound healing and Transwell assay, respectively. Epithelial-mesenchymal transition (EMT) biomarkers were detected by Western blot. The regulations between ST7-AS1, miR-181b-5p, and KPNA4 were examined by luciferase assay, RNA immunoprecipitation, RNA pulldown. Both gain- and loss-of-function strategies were used to assess the importance of different signalling molecules in malignant phenotypes of LUAD cells. The in vivo effect was analysed using the xenograft and the experimental metastasis mouse models.

Results

ST7-AS1 was upregulated in LUAD tissues or cell lines, correlated with tumours of positive lymph node metastasis or higher TNM stages, and associated with shorter overall survival of LUAD patients. ST7-AS1 essentially maintained the viability, migration, invasion, and EMT of LUAD cells. The oncogenic activities of ST7-AS1 were accomplished by sponging miR-181b-5p and releasing the suppression of the latter on KPNA4. In LUAD tissues, ST7-AS1 level positively correlated with that of KPNA4 and negatively with miR-181b-5p level. In vivo, targeting ST7-AS1 significantly inhibited xenograft growth and metastasis.

Conclusions

ST7-AS1, by regulating miR-181b-5p/KPNA4 axis, promotes the malignancy of LUAD cells. Targeting ST7-AS1 and KPNA4 or up-regulating miR-181b-5p, therefore, may benefit the treatment of LUAD.

MiR-122 is involved in immune response by regulating Interleukin-15 in the orange-spotted grouper (Epinephelus coioides)

Epinephelus coioides is an important economic culture marine fish and is susceptible to various pathogenic diseases. Increasingly evidences showed that miRNAs participated in the regulation of the cell proliferation, differentiation and immune response. MiR-122 has been reported to play an essential role in immune response by triggering an inflammatory reaction. However, the function of miR-122 in response to bacterial infection is unclear in Epinephelus coioides. Herein, we report that miR-122 is involved in response to Aeromonas hydrophila infection of grouper spleen cells (GS). IL-15, IL-6 and IL-1β are inhibited in overexpression miR-122 GS cells, while induced in silence miR-122 GS cells. In addition, IL-15 is predicted to be the target gene of miR-122, which is further confirmed by LUC. Taken together, we propose that miR-122 regulates the immune response to bacterial infection by triggering IL-15.

LncRNA LUCAT1/miR-181a-5p axis promotes proliferation and invasion of breast cancer via targeting KLF6 and KLF15

BACKGROUND

Long non-coding RNAs (lncRNAs) are novel regulatory molecules in breast cancer development. LncRNA LUCAT1 is a potential tumor promoter in human cancers. In this study, we aimed to explore the role of LUCAT1 in human breast cancer tissues and cells.

METHODS

A total of 31 breast cancer patients who underwent tumor resection, but without chemo- or radiotherapy or acute lung/heart/kidney diseases, provided tumor and adjacent normal tissues. Bioinformatic analysis, qRT-PCR, and luciferase reporter assay were carried out during the study.

RESULTS

qRT-PCR analysis indicated that, compared with the adjacent tissues and MCF-10A normal breast epithelial cells, LUCAT1 was markedly up-regulated in the breast cancer tissues and five BC cell lines, including MDA-MB-231, MDA-MB-468, MDA-MB-435, SKBR3, and MCF-7. The knockdown of LUCAT1, through the transfection of small interfering RNA (siRNA) specific to LUCAT1, resulted in inhibition of proliferation in breast cancer cells. The expression levels of miR-181a-5p were decreased in the breast cancer tissues and five BC cell lines. Bioinformatic analysis and luciferase reporter assay suggested the interaction between miR-181a-5p and LUCAT1. In addition, the effects of LUCAT1 on promoting cell proliferation were attenuated by overexpression of miR-181a-5p through the transfection of miR-181a-5p mimic. Moreover, bioinformatics and luciferase reporter assay confirmed that miR-181a-5p targeted the 3'-UTR region of KLF6 and KLF15 mRNA, which were two tumor suppressor genes. LUCAT1/miR-181a-5p axis regulated the expression of KLF6 and KLF15 both in vitro and in vivo.

CONCLUSIONS

Our data indicate that LUCAT1/miR-181a-5p axis can serve as a novel therapeutic target in breast cancer.

Effects of endurance racing on horse plasma extracellular particle miRNA

BACKGROUND

Physical exercise is an essential factor in preventing and treating metabolic diseases by promoting systemic benefits throughout the body. The molecular factors involved in this process are poorly understood. Micro RNAs (miRNAs) are small non-coding RNAs that inhibit mRNA transcription. MiRNAs, which can participate in the benefits of exercise to health, circulate in plasma in extracellular particles (EP). Horses that undergo endurance racing are an excellent model to study the impact of long-duration/low intensity exercise in plasma EP miRNAs.

OBJECTIVES

To evaluate the effects of 160 km endurance racing on horse plasma extracellular particles and their miRNA population.

STUDY DESIGN

Cohort study.

METHODS

We collected plasma from five Arabian horses during five time-points of an endurance ride. Extracellular particles were purified from plasma and characterised by electron microscopy, resistive pulse sensing (qNano) and western blotting. Small RNAs were purified from horse plasma EP, and sequencing was performed.

RESULTS

Endurance racing increased EP concentration and average diameter compared to before the race. Western blotting showed a high concentration of extracellular vesicles proteins 2 hours after the race, which returned to baseline 15 hours after the race. MicroRNA differential expression analysis revealed increasing levels of eca-miR-486-5p during and after the race, and decreasing levels of eca-miR-9083 after the end.

CONCLUSIONS

This study adds new data about the variation in plasma EP concentrations after long-distance exercise and brings new insights about the roles of exercise-derived EP miRNAs during low-intensity endurance exercise.

Plasma RNA sequencing of extracellular RNAs reveals potential biomarkers for non-small cell lung cancer

BACKGROUND

Lung cancer is one of the most common malignancies, and it has extremely high incidence and mortality rates. Although there have been many studies focused on lung cancer biomarkers, few have reported the extracellular RNA profiles of lung cancer. In this study, we used RNA-seq technology to analyze extracellular RNAs in low volume peripheral blood plasma; we compared the differentially expressed genes from the plasma of non-small cell lung cancer (NSCLC) patients with that of healthy controls.

METHODS

We used RNA-seq technology and bioinformatics to analyze the extracellular RNA (exRNA) sequences of 12 human plasma samples (500 μl per sample), 6 from NSCLC patients and 6 from healthy controls. Subsequently, we used gene ontology (GO) enrichment, KEGG analysis and coexpression experiments to compare the differentially expressed genes (DEGs) and identify tumor biomarkers that were highly correlated with NSCLC. These DEGs were further verified by quantitative PCR.

RESULTS

Approximately 20 million clean reads were produced for each plasma sample; 50-80% of the reads aligned to the human references, and hundreds of thousands of reads were counted in each plasma sample. In addition, a total of 640 genes (368 upregulated and 272 downregulated) were differentially expressed between NSCLC plasma and normal plasma. Further, we identified 7 key DEGs that are highly correlated with lung tumorigenesis: COX1, COX2, COX3, ND1, ND2, ND4L, and ATP6.

CONCLUSION

exRNA-seq from a small amount (400-500 μl) of plasma opens new possibilities for exploring lung cancer biomarkers in the plasma.

Characterization of serum small extracellular vesicles and their small RNA contents across humans, rats, and mice

Serum small extracellular vesicles (sEVs) have recently drawn considerable interest because of the diagnostic and therapeutic potential of their miRNAs content. However, the characteristics of human, mouse and rat serum sEVs and their differences in small RNA contents are still unknown. In this study, through nanoparticle tracking analysis and small RNA sequencing, we found that human, rat, and mouse serum sEVs exhibited distinct sizes and particle numbers as well as small RNA contents. Serum sEVs contained not only abundant miRNAs but also a large number of tRNA fragments. Most serum miRNAs existed both inside and outside of sEVs but were enriched in sEVs. Common serum sEV miRNAs (188 miRNAs) and species-specific serum sEV miRNAs (265, 58, and 159 miRNAs, respectively) were identified in humans, rats, or mice. The serum sEVs contained miRNAs from tissues and organs throughout the body, with blood cells as the main contributors. In conclusion, our findings confirmed the rationality of exploring serum sEV miRNAs as noninvasive diagnostic markers and revealed great differences in serum sEV small RNAs between humans, rats, and mice. Inadequate attention to these differences and the contribution of blood cells to serum sEV miRNAs could hinder the clinical translation of basic studies.

Combination of Serum miRNAs with Serum Exosomal miRNAs in Early Diagnosis for Non-Small-Cell Lung Cancer

Purpose

Circulating microRNAs (miRNAs) have shown the potential for non-invasive diagnosis of various types of malignancies at an early stage. The aim of the study was to explore the feasibility of a combination of 8 serum miRNAs related to non-small-cell lung cancer (NSCLC) with the corresponding serum exosomal miRNAs in early diagnosis for the patients with NSCLC.

Methods

We measured 8 serum miRNAs and the corresponding serum exosomal miRNAs including miR-21-5p, miR-126-3p, miR-141-3p, miR-146a-5p, miR-155-5p, miR-222-3p, miR-223-3p, and miR-486-5p in 48 patients with early NSCLC at stages I/II, 32 patients with lung benign lesion (LBL), and 48 healthy control (HC) by quantitative real-time polymerase chain reaction (qRT-PCR).

Results

The expression levels of 4 serum miRNAs including miR-21-5p, miR-141-3p, miR-222-3p, and miR-486-5p, and 2 serum exosomal miRNAs including miR-146a-5p and miR-486-5p in the early NSCLC group were significantly different from that in the LBL group and the HC group (P < 0.01). The areas under the receiver operating characteristic curves (AUC) of the 4 serum miRNAs and 2 serum exosomal miRNAs in the early NSCLC group were ≥0.697, of which serum exosomal miR-146a-5p and miR-486-5p were 0.813 and 0.886, respectively, and higher than that of the 4 serum miRNAs. Additionally, a combination of 4 serum miRNAs with 2 serum exosomal miRNAs improved the AUC to 0.960 for the patients with NSCLC at early stages, with a sensitivity of 85.42% and a specificity of 92.50%.

Conclusion

This study suggests that serum exosomal miRNAs other than serum miRNAs might be preferable biomarkers for the patients with NSCLC at early stages, and a combination of serum miRNAs with serum exosomal miRNAs contributes to the further improvement of early diagnosis for NSCLC.

MicroRNA-1298 is downregulated in non-small cell lung cancer and suppresses tumor progression in tumor cells

BACKGROUND

MicroRNAs (miRNAs) have been reported to serve pivotal roles in tumorigenesis. This study sough to assess the expression and clinical significance of microRNA-1298 (miR-1298) in patients with non-small cell lung cancer (NSCLC), and explore the functional role of miR-1298 in tumorigenesis.

METHODS

One hundred and twenty-one NSCLC patients were recruited in this study. The expression of miR-1298 was estimated using quantitative real-time PCR. Kaplan-Meier survival curves and Cox regression analysis were used to evaluate the prognostic value of miR-1298. Gain- and loss-of-function experiments were preformed to explore the biological function of miR-1298 in NSCLC cells.

RESULTS

Expression levels of miR-1298 were downregulated in NSCLC tissues and cells compared with the corresponding normal controls. The decreased expression of miR-1298 was associated with patients' lymph node metastasis and TNM stage. The low expression of miR-1298 predicted poor overall survival and served as an independent prognostic indicator in NSCLC patients. According to the cell experiments, NSCLC cell proliferation, migration and invasion were inhibited by the overexpression of miR-1298.

CONCLUSION

All the data indicated that the downregulation of miR-1298 predicts poor prognosis of NSCLC, and the overexpression of miR-1298 in NSCLC cells leads to inhibited tumorigenesis. The aberrant miR-1298 may serve as a novel biomarker and therapeutic target in NSCLC.

Altered expression of miR-181 affects cell fate and targets drug resistance-related mechanisms

MicroRNAs (miRNAs) are non-coding transcripts which regulate genetic and epigenetic events by interfering with mRNA translation. miRNAs are involved in regulation of cell fate due to their ability of interfering with physiological or pathological processes. In this review paper, we evaluate the role of miR-181 family members as prognostic or diagnostic markers or therapeutic targets in malignant pathologies in connection with the main hallmarks of cancer that are modulated by the family. Also, we take over the dual role of this family in dependency with the tumour suppressor and oncogenic features presented in cell and cancer type specific manner. Restoration of the altered expression levels contributes to the activation of cell death pathways or to a reduction in the invasion and migration mechanism; moreover, the mechanism of drug resistance is also modulated by miR-181 sequences with important applications in therapeutic strategies for malignant cells sensitisation. Overall, the main miR-181 family regulatory mechanisms are presented in a cancer specific context, emphasizing the possible clinical application of this family in terms of novel diagnosis and therapy approaches.

Molecular characterization of lung cancer: A two-miRNA prognostic signature based on cancer stem-like cells related genes

Lung cancer is one of the deadliest cancers worldwide. To increase the survival rate of lung cancer, it is necessary to explore specific prognosis markers. More and more evidence finds that noncoding RNA is closely associated with the survival of lung cancer, and cancer stem cells (CSCs) also play a significant role in the progress of lung cancer. The objective of this study is to find CSLCs genes that affect the prognosis of lung cancer. The differential expression of long noncoding RNAs (lncRNAs), microRNAs (miRNAs), messenger RNAs (mRNAs) in the Cancer Genome Atlas (TCGA) database and differential expression data from microarray of CD326⁺ and CD326^- A549 cell are intersected to identify stable and consistent expression genes (2 lncRNAs, 15 miRNAs, and 134 mRNAs). The intersection of lncRNAs and miRNAs is analyzed by univariate and multivariate Cox regression to obtained prognostic genes. Two miRNAs (miR-30b-5p and miR-29c-3p) are significantly correlated with the overall survival rate. Then using these two miRNAs to construct a risk score model as a prognosis signature of lung cancer. Subsequently, we analyzed the association between two miRNAs and clinical information of lung cancer patients, of which T stage, Neoplasm cancer and risk score (P < .05) can be used as independent prognostic indicators of lung cancer. Finally, target genes of 2 miRNAs and 134 mRNAs were annotated with Gene Ontology and analyzed with Kyoto Encyclopedia of Genes and Genomes pathway, and verified with the GEO database. In summary, this study illustrates the role of miRNAs in the promotion of lung cancer by CSCs, which is important to find molecular biomarkers of lung cancer.

miR-181b/Oncostatin m axis inhibits prostate cancer bone metastasis via modulating osteoclast differentiation

The activation of osteoblasts is significantly correlated to prostate tumor bone metastasis and bone loss. Oncostatin M (OSM) could promote breast cancer metastasis to bone. However, its role and mechanism in prostate cancer bone metastasis remain unclear. MicroRNAs (miRNAs) could play important roles in cancers via post-transcriptionally regulating target genes via binding to specific sequences in the 3' UTR of downstream target genes. In the present study, we performed microarray profiling analyses to identify differentially-expressed miRNAs in preosteoclast before and after osteoclast differentiation that could target OSM. miR-181b-5p was downregulated during Raw264.7 cells differentiation into osteoclast. By direct targeting OSM 3' UTR, miR-181b-5p inhibited OSM messenger RNA expression and protein levels, subsequently decreasing IL-6 and AREG and increasing OPG, while OSM overexpression exerted an opposing effect. More importantly, co-culture with miR-181b-5p-overexpressing differentiated Raw264.7 cells suppressed proliferation, migration, and invasion of mouse prostate cancer RM-1 cells, while co-culture with OSM-overexpressing Raw264.7 cells led to opposing cellular effects. More importantly, the effects of miR-181b-5p on osteoclastogenic factors and RM-1 cells could be significantly reversed by OSM overexpression. In summary, miR-181b-5p/OSM axis could be a viable therapeutic target for patients with surgically removed primary tumors to reduce bone metastasis and prevent bone loss.

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.

Exosomal miR-181b-5p Downregulation in Ascites Serves as a Potential Diagnostic Biomarker for Gastric Cancer-associated Malignant Ascites

Purpose

Peritoneal carcinomatosis in gastric cancer (GC) patients results in extremely poor prognosis. Malignant ascites samples are the most appropriate biological material to use to evaluate biomarkers for peritoneal carcinomatosis. This study identified exosomal MicroRNAs (miRNAs) differently expressed between benign liver cirrhosis-associated ascites (LC-ascites) and malignant gastric cancer-associated ascites (GC-ascites), and validated their role as diagnostic biomarkers for GC-ascites.

Materials and Methods

Total RNA was extracted from exosomes isolated from 165 ascites samples (73 LC-ascites and 92 GC-ascites). Initially, microarrays were used to screen the expression levels of 2,006 miRNAs in the discovery cohort (n=22). Subsequently, quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) analyses were performed to validate the expression levels of selected exosomal miRNAs in the training (n=70) and validation (n=73) cohorts. Furthermore, carcinoembryonic antigen (CEA) levels were determined in ascites samples.

Results

The miR-574-3p, miR-181b-5p, miR-4481, and miR-181d were significantly downregulated in the GC-ascites samples compared to the LC-ascites samples, and miR-181b-5p showed the best diagnostic performance for GC-ascites (area under the curve [AUC]=0.798 and 0.846 for the training and validation cohorts, respectively). The diagnostic performance of CEA for GC-ascites was improved by the combined analysis of miR-181b-5p and CEA (AUC=0.981 and 0.946 for the training and validation cohorts, respectively).

Conclusions

We identified exosomal miRNAs capable of distinguishing between non-malignant and GC-ascites, showing that the combined use of miR-181b-5p and CEA could improve diagnosis.

MiR-486-5p Serves as a Good Biomarker in Nonsmall Cell Lung Cancer and Suppresses Cell Growth With the Involvement of a Target PIK3R1

MicroRNAs are a class of noncoding RNAs that can be involved in the regulation of gene expression in cancers, including lung cancer. Our previous research has shown that miR-486-5p is one of the most downregulated microRNAs in tissue and serum samples of lung cancer as a good diagnostic biomarker. The objective of this study is to investigate the roles of miR-486-5p in the progression of lung cancer. In this study, miR-486-5p was further validated to be significantly downregulated in additional nonsmall cell lung cancer (NSCLC) tissue, serum, and cell samples by quantitative reverse transcription-polymerase chain reaction (RT-PCR), and the expression level of miR-486-5p was significantly associated with clinical phenotype of NSCLC. The PIK3R1 gene was confirmed to be a direct target of miR-486-5p by dual-luciferase reporter assay, and the expression level of miR-486-5p was inversely correlated with that of PIK3R1 in tumor tissues (r = −0.774, p < 0.01). Overexpressed miR-486-5p effectively inhibited cell proliferation and invasion and successfully induced apoptosis in vitro. PIK3R1 was involved in the suppression of miR-486-5p on cell growth. It can be concluded that miR-486-5p may act as a tumor suppressor contributing to the progression of NSCLC, and miR-486-5p would be a diagnostic and prognostic biomarker and a potential therapeutic target for lung cancer.

Expression of miR-486-5p and its significance in lung squamous cell carcinoma

Lung squamous cell carcinoma (LUSC) is one of the main histological types of lung cancer with high mortality. The role of microRNA-486-5p in LUSC remains unclear. In the current study, the aim was to explore miR-486-5p expression and its role in LUSC. The miR-486-5p expression was significantly low-expressed in patients with LUSC from The Cancer Genome Atlas database, which was further confirmed in the Gene Expression Omnibus database, patients' tissues, different cell lines by quantitative real-time polymerase chain reaction, and the high-throughput gene sequencing data of lung tissues of mice after a long-term B(a)P exposure. The meta-analysis was performed to evaluate the expression and diagnosis power of miR-486-5p (standard mean difference = -2.25; 95% confidence interval: -3.47 to -1.03; P = 0.0003; area under curve = 0.9082). Functional enrichment analysis revealed the potential function of miR-486-5p in LUSC using gene set enrichment analysis and clusterProfiler package in R software. At last, the hub genes (PTEN, TEK, PIK3R1, PPM1B, SMAD2, and SPTA1) of miR-486-5p were verified. In conclusion, miR-486-5p may be a LUSC antioncogene, playing an important role to serve as a biomarker in LUSC.

Serum miR-210-3p as a Potential Noninvasive Biomarker of Lung Adenocarcinoma: A Preliminary Study

Background: Development of noninvasive biomarkers could potentially contribute to extending the 5-year overall survival rate of nonsmall cell lung cancer (NSCLC) patients. Circulating microRNAs (miRNAs), due to their high stability, have the potential to become valuable cancer biomarkers. Methods: Using reverse transcription-quantitative polymerase chain reaction and testing three methods for data normalization, the expression levels of six miRNAs were evaluated in serum samples obtained from 50 NSCLC patients. Subsequently, the clinical significance of the tested miRNAs was determined. Results: Significant downregulation of miR-21-5p, miR-30a-5p, and miR-126-3p and upregulation of miR-210-3p and miR-486-5p in serum samples of NSCLC patients were identified in comparison to healthy controls. miR-205-5p appeared to be undetectable in all tested samples. Furthermore, miR-210-3p was differentially expressed between two subtypes of NSCLC. Receiver operating characteristic analysis for miR-210-3p revealed the area under the curve of 0.842 (95% confidence interval, 0.72-0.96; p = 0.0003) and demonstrated that miR-210-3p displayed considerable accuracy in discriminating between lung adenocarcinoma (AC) patients and healthy controls. Conclusions: Findings from this preliminary study indicate that five of six tested miRNAs were deregulated in the serum of NSCLC patients. Moreover, miR-210-3p appears to be a promising biomarker for diagnosis of lung AC.

MiR-181a, a new regulator of TGF-β signaling, can promote cell migration and proliferation in gastric cancer

Transforming growth factor-beta (TGF-β) signaling pathway plays pivotal roles in various types of cancer. TGF-β receptor 2 (TGFβR2) contains a kinase domain that phosphorylates and activates the downstream of the TGF-β signaling pathway. Our previous microarray analysis revealed marked changes in miR-181a expression in gastric cancers, and the bioinformatics analysis suggested that miR-181a negatively regulated TGFβR2. In order to verify the effect of miR-181a on TGFβR2 and clarify the influence of miR-181a on the migration and proliferation of gastric cancer, studies in gastric cancer cell lines and xenograft mouse models were carried out. We found that a reduced expression of TGFβR2 and an increased expression miR-181a in gastric cancer tissues compared to adjacent noncancerous tissues. A luciferase reporter assay confirmed that TGFβR2 was a target of miR-181a. In addition, we found that miR-181a mimics, which increased the level of miR-181a, downregulated the expression of TGFβR2 in the gastric cancer cell line SGC-7901. Moreover, both the overexpression of miR-181a and the downregulation of TGFβR2 promoted the migration and proliferation of SGC-7901 cells. Conversely, SGC-7901 cell migration and proliferation were inhibited by the downregulation of miR-181a and the overexpression of TGFβR2. Furthermore, the increased expression of miR-181a and the decreased expression of TGFβR2 also enhanced the tumor growth in mice bearing gastric cancer. Our results herein indicated that miR-181a promoted the migration and proliferation of gastric cancer cells by downregulating TGFβR2 at the posttranscriptional level. The present study suggests that miR-181a is a novel negative regulator of TGFβR2 in the TGF-β signaling pathway and thus represents a potential new therapeutic target for gastric cancer.

miR-181a/b therapy in lung cancer: reality or myth?

Despite substantial progress in oncology, lung cancer remains the number one malignancy in terms of both incidence and mortality rates, and there thus remains an urgent need for new therapeutic alternatives. MicroRNA (miRNA) have an important role in cancer initiation and progression due to their capacity to interfere with transcriptional signaling and regulate key cellular processes. miR-181a and miR-181b (miR-181a/b), which are located on chromosomes 1 and 9, are pathologically expressed in the tumor tissue and plasma of patients diagnosed with lung cancer. The miR-181a/b regulatory mechanisms are sophisticated and are directly related to different target genes. In recent years, an ever-increasing number of studies have focused on the biological relevance of miR-181a/b in key cellular processes. In this paper, we aim to discuss the challenging experimental data related to miR-181a/b and their potential use for the development of new therapeutic approaches in lung cancer. We will further present the ongoing issues regarding the regulation of their multiple target genes, and their potential use as biomarkers and therapeutic targets in this deadly malignancy.

miR-181b-5p suppresses starvation-induced cardiomyocyte autophagy by targeting Hspa5

This study aimed to investigate the role of microRNA-181b-5p (miR-181b-5p) in starvation-induced cardiomyocyte autophagy by targeting heat shock protein family A member 5 (Hspa5). For this purpose, H9c2 cardiomyocytes and neonatal rat ventricular myocytes (NRVMs) were glucose-starved in Earle's Balanced Salt Solution (EBSS) for different periods of time (0, 2, 4, 6 and 8 h). RT-qPCR analysis was performed to examine the expression of miR-181b-5p in the different groups. Immunofluorescence was performed to detect the expression of LC3. In addition, the H9c2 cardiomyo-cytes and NRVMs were transfected with miR-181b-5p mimic, miR-181b-5p inhibitor, siHspa5 or their respective controls. An MTT assay was performed to measure cell proliferation in the different groups. Western blot analysis was performed to determine the expression of Beclin-1, Hspa5, phosphorylated phosphoinositide 3-kinase PI3K (p-PI3K), phosphorylated Akt (p-Akt), phosphorylated mammalian target of rapamycin (p-mTOR), Bcl-2, Bax and cleaved caspase-3. Flow cytometry was performed to assess cell apoptosis. A luciferase reporter assay was performed to determine whether Hspa5 is a direct target of miR-181b-5p. The results revealed that the down-regulation of miR-181b-5p promoted cell autophagy in the cardiomyocytes. Moreover, miR-181b-5p negatively regulated Beclin-1 and Hspa5. Beclin-1 is a well-known autophagy- and apoptosis-related protein. In addition, cell apoptosis was attenuated by the decreased expression of miR-181b-5p in the cardiomyocytes. Bcl-2 prevented apoptosis and autophagy by binding to Bax and Bcl-2, respectively. The upregulation of miR-181b-5p inhibited autophagy and promoted apoptosis via Hspa5. miR-181b-5p inhibition promoted p-mTOR, p-Akt and p-PI3K expression via Hspa5. The results of luciferase reporter assay also confirmed that Hspa5 is a direct target of miR-181b-5p. On the whole, the findings of this study suggest that miR-181b-5p contributes to starvation-induced autophagy and apoptosis in cardiomyocytes by directly targeting Hspa5 via the PI3K/Akt/mTOR signaling pathway.

Correlation of Expression Levels of Micro Ribonucleic Ccid-10b (miR-10b) and Micro Ribonucleic Acid-181b (miR-181b) with Gastric Cancer and Its Diagnostic Significance

Background

The aim of this study was to explore the expression levels of micro ribonucleic acid-10b (miR-10b) and micro ribonucleic acid-181b (miR-181b) in gastric cancer tissues, as well as their application value in clinical diagnosis and treatment.

Material/Methods

A total of 120 patients with gastric cancer who were diagnosed and treated in the Department of Gastroenterology of our hospital were enrolled in this study. The gastric cancer tissues and paracancerous tissues were collected for measuring the expression of miR-10b and miR-181b by in situ hybridization and reverse transcription-polymerase chain reaction (RT-PCR). The 5-year survival rate was also analyzed.

Results

The expressions of miR-10b and miR-181b in gastric cancer tissues were both upregulated and were significantly higher than those in the paracancerous tissues (p<0.05). In addition, the expressions of miR-10b and miR-181b in gastric cancer tissues were correlated with tumor size, degree of pathological differentiation, depth of infiltration, tumor node metastasis (TNM) staging, and lymph node metastasis, as well as local lymph node and distant metastasis (p<0.05). For patients in stage II and III, the expressions of miR-10b and miR-181b were significantly correlated with the 5-year survival rate.

Conclusions

The high expressions of miR-10b and miR-181b are significantly correlated with poor prognosis in stage II and III patients with gastric cancer, suggesting that their expressions might be criteria for evaluating the prognosis of gastric cancer.

[MicroRNA and Lung Cancer: A Mini Review]

MicroRNAs (miRNAs) a class of non-coding RNAs about 22 nt in size that are found in a wide range of organisms from plants, viruses to humans. MicroRNA has a wide range of biological functions. It can recruit related RNA enzymes and lead to mRNA degradation after binding to mRNA specificity, thus blocking the expression of protein encoding genes and then affecting their biological functions. In recent years, microRNA has been found to be closely related to the biological behaviors, such as the occurrence, development, invasion and metastasis of multiple human malignant carcinomas, and play a regulatory role in the above biological phenotypes. Lung cancer is the highest incidence of malignancy. The exact molecular mechanism of its occurrence and development has not been fully elucidated. Previous studies have shown that microRNA plays an important role in lung tumor suppressor gene inactivation, oncogene activation and epigenetics. At the same time, there are also reports that there is a significant difference in the expression of microRNA in patients with lung cancer and benign lung diseases. This differential expression provides a basis for the feasibility of microRNA as a diagnostic and pre biological marker for lung cancer.
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MicroRNA-181 Functions as an Antioncogene and Mediates NF-κB Pathway by Targeting RTKN2 in Ovarian Cancers

MicroRNA (miR)-181 has been reported to participate in carcinogenesis and tumor progression in several malignant cancers, but its expression and biological functions in ovarian cancer have remained largely unclarified. Here, we first measured miR-181 expression in clinical ovarian cancers and found the expression levels of miR-181 were significantly lower in ovarian cancer tissues than that in adjacent tissues. Next, we screened and identified a direct miR-181 target, Rhotekin2 (RTKN2). A correlation between miR-181 and RTKN2 expression was also confirmed in clinical samples of ovarian cancers. Upregulation of miR-181 would specifically and markedly suppress RTKN2 expression. The miR-181-overexpressing subclones showed significant cell growth inhibition by cell apoptosis induction and significant impairment of cell invasiveness in SKOV3 and HO8910 ovarian cancer cells. To identify the mechanisms, we investigated the NF-κB pathway and found that nuclear factor-kappa B (NF-κB), B-cell lymphoma-2 (Bcl-2), and vascular endothelial growth factor (VEGF) were suppressed, whereas IκBα was promoted in miR-181-overexpressing cells. These findings indicate that miR-181 functions as a tumor suppressor and plays a substantial role in inhibiting the tumorigenesis and reversing the metastasis of ovarian cancer through RTKN2-NF-κB signaling pathway in vitro. Taken together, we believe that miR-181 may be a promising therapeutic target for treating malignant ovarian cancers.

MicroRNA Expression Profiling in Adrenal Myelolipoma

INTRODUCTION

Adrenal myelolipoma (AML) is the second most common and invariably benign primary adrenal neoplasm. Due to the variable proportion of fat and hematopoietic elements and its often large size, it can cause differential diagnostic problems. Several reports confirmed the utility of miRNAs in the diagnosis of tumors, but miRNA expression in AML has not yet been investigated.

MATERIALS AND METHODS

Next-generation sequencing (NGS) was performed on 30 formalin-fixed, paraffin-embedded (FFPE) archived tissue samples [10 each of AML, adrenocortical adenoma (ACA), and adrenocortical carcinoma (ACC)]. Validation was performed by real-time quantitative reverse transcription polymerase chain reaction on a cohort containing 41 further FFPE samples (15 AML, 14 ACA, and 12 ACC samples). Circulating miRNA counterparts of significantly differentially expressed tissue miRNAs were studied in 33 plasma samples (11 each of ACA, ACC, and AML).

RESULTS

By NGS, 256 significantly differentially expressed miRNAs were discovered, and 8 of these were chosen for validation. Significant overexpression of hsa-miR-451a, hsa-miR-486-5p, hsa-miR-363-3p, and hsa-miR-150-5p was confirmed in AML relative to ACA and ACC. hsa-miR-184, hsa-miR-483-5p, and hsa-miR-183-5p were significantly overexpressed in ACC relative to ACA but not to AML. Circulating hsa-miR-451a and hsa-miR-363-3p were significantly overexpressed in AML, whereas circulating hsa-miR-483-5p and hsa-miR-483-3p were only significantly overexpressed in ACC vs ACA.

CONCLUSIONS

We have found significantly differentially expressed miRNAs in AML and adrenocortical tumors. Circulating hsa-miR-451a might be a promising minimally invasive biomarker of AML. The lack of significantly different expression of hsa-miR-483-3p and hsa-miR-483-5p between AML and ACC might limit their applicability as diagnostic miRNA markers for ACC.

miR-181b inhibits chemoresistance in cisplatin-resistant H446 small cell lung cancer cells by targeting Bcl-2

INTRODUCTION

MicroRNAs (miRNAs) are a group of small non-coding RNAs that affect multiple aspects of tumor biology including chemo resistance. miR-181b has been reported to modulate multidrug resistance in non-small cell lung cancer cells. This study was undertaken to determine the role of miR-181b in chemo resistance of small cell lung cancer cells.

MATERIAL AND METHODS

This study was undertaken to determine the role of miR-181b in chemoresistance of small cell lung cancer cells with use of qRt-PCR, WB, bioinformatics analysis, and double luciferase reporter system.

RESULTS

Our data showed that miR-181b was significantly downregulated in cisplatin-resistant H446 small cell lung cancer cells, compared to parental cells, compared to parental cells. Ectopic expression of miR-181b inhibited cell proliferation and invasion in cisplatin-resistant H446 cells (p = 0.023). Moreover, overexpression of miR-181b increased the susceptibility of cisplatin-resistant H446 cells to cisplatin. Mechanistic investigations demonstrated that miR-181b inhibited B-cell lymphoma-2 (Bcl-2) expression by binding to the 3'-untranslated region. Overexpression of Bcl-2 reversed miR-181b-mediated chemo sensitization, which is accompanied by a reduced apoptotic response.

CONCLUSIONS

Taken together, this work demonstrated that miR-181b might have the ability to overcome chemo resistance of small cell lung cancer cells, and restoration of this miRNA may represent a potential therapeutic strategy for improving chemo sensitivity in small cell lung cancer.

Microarray profiles reveal that circular RNA hsa_circ_0007385 functions as an oncogene in non-small cell lung cancer tumorigenesis

OBJECTIVE

Circular RNAs (circRNAs) are a novel class of non-protein-coding RNA. Emerging evidence indicates that circRNAs participate in the regulation of many pathophysiological processes. This study aims to explore the expression profiles and pathological effects of circRNAs in non-small cell lung cancer (NSCLC).

METHODS

Human circRNAs microarray analysis was performed to screen the expression profile of circRNAs in NSCLC tissue. Expressions of circRNA and miRNA in NSCLC tissues and cells were quantified by qRTPCR. Functional experiments were performed to investigate the biological functions of circRNA, including CCK-8 assay, colony formation assay, transwell assay and xenograft in vivo assay.

RESULTS

Human circRNAs microarray revealed a total 957 abnormally expressed circRNAs (> twofold, P < 0.05) in NSCLC tissue compared with adjacent normal tissue. In further studies, hsa_circ_0007385 was significantly up regulated in NSCLC tissue and cells. In vitro experiments with hsa_circ_0007385 knockdown resulted in significant suppression of the proliferation, migration and invasion of NSCLC cells. In vivo xenograft assay using hsa_circ_0007385 knockdown, significantly reduced tumor growth. Bioinformatics analysis and luciferase reporter assay verified the potential target miR-181, suggesting a possible regulatory pathway for hsa_circ_0007385.

CONCLUSION

In summary, results suggest hsa_circ_0007385 plays a role in NSCLC tumorigenesis, providing a potential therapeutic target for NSCLC.

miR-181a targets GATA6 to inhibit the progression of human laryngeal squamous cell carcinoma

AIM

We sought to determine the function of miR-181a/GATA6 pathway in the progression of laryngeal squamous cell carcinoma (LSCC).

MATERIALS & METHODS

The expression of miR-181a and GATA6 were detected using quantitative real-time-PCR and western blotting in 127 LSCC samples and 32 corresponding control mucosa tissues. Cell death, migration and apoptosis were measured in Hep-2 cells using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT), Transwell migration assay and apoptosis assay, respectively. The prognosis was determined by the follow-up, univariate analysis and multivariate analysis.

RESULTS

We observed decreased miR-181a levels and increased GATA6 expression in LSCC samples compared with control mucosa tissues. Transfection of miR-181a decreased GATA6 expression, suppressed migration and promoted apoptosis in Hep-2 cells. Furthermore, silencing GATA6 suppressed cell migration and promoted apoptosis in Hep-2 cells. Notably, patients with high miR-181a levels had a longer life span.

CONCLUSION

MiR-181a inhibits LSCC progression via suppressing GATA6 expression. MiR-181a is an independent prognostic factor in LSCC patients.

Differential microRNA expression profiles in tamoxifen-resistant human breast cancer cell lines induced by two methods

Tamoxifen (TAM) resistance has become a severe problem for endocrine therapy of breast cancer. The present study investigated the association between microRNA (miRNA) expression and TAM resistance in breast cancer. The TAM-resistant breast cancer MCF-7C and MCF-7T cell lines were established using the human breast cancer cell line MCF-7 as the parental cell line and 4-hydroxytamoxifen (OHT) as the screening drug in vitro. The MCF-7C cell line was established by dose stepwise induction beginning with a low concentration of OHT; the MCF-7T cell line was established by temporal stepwise induction beginning with a high concentration of OHT. Differential miRNA expression profiles between TAM-sensitive (MCF-7) and TAM-resistant (MCF-7C and MCF-7T) breast cancer cell lines were detected and analyzed using RNA sequencing technology. The results of western blot analysis indicated that the level of ERα protein expression in drug-resistant cells was significantly increased. A total of 1,646 miRNAs were detected in all samples, including 1,376 known miRNAs and 270 predicted miRNAs. There were 118 miRNAs expressed at significantly different levels between MCF-7C and MCF-7 cells (P<0.05); among them, 67 miRNAs were upregulated (P<0.05) and 51 miRNA were downregulated (P<0.05). There were 42 miRNAs expressed at significantly different levels between MCF-7T and MCF-7 (P<0.05); among them, 23 miRNAs were upregulated (P<0.05) and 19 miRNAs were downregulated (P<0.05). There were 126 miRNAs with significant differences between MCF-7C and MCF-7T (P<0.05); among them, 76 miRNAs were upregulated (P<0.05) and 50 miRNAs were downregulated. On the basis of the results of the present study, we hypothesize that miR-21, miR-146a, miR-148a, miR-34a and miR-27a may serve important roles in mediating TAM resistance in breast cancer, and have potential as therapeutic targets for TAM-resistant breast cancer.

Diagnosis value of aberrantly expressed microRNA profiles in lung squamous cell carcinoma: a study based on the Cancer Genome Atlas

Background

Lung cancer is considered as one of the most frequent and deadly cancers with high mortality all around the world. It is critical to find new biomarkers for early diagnosis of lung cancer, especially lung squamous cell carcinoma (LUSC). The Cancer Genome Atlas (TCGA) is a database which provides both cancer and clinical information. This study is a comprehensive analysis of a novel diagnostic biomarker for LUSC, based on TCGA.

Methods and Results

The present study investigated LUSC-specific key microRNAs (miRNAs) from large-scale samples in TCGA. According to exclusion criteria and inclusion criteria, the expression profiles of miRNAs with related clinical information of 332 LUSC patients were obtained. Most aberrantly expressed miRNAs were identified between tumor and normal samples. Forty-two LUSC-specific intersection miRNAs (fold change >2, p < 0.05) were obtained by an integrative computational method, among them six miRNAs were found to be aberrantly expressed concerning characteristics of patients (gender, lymphatic metastasis, patient outcome assessment) through Student t-test. Five miRNAs correlated with overall survival (log-rank p < 0.05) were obtained through the univariate Cox proportional hazards regression model and Mantel–Haenszel test. Then, five miRNAs were randomly selected to validate the expression in 47 LUSC patient tissues using quantitative real-time polymerase chain reaction. The results showed that the test findings were consistent with the TCGA findings. Also, the diagnostic value of the specific key miRNAs was determined by areas under receiver operating characteristic curves. Finally, 577 interaction mRNAs as the targets of 42 LUSC-specific intersection miRNAs were selected for further bioinformatics analysis.

Conclusion

This study indicates that this novel microRNA expression signature may be a useful biomarker of the diagnosis for LUSC patients, based on bioinformatics analysis.

miR-491 Inhibits Osteosarcoma Lung Metastasis and Chemoresistance by Targeting αB-crystallin

Dysregulated microRNAs (miRNAs) play an important role in osteosarcoma (OS) progression. In the present study, we investigate the clinical significance of serum miR-491 level and the potential role of miR-491 in OS lung metastasis and chemoresistance. Clinical data show that the level of miR-491 was decreased in serum from OS patients compared with healthy control subjects, and that a decreased serum miR-491 level is correlated with increased metastasis, poor chemoresponse, and lower survival rate in OS patients. In vitro and in vivo experiments show that overexpression of miR-491 suppresses OS cell lung metastasis, whereas it enhances cisplatin (CDDP)-induced tumor growth inhibition and apoptosis. In contrast, inhibition of miR-491 stimulates OS cell lung metastasis and suppresses CDDP-induced tumor growth inhibition and apoptosis. Furthermore, we demonstrate that miR-491 exerts its role by directly targeting αB-crystallin (CRYAB) in OS. Our findings suggest that serum level of miR-491 has potential as a biomarker for predicting OS progression and prognosis of OS patients. Additionally, restoration of miR-491 may be a novel strategy for inhibiting OS lung metastasis and overcoming OS cell resistance to chemotherapy.

No Significant Difference between Plasma miRNAs and Plasma-Derived Exosomal miRNAs from Healthy People

Background

MicroRNAs (miRNAs) are small noncoding RNAs that are involved in many biological regulation processes. Studies have reported that miRNAs are enriched in human plasma and plasma-derived exosome as novel diagnostic biomarkers. The aim of this study was to determine whether the miRNA expression levels are different between plasma and plasma-derived exosome.

Methods

We sequenced and quantified the miRNAs in plasma and exosome from healthy blood samples and validated three miRNAs in the two groups of lung cancer samples by qRT-PCR.

Results

The sequencing results showed that only several of miRNAs were differential, while the qRT-PCR further validated that most of them did not have the consistent differences. However, the levels of two upregulated miRNAs (miR-181b-5p and miR-21-5p) in lung cancer were significantly higher in exosomes than plasma.

Conclusions

To the best of our knowledge, this study is the first to compare the expression levels of miRNAs between plasma and exosome in healthy blood samples. Our data suggested that the miRNA levels were similar in the two parts of the healthy people, whereas the two onco-miRNAs were significantly enriched in the exosome of lung cancer patients.