miR-186-5p targeting SIX1 inhibits cisplatin resistance in non-small-cell lung cancer cells (NSCLCs)

Sufentanil Suppresses Cell Carcinogenesis Via Targeting miR-186-5p/HMGB1 Axis and Wnt/β-Catenin Pathway in Non-Small-Cell Lung Cancer

Sufentanil is a common opioid anesthetic agent, which exerts anti-cancer properties in several cancer types. However, its action mechanisms in non-small cell lung cancer (NSCLC) are unclear. Therefore, the present study investigated the pharmacological effect of sufentanil on miRNAs in NSCLC treatment. In this study, after treatment with sufentanil, the proliferation, migration, invasion and apoptosis of A549 and H1299 NSCLC cell lines were measured by cell counting kit-8 (CCK-8) assay, colony formation assay, transwell assays and flow cytometry. Quantitative real time polymerase chain reaction (qRT-PCR) was utilized to detect the expression of miR-186-5p and high mobility group box-1 (HMGB1), and their interaction was analyzed using luciferase reporter assay. The proteins of HMGB1, and apoptosis- and Wnt/β-catenin pathway-related factors were detected by western blot. It was demonstrated that sufentanil significantly upregulated miR‑186‑5p to restrict NSCLC cell proliferation, migration, invasion, and boost apoptosis in vitro. Mechanically, miR-186-5p interacted with HMGB1 and negatively regulated HMGB1 in NSCLC cells. Furthermore, rescue assay showed that sufentanil exerted antitumor activities by upregulating miR-186-5p, which targeted HMGB1 and restrained Wnt/β-catenin signal pathway in NSCLC cells. In conclusion, these results suggested that sufentanil disrupts the oncogenicity of NSCLC cells by regulating miR-186-5p/HMGB1/β-catenin axis, providing a promising implication for the anti-oncogenic effect of sufentanil.

Hsa_circ_0119412 Contributes to Development of Retinoblastoma by Targeting miR-186-5p/ELK4 Axis

Increasing evidences indicate the crucial role of circRNAs in tumorigenesis, but little is understood about their molecular mechanism in retinoblastoma (RB). This paper was designed for exploring the circ_0119412 function in cases with RB and the potential mechanism. RT-qPCR was utilized to ascertain circ_0119412 and miR-186-5p levels in RB tissues and cells, and western blotting was used to quantify ELK4 in RB cells. In addition, CCK-8 and scratch assays were carried out for evaluation of cell proliferation and migration, respectively. Apoptosis-related proteins levels (Bax and Bcl-2) were measure by western blotting. Tumor growth in vivo was detected utilizing xenograft tumor experiment. The targeting relationship between circ_0119412, miR-186-5p, and ELK4 was validated using a dual-luciferase reporter assay and an RNA immunoprecipitation (RIP) assay. In RB tissues and cells, Circ_0119412 and ELK4 expression were upregulated, while miR-186-5p expression was downregulated. In vitro assay revealed that downregulating circ_0119412 accelerated the cell apoptosis of RB cells and slowed down their migration and proliferation, and the in vivo assay indicated that circ_0119412 downregulation reduced the weight and volume of tumor in nude mice. In addition, miR-186-5p interference promoted the malignant behavior of RB cells, while ELK4 silencing showed an opposite trend. Mechanically, circ_0119412 can promote RB malignant phenotypes via miR-186-5p/ELK4 axis. Circ_0119412 was found to be upregulated in RB, and could accelerate the progression of RB via the miR-186-5p/ELK4 axis, indicating circ_0119412 may serve a promising clinical therapeutic target of RB.

miR-186-ANXA9 signaling inhibits tumorigenesis in breast cancer

Breast cancer (BC) ranks as the highest incidence among cancer types in women all over the world. MicroRNAs (miRNAs) are a class of short endogenous non-coding RNA in cells mostly functioning to silence the target mRNAs. In the current study, a miRNA screening analysis identified miR-186-5p to be downregulated in human breast cancer tumors. Functional studies in vitro demonstrated that overexpression of miR-186-5p inhibited cellular proliferation and induced cell apoptosis in multiple breast cancer cell lines including MDA-MB-231, MCF-7, and BT549 cells. Transplantation of the miR-186-5p-overexpressing MDA-MB-231 cells into nude mice significantly inhibited mammary tumor growth in vivo. Sequence blast analysis predicted annexin A9 (ANXA9) as a target gene of miR-186-5p, which was validated by luciferase reporter assay, QRT-PCR analysis, and western blot. Additional gene expression analysis of clinical tumor samples indicated a negative correlation between miR-186-5p and ANXA9 in human breast cancer. Knockdown of ANXA9 mimicked the phenotype of miR-186-5p overexpression. Reintroduction of ANXA9 back rescued the miR-186-5p-induced cell apoptosis. In addition, miR-186-5p decreased the expression of Bcl-2 and increased the expression of p53, suggesting a mechanism regulating miR-186-5p-induced cellular apoptosis. In summary, our study is the first to demonstrate miR-186-5p-ANXA9 signaling in suppressing human breast cancer. It provided a potential therapeutic target in breast cancer.

circ_0000376 knockdown suppresses non-small cell lung cancer cell tumor properties by the miR-545-3p/PDPK1 pathway

Non-small cell lung cancer (NSCLC) accounts for 80% of total lung cancers, which are the main killer of cancer-related death worldwide. Circular RNA (circRNA) has been found to modulate NSCLC development. However, the role of circ_0000376 in NSCLC development has been underreported. The present work showed that circ_0000376 and 3-phos-phoinositide-dependent protein kinase-1 (PDPK1) expression were dramatically increased, but miR-545-3p was decreased in NSCLC tissues and cells. circ_0000376 expression was closely associated with lymph node metastasis, tumor-node-metastasis stage, and tumor size of NSCLC patients. circ_0000376 knockdown repressed NSCLC cell proliferation, migration, invasion, and glutaminolysis but induced cell apoptosis. Additionally, miR-545-3p bound to circ_0000376, and circ_0000376 regulated cell phenotypes by associating with miR-545-3p. MiR-545-3p also participated in NSCLC cell proliferation, migration, invasion, apoptosis, and glutaminolysis by targeting PDPK1. Further, circ_0000376 absence repressed tumor formation in vivo. Collectively, circ_0000376 regulated NSCLC cell tumor properties by the miR-545-3p/PDPK1 axis, suggesting that circ_0000376 could be employed as a therapeutic target for NSCLC.

Hypoxia-induced downregulation of microRNA-186-5p in endothelial cells promotes non-small cell lung cancer angiogenesis by upregulating protein kinase C alpha

The tumor microenvironment stimulates the angiogenic activity of endothelial cells (ECs) to facilitate tumor vascularization, growth, and metastasis. The involvement of microRNA-186-5p (miR-186) in regulating the aberrant activity of tumor-associated ECs has so far not been clarified. In the present study, we demonstrated that miR-186 is significantly downregulated in ECs microdissected from human non-small cell lung cancer (NSCLC) tissues compared with matched non-malignant lung tissues. In vitro analyses of primary human dermal microvascular ECs (HDMECs) exposed to different stimuli indicated that this miR-186 downregulation is triggered by hypoxia via activation of hypoxia-inducible factor 1 alpha (HIF1α). Transfection of HDMECs with miR-186 mimic (miR-186m) significantly inhibited their proliferation, migration, tube formation, and spheroid sprouting. In contrast, miR-186 inhibitor (miR-186i) exerted pro-angiogenic effects. In vivo, endothelial miR-186 overexpression inhibited the vascularization of Matrigel plugs and the initial growth of tumors composed of NSCLC cells (NCI-H460) and HDMECs. Mechanistic analyses revealed that the gene encoding for protein kinase C alpha (PKCα) is a bona fide target of miR-186. Activation of this kinase significantly reversed the miR-186m-repressed angiogenic activity of HDMECs. These findings indicate that downregulation of miR-186 in ECs mediates hypoxia-stimulated NSCLC angiogenesis by upregulating PKCα.

miR-221-5p and miR-186-5p Are the Critical Bladder Cancer Derived Exosomal miRNAs in Natural Killer Cell Dysfunction

Bladder cancer (BC) is the tenth most commonly diagnosed cancer worldwide, and its carcinogenesis mechanism has not been fully elucidated. BC is able to induce natural killer (NK) cell dysfunction and escape immune surveillance. The present study found that exosomes derived from the urinary bladder cancer cell line (T24 cell) contribute in generating NK cell dysfunction by impairing viability, and inhibiting the cytotoxicity of the NK cell on target cells. Meanwhile, T24 cell-derived exosomes inhibited the expression of the important functional receptors NKG2D, NKp30, and CD226 on NK cells as well as the secretion of perforin and granzyme-B. The critical miRNAs with high expression in T24 cell-derived exosomes were identified using high-throughput sequencing. Furthermore, following dual-luciferase reporter assay and transfection experiments, miR-221-5p and miR-186-5p were confirmed as interfering with the stability of the mRNAs of DAP10, CD96, and the perforin gene in NK cells and may be potential targets used in the therapy for BC.

MicroRNAs and Drug Resistance in Non-Small Cell Lung Cancer: Where Are We Now and Where Are We Going

Lung cancer is the leading cause of cancer-related mortality in the world. The development of drug resistance represents a major challenge for the clinical management of patients. In the last years, microRNAs have emerged as critical modulators of anticancer therapy response. Here, we make a critical appraisal of the literature available on the role of miRNAs in the regulation of drug resistance in non-small cell lung cancer (NSCLC). We performed a comprehensive annotation of miRNAs expression profiles in chemoresistant versus sensitive NSCLC, of the drug resistance mechanisms tuned up by miRNAs, and of the relative experimental evidence in support of these. Furthermore, we described the pros and cons of experimental approaches used to investigate miRNAs in the context of therapeutic resistance, to highlight potential limitations which should be overcome to translate experimental evidence into practice ultimately improving NSCLC therapy.

METTL3/LINC00662/miR-186-5p feedback loop regulates docetaxel resistance in triple negative breast cancer

Insight into the mechanism of docetaxel resistance in breast cancer may help to improve prognosis. We aimed to investigate the role of N6-methyladenosine (m6A) and the METTL3/LINC00662/miR-186-5p pathway in regulating docetaxel resistance in triple negative breast cancer (TNBC). We have recruited 193 pathologically diagnosed TNBC patients from 2016 to 2017 in our hospital. Quantitative real-time PCR was used to evaluate the expression of LINC00662 and miR-186-5p both in vivo and in vitro. CCK8 tests were used to assess cell viability. ELISA was used for protein expression evaluation. Dual luciferase reporter gene assay and RNA pull-down were used to evaluate the interaction between LINC00662 and miR-186-5p. m6A levels were enhanced in breast cancer tissues and cells. LINC00662, miR-186-5p and METTL3 were differentially expressed in vivo, and METTL3 expression was associated with LINC00662 and miR-186-5p expression. LINC00662 and miR-186-5p were differentially expressed in vitro; LINC00662 promoted cell viability and decreased the apoptosis rate, whereas miR-186-5p inhibited cell viability and increased the apoptosis rate. Furthermore, we found that METTL3 regulated m6A levels in docetaxel-resistant breast cancer cells by regulating the expression of LINC00662. Moreover, LINC00662 and miR-186-5p regulated the cell viability rate of docetaxel-resistant breast cancer cells. Further experiments showed that LINC00662 directly interacted with miR-186-5p to exert biological functions; besides miR-186-5p could regulate the expression of METTL3. METTL3 promotes m6A levels and docetaxel resistance in breast cancer by regulating the expression of LINC00662 and miR-186-5p; more experiments are needed to clarify the role of m6A regulation in drug resistance.

Ursolic Acid Enhances Cytotoxicity of Doxorubicin-Resistant Triple-Negative Breast Cancer Cells via ZEB1-AS1/miR-186-5p/ABCC1 Axis

Background: Triple-negative breast cancer (TNBC) is the most serious subtype of breast cancer (BC) and has been a great health threat to females. Although chemotherapeutic agent contributes a lot to TNBC treatment, drug resistance has been a great obstacle for chemotherapies. Ursolic acid (UA), a pentacyclic triterpenoid compound, was reported to reverse paclitaxel resistance in BC. However, whether UA could affect the resistance of TNBC cells to other drugs such as doxorubicin (DOX) remains to be discovered. Materials and Methods: MTT assay, EdU assay, colony formation assay, and flow cytometry analysis were implemented to detect the viability, proliferation, and apoptosis of DOX-resistant MDA-MB-468 and MDA-MB-436 cells with or without UA treatment. Mechanism assays including RIP, RNA pull-down, and luciferase reporter assays verified the interaction between RNAs. Results: UA treatment hindered the growth and mitigated the DOX resistance of DOX-resistant MDA-MB-468 and MDA-MB-436 cells. Mechanistically, multidrug resistance-associated protein 1 (ABCC1) expression was downregulated by UA treatment. MiR-186-5p was verified to target ABCC1. Further, UA-inhibited ZEB1-AS1 (zinc finger E-box binding homeobox 1 antisense RNA 1) was verified as a competitive endogenous RNA (ceRNA) to upregulate ABCC1 through sponging miR-186-5p. Importantly, UA treatment impaired the malignant phenotypes of DOX-resistant MDA-MB-468 and MDA-MB-436 cells through ZEB1-AS1/ABCC1 axis. Conclusion: UA promotes TNBC cell sensitivity to DOX through inactivating ZEB1-AS1/miR-186-5p/ABCC1 signaling.

Non-coding RNA in cancer drug resistance: Underlying mechanisms and clinical applications

Cancer is one of the most frequently diagnosed malignant diseases worldwide, posing a serious, long-term threat to patients’ health and life. Systemic chemotherapy remains the first-line therapeutic approach for recurrent or metastatic cancer patients after surgery, with the potential to effectively extend patient survival. However, the development of drug resistance seriously limits the clinical efficiency of chemotherapy and ultimately results in treatment failure and patient death. A large number of studies have shown that non-coding RNAs (ncRNAs), particularly microRNAs, long non-coding RNAs, and circular RNAs, are widely involved in the regulation of cancer drug resistance. Their dysregulation contributes to the development of cancer drug resistance by modulating the expression of specific target genes involved in cellular apoptosis, autophagy, drug efflux, epithelial-to-mesenchymal transition (EMT), and cancer stem cells (CSCs). Moreover, some ncRNAs also possess great potential as efficient, specific biomarkers in diagnosis and prognosis as well as therapeutic targets in cancer patients. In this review, we summarize the recent findings on the emerging role and underlying mechanisms of ncRNAs involved in cancer drug resistance and focus on their clinical applications as biomarkers and therapeutic targets in cancer treatment. This information will be of great benefit to early diagnosis and prognostic assessments of cancer as well as the development of ncRNA-based therapeutic strategies for cancer patients.

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.

MiR-186-5p Downregulates NAMPT and Functions as a Potential Therapeutic Target for Sepsis-Induced Coagulation Disorders

Purpose

Present study is aimed to explore the role of miR-186-5p in sepsis-induced coagulation disorders and molecular mechanisms.

Methods

Thirty-four sepsis patients and 34 respiratory infection/pneumonia patients were selected in the present study. Polymicrobial sepsis model was created by cecal ligation and puncture (CLP). The mRNA expression was detected by qRT-PCR. Western blot was utilized to measure protein expression. Thromborel S Reagent was applied to measure the prothrombin time (PT). Platelet count of blood was measured via LH 780. ELISA kits were utilized to evaluate the fibrinogen and PAI-1 concentration.

Results

MiR-186-5p expression was lower and nicotinamide phosphoribosyltransferase (NAMPT) mRNA expression was higher in sepsis patients in contrast to control group. Coagulation time was markedly prolonged and platelet count was markedly decreased in CLP mice. In addition, fibrinogen concentration was obviously lower and PAI-1 concentration was obviously higher in CLP mice. MiR-186-5p mimic obviously decreased coagulation time and PAI-1 concentration, while raised platelet count and fibrinogen concentration. Targetscan predicted miR-186-5p might directly regulates NAMPT, and luciferase reporter assay verified this prediction. In addition, miR-186-5p mimic obviously inhibited the mRNA expression of NAMPT. Knockdown of NAMPT improved coagulation dysfunction in sepsis. Overexpression of NAMPT reversed the improvement effect of miR-186-5p on coagulation dysfunction. MiR-186-5p mimic markedly inhibited NF-κB pathway.

Conclusion

MiR-186-5p inhibited sepsis-induced coagulation disorders via targeting NAMPT and inactivating NF-κB pathway.

Contribution of MicroRNAs in Chemoresistance to Cisplatin in the Top Five Deadliest Cancer: An Updated Review

Cisplatin (DDP) is a well-known anticancer drug used for the treatment of numerous human cancers in solid organs, including bladder, breast, cervical, head and neck squamous cell, ovarian, among others. Its most important mode of action is the DNA-platinum adducts formation, inducing DNA damage response, silencing or activating several genes to induce apoptosis; these mechanisms result in genetics and epigenetics modifications. The ability of DDP to induce tumor cell death is often challenged by the presence of anti-apoptotic regulators, leading to chemoresistance, wherein many patients who have or will develop DDP-resistance. Cancer cells resist the apoptotic effect of chemotherapy, being a problem that severely restricts the successful results of treatment for many human cancers. In the last 30 years, researchers have discovered there are several types of RNAs, and among the most important are non-coding RNAs (ncRNAs), a class of RNAs that are not involved in protein production, but they are implicated in gene expression regulation, and representing the 98% of the human genome non-translated. Some ncRNAs of great interest are long ncRNAs, circular RNAs, and microRNAs (miRs). Accumulating studies reveal that aberrant miRs expression can affect the development of chemotherapy drug resistance, by modulating the expression of relevant target proteins. Thus, identifying molecular mechanisms underlying chemoresistance development is fundamental for setting strategies to improve the prognosis of patients with different types of cancer. Therefore, this review aimed to identify and summarize miRs that modulate chemoresistance in DDP-resistant in the top five deadliest cancer, both in vitro and in vivo human models.

Using biological information to analyze potential miRNA-mRNA regulatory networks in the plasma of patients with non-small cell lung cancer

Background

Lung cancer is the most common malignant tumor, and it has a high mortality rate. However, the study of miRNA-mRNA regulatory networks in the plasma of patients with non-small cell lung cancer (NSCLC) is insufficient. Therefore, this study explored the differential expression of mRNA and miRNA in the plasma of NSCLC patients.

Methods

The Gene Expression Omnibus (GEO) database was used to download microarray datasets, and the differentially expressed miRNAs (DEMs) were analyzed. We predicted transcription factors and target genes of the DEMs by using FunRich software and the TargetScanHuman database, respectively. The Database for Annotation, Visualization, and Integrated Discovery (DAVID) was used for GO annotation and KEGG enrichment analysis of downstream target genes. We constructed protein-protein interaction (PPI) and DEM-hub gene networks using the STRING database and Cytoscape software. The GSE20189 dataset was used to screen out the key hub gene. Using The Cancer Genome Atlas (TCGA) and UALCAN databases to analyze the expression and prognosis of the key hub gene and DEMs. Then, GSE17681 and GSE137140 datasets were used to validate DEMs expression. Finally, the receiver operating characteristic (ROC) curve was used to verify the ability of the DEMs to distinguish lung cancer patients from healthy patients.

Results

Four upregulated candidate DEMs (hsa-miR199a-5p, hsa-miR-186-5p, hsa-miR-328-3p, and hsa-let-7d-3p) were screened from 3 databases, and 6 upstream transcription factors and 2253 downstream target genes were predicted. These genes were mainly enriched in cancer pathways and PI3k-Akt pathways. Among the top 30 hub genes, the expression of KLHL3 was consistent with the GSE20189 dataset. Except for let-7d-3p, the expression of other DEMs and KLHL3 in tissues were consistent with those in plasma. LUSC patients with high let-7d-3p expression had poor overall survival rates (OS). External validation demonstrated that the expression of hsa-miR-199a-5p and hsa-miR-186-5p in peripheral blood of NSCLC patients was higher than the healthy controls. The ROC curve confirmed that the DEMs could better distinguish lung cancer patients from healthy people.

Conclusion

The results showed that miR-199a-5p and miR-186-5p may be noninvasive diagnostic biomarkers for NSCLC patients. MiR-199a-5p-KLHL3 may be involved in the occurrence and development of NSCLC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09281-1.

Hsa_circ_0017639 regulates cisplatin resistance and tumor growth via acting as a miR-1296-5p molecular sponge and modulating sine oculis homeobox 1 expression in non-small cell lung cancer

Cisplatin (DDP)-induced chemoresistance is an important reason for the failure of non-small cell lung cancer (NSCLC) treatment. Circular RNAs (circRNAs) participate in the chemoresistance of diverse cancers. However, the function of hsa_circ_0017639 (circ_0017639) in the DDP resistance of NSCLC is unclear. Forty-one NSCLC samples (21 DDP-resistant samples and 20 DDP-sensitive samples) were utilized in the research. The relative expression levels of some genes were determined by real-time quantitative polymerase chain reaction (RT-qPCR). 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay for half-maximal inhibitory concentration (IC₅₀) value of DDP and cell viability, colony formation and 5-ethynyl-2’-deoxyuridine (EDU) assays for cell proliferation, flow cytometry assay for cell apoptosis, transwell assay for cell invasion and wound-healing assay for cell migration were performed. The regulation mechanism of circ_0017639 was demonstrated by a dual-luciferase reporter assay. We observed higher levels of circ_0017639 in DDP-resistant NSCLC samples and cells. Functionally, circ_0017639 silencing decreased tumor growth and elevated DDP sensitivity in vivo and induced apoptosis, repressed proliferation, invasion, and migration of DDP-resistant NSCLC cells in vitro. Mechanically, circ_0017639 modulated sine oculis homeobox 1 (SIX1) expression via sponging microRNA (miR)-1296-5p. Also, miR-1296-5p inhibitor restored circ_0017639 knockdown-mediated impacts on cell DDP resistance in DDP-resistant NSCLCs. Furthermore, SIX1 overexpression counteracted the inhibiting impact of miR-1296-5p upregulation on DDP resistance and malignant phenotypes of DDP-resistant NSCLC cells. In conclusion, circ_0017639 conferred DDP resistance and promoted tumor growth via elevating SIX1 expression through sequestering miR-1296-5p in NSCLC, providing a new mechanism for understanding the chemoresistance and progression of NSCLC.

Circular RNA circ-RNF121 contributes to cisplatin (DDP) resistance of non-small-cell lung cancer cells by regulating the miR-646/SOX4 axis

Chemo-resistance is considered a major obstacle in the clinical treatment of non-small-cell lung cancer (NSCLC). Circular RNA (circRNA) circ-RNF121 (hsa_circ_0023404) has been identified to be related to the cisplatin (DDP) resistance. However, the role and mechanism of circ-RNF121 in the DDP resistance in NSCLC are still unknown. Real-time quantitative PCR (RT-qPCR) was applied to detect the levels of circ-RNF121, microRNA-646 (miR-646) and SRY-related HMG box transcription factor 4 (SOX4). Cell viability, proliferation, apoptosis, migration, invasion and cell cycle progression were assessed by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT), colony formation, flow cytometry, wound-healing, transwell and flow cytometry assays, severally. The binding relationship between miR-646 and circ-RNF121 or SOX4 was predicted by the circular RNA interactome or Target Scan Human7.2 and then verified by a dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. SOX4 protein level was measured by western blot assay. The biological role of circ-RNF121 on NSCLC tumor growth and drug resistance was examined by the xenograft tumor model in vivo. Circ-RNF121 and SOX4 were increased, and miR-646 was declined in DDP-resistant NSCLC tissues and cells. Furthermore, the circ-RNF121 deficiency could enhance DDP sensitivity by inhibiting cell proliferation, migration, invasion, cell cycle progression and promoting apoptosis in DDP-resistant NSCLC cells in vitro. Mechanically, circ-RNF121 served as a sponge of miR-646 to increase SOX4 expression. Circ-RNF121 knockdown improved the drug sensitivity of NSCLC in vivo. Circ-RNF121 silencing could reduce the DDP resistance of NSCLC cells by regulating SOX4 expression via miR-646. These findings hinted at a promising therapeutic target for NSCLC treatment.

MiR-186 Suppressed Growth, Migration, and Invasion of Lung Adenocarcinoma Cells via Targeting Dicer1

Objective

Globally, the fatal form of lung cancer is non-small-cell lung cancer (NSCLC), and its most common subtype is lung adenocarcinoma (LUAD). In cancer development and progression, miRNAs play key roles primarily in interacting with cancer-related genes. The main focus of this research was to examine the biological roles of miR-186 in LUAD.

Methods

We examined tissues of LUAD and lung cancer cell lines. The expressions of miR-186, Dicer1, Ki-67, and PCNA were determined by immunohistochemistry (IHC), real-time quantitative PCR (RT-PCR), and western blot assays. The CCK-8 and transwell assays were used to determine cell proliferation, migration, and invasion. To determine the association between miR-186 and Dicer1, a luciferase assay was used.

Results

MiR-186 expression was found to be lower in LUAD tissues, and this was correlated to TNM stage and lymph node metastasis in LUAD patients. miR-186 upregulation significantly reduced the proliferation rate and the level of Ki67 and PCNA of LUAD cell lines HCC827 and A549. Transwell assay exhibited that miR-186 upregulation considerably reduced HCC827 and A549 cells' migration and invasion abilities. Furthermore, we also confirmed that Dicer1 was a direct target of miR-186. Importantly, Dicer1 overexpression abolished the suppression of miR-186 mimics on cell proliferation, migration, and invasion of HCC827 and A549 cells.

Conclusion

These results indicated that the miR-186/Dicer1 pathway is critical for regulating LUAD cell proliferation, migration, and invasion.

Long non-coding RNA (LncRNA) CASC9/microRNA(miR)-590-3p/sine oculis homeobox 1 (SIX1)/NF-κB axis promotes proliferation and migration in breast cancer

Long non-coding RNA (lncRNA)–microRNA–mRNA signaling axes have recently been shown to have a key role in the development of breast cancer (BC). In this study, we investigated how the cancer susceptibility candidate 9 (CASC9) gene affects the cell growth, invasion, migration, and apoptosis of BC cells. The levels of microRNA-590-3p (miR-590-3p), CASC9, and the sine oculis homeobox 1 (SIX1) gene were determined through qRT-PCR. We conducted cell counting kit-8 (CCK-8) assays to assess cell proliferation, transwell assays to detect cell migration/invasion, and flow cytometry to evaluate cell apoptosis. StarBase v2.0 was used to predict interactions between miR-590-3p and SIX1 or CASC9, and dual-luciferase reporter assays were used to verify these predictions. CASC9 protein was overexpressed in BC cells and tissues, while CASC9 knockdown inhibited BC cell growth, invasion, and migration and promoted apoptosis. Additionally, we verified that CASC9 competes for binding with miR-590-3p. Moreover, SIX1 was determined to be a target of miR-590–3p, and SIX1 expression was inhibited by miR-590-3p overexpression. CASC9 enhanced BC development by downregulating miR-590-3p and upregulating SIX1 during the activation of the NF-κB pathway. These data suggest that the CASC9/miR-590-3p/SIX1/NF-κB axis is involved in breast cancer progression, providing insight into the function of CASC9 in breast cancer development.

Knock-down of microRNA miR-556-5p increases cisplatin-sensitivity in non-small cell lung cancer (NSCLC) via activating NLR family pyrin domain containing 3 (NLRP3)-mediated pyroptotic cell death

MicroRNAs (miRNAs) are small non-coding RNAs that are closely associated with cancer progression and drug resistance, however, up until now, the involvement of miR-556-5p in regulating cisplatin-sensitivity in non-small cell lung cancer (NSCLC) has not been studied. In the present study, we found that miR-556-5p was significantly upregulated in the cisplatin-resistant NSCLC (CR-NSCLC) patients’ tissues and cells, instead of the corresponding cisplatin-sensitive NSCLC (CS-NSCLC) tissues and cells. Further experiments validated that knock-down of miR-556-5p suppressed cell viability and tumorigenesis, and induced cell apoptosis in the cisplatin-treated CR-NSCLC cells, and conversely, upregulation of miR-556-5p increased cisplatin-resistance in CS-NSCLC cells. Interestingly, miR-556-5p ablation triggered pyroptotic cell death in cisplatin-treated CR-NSCLC cells via upregulating NLRP3, and the promoting effects of miR-556-5p silence on cisplatin-sensitivity in CR-NSCLC cells were abrogated by both cell pyroptosis inhibitor NSA and NLRP3 downregulation. Taken together, this study firstly evidenced that induction of NLRP3-mediated cell pyroptosis by miR-556-5p downregulation was effective to increase cisplatin-sensitivity in NSCLC, which provided new therapy strategies to overcome chemo-resistance for NSCLC patients in clinic.

circSNX6 (hsa_circ_0031608) enhances drug resistance of non-small cell lung cancer (NSCLC) via miR-137

circRNAs have been suggested to modulate NSCLC tumorigenesis and drug resistance. Whether circSNX6 affects NSCLC remains unclear. In this study, we aim to investigate the role of circSNX6 in drug resistance of NSCLC exposed to cisplatin. RT-qPCR method was used to investigate expression levels of circSNX6, miR-137 and CXCL12. MTT, cell colony formation and TUNEL assays were utilized to assess cell viability, proliferation, apoptosis, respectively. Xenograft assay was conducted to examinein vivotumor growth. circSNX6 overexpression caused enhanced cell viability and proliferation of H1299 and Calu-1, while it inhibited apoptosis under cisplatin treatment. miR-137 inhibitor greatly rescued cell viability, proliferation and apoptosis of circSNX6 knockdown H1299 cells. miR-137 mimic increased ROS generation, as well as reduced GSH and SOD levels, whereas miR-137 inhibitor exerted opposing effect. circSNX6 knockdown also enhanced ROS generation, as well as decreased GSH and SOD levels. CXCL12 partially restored miR-137 mimic-modulated cell viability, proliferation and apoptosis. Herein, our group proposes circSNX6 as key regulator for drug resistance of NSCLC. The findings provide solid groundings for understanding of NSCLC pathogenesis and development of therapeutics.

Circular RNAcirc_0076305 Promotes Cisplatin (DDP) Resistance of Non-Small Cell Lung Cancer Cells by Regulating ABCC1 Through miR-186-5p

Background: Lung cancer is a social problem of increasing concern, and non-small cell lung cancer (NSCLC) accounts for 80%-85% incidence of lung cancer. Cisplatin (DDP) is reported as a first-line chemotherapy drug for NSCLC, but the resistance has became a main obstacle for NSCLC treatment. The high level of circular RNA circ_0076305 was related to the DDP resistance in NSCLC. However, the mechanism of circ_0076305 remains unclear in DDP resistance of NSCLC. Materials and Methods: Exosomes were detected by a transmission electron microscope and nanoparticle tracking analysis. The protein levels of CD63, CD81, P-glycoprotein (P-gp), Lung resistance-related protein, and ATP-binding cassette subfamily C member 1 (ABCC1) were examined by Western blot assay. Circ_0076305, microRNA-186-5p (miR-186-5p), and ABCC1 levels were tested by real-time quantitative polymerase chain reaction. DDP resistance was examined by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide assay. The binding relationship between miR-186-5p and circ_0076305 or ABCC1 was predicted by circRNA interactome or starBase, and then verified by dual-luciferase reporter and RNA immunoprecipitation assays. The effect of circ_0076305 on DDP resistance in NSCLC was examined by xenograft tumor model in vivo. Results: Circ_0076305 was increased in NSCLC cell-derived exosomes, DDP-resistant NSCLC tissues and cells. Circ_0076305 knockdown elevated DDP sensitivity in vitro. Mechanically, circ_0076305 enhanced ABCC1 expression through sponging miR-186-5p, thus regulating DDP resistance of NSCLC. Furthermore, circ_0076305 silencing improved DDP sensitivity of NSCLC in vivo. Conclusion: The results from this study disclosed that circ_0076305 knockdown improved DDP sensitivity by the miR-186-5p/ABCC1 axis in NSCLC, hinting a potential circRNA-targeted therapy for NSCLC.

The Regulatory Network and Potential Role of LINC00973-miRNA-mRNA ceRNA in the Progression of Non-Small-Cell Lung Cancer

Background

The occurrence and development of cancer could be promoted by abnormally competing endogenous RNAs (ceRNA) network. This article aims to determine the prognostic biomarker of ceRNA for non-small-cell lung cancer (NSCLC) prognosis.

Methods

The expression and clinical significance of LINC00973 in NSCLC tissues were analyzed via the The Cancer Genome Atlas (TCGA), Gene Expression Profiling Interactive Analysis (GEPIA), lnCAR, and clinical samples in Taihe Hospital. The biological functions and signaling pathways involved in target genes of ceRNA network were analyzed via Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Survival analysis, univariate and multivariate Cox regression analysis were used for prognostic-related mRNA.

Results

Expression of LINC00973 was increased in NSCLC tissues. High expression of LINC00973 was associated with poor prognosis of NSCLC patients. There were 15 miRNA and 238 differential mRNA in the INC00973-miRNA-mRNA ceRNA network, involving cell migration, endothelial cell proliferation, tumor growth factor (TGF)-β, cellular senescence, phosphatidylinositol 3-hydroxy kinase (PI3K)-Akt, Hippo, Rap1, mitogen-activated protein kinase (MAPK), cell cycle signaling pathway, etc. The expression levels of RTKN2, NFIX, PTX3, BMP2 and LOXL2 were independent risk factors for the poor prognosis of NSCLC patients.

Conclusions

LINC00973-miRNA-mRNA ceRNA network might be the basis for determining pivotal post-translational regulatory mechanisms in the progression of NSCLC. BMP2, LOXL2, NFIX, PTX3 and RTKN2 might be valuable prognostic markers and potential therapeutic targets.

Employing siRNA tool and its delivery platforms in suppressing cisplatin resistance: Approaching to a new era of cancer chemotherapy

Although chemotherapy is a first option in treatment of cancer patients, drug resistance has led to its failure, requiring strategies to overcome it. Cancer cells are capable of switching among molecular pathways to ensure their proliferation and metastasis, leading to their resistance to chemotherapy. The molecular pathways and mechanisms that are responsible for cancer progression and growth, can be negatively affected for providing chemosensitivity. Small interfering RNA (siRNA) is a powerful tool extensively applied in cancer therapy in both pre-clinical (in vitro and in vivo) and clinical studies because of its potential in suppressing tumor-promoting factors. As such oncogene pathways account for cisplatin (CP) resistance, their targeting by siRNA plays an important role in reversing chemoresistance. In the present review, application of siRNA for suppressing CP resistance is discussed. The first priority of using siRNA is sensitizing cancer cells to CP-mediated apoptosis via down-regulating survivin, ATG7, Bcl-2, Bcl-xl, and XIAP. The cancer stem cell properties and related molecular pathways including ID1, Oct-4 and nanog are inhibited by siRNA in CP sensitivity. Cell cycle arrest and enhanced accumulation of CP in cancer cells can be obtained using siRNA. In overcoming siRNA challenges such as off-targeting feature and degradation, carriers including nanoparticles and biological carriers have been applied. These carriers are important in enhancing cellular accumulation of siRNA, elevating gene silencing efficacy and reversing CP resistance.

Silencing SIX1 by miR-7160 inhibits non-small cell lung cancer cell growth

The homeoprotein SIX1 is upregulated in non-small cell lung cancer (NSCLC) and associated with NSCLC tumorigenesis and progression. We identified microRNA-7160 (miR-7160) as a SIX1-targeting miRNA. RNA immunoprecipitation results confirmed a direct binding between miR-7160 and SIX1 mRNA in NSCLC cells. In the primary and established NSCLC cells, forced overexpression of miR-7160 downregulated SIX1 and inhibited cancer cell growth, proliferation, migration and invasion. Furthermore, miR-7160 overexpression induced apoptosis activation in NSCLC cells. Conversely, miR-7160 inhibition elevated SIX1 expression and enhanced NSCLC cell progression in vitro. Restoring SIX1 expression, by an untranslated region-depleted SIX1 expression construct, reversed miR-7160-induced anti-NSCLC cell activity. CRISPR/Cas9-inudced knockout of SIX1 mimicked miR-7160-induced actions and produced anti-NSCLC cell activity. In vivo, intratumoral injection of miR-7160-expressing lentivirus downregulated SIX1 mRNA and inhibited NSCLC xenograft growth in severe combined immunodeficient mice. Significantly, miR-7160 expression is downregulated in human NSCLC tissues and is correlated with SIX1 mRNA upregulation. Collectively, miR-7160 silenced SIX1 and inhibited NSCLC cell growth in vitro and in vivo.

MicroRNA‑186‑5p downregulation inhibits osteoarthritis development by targeting MAPK1

As a chronic degenerative joint disease, the characteristics of osteoarthritis (OA) are degeneration of articular cartilage, subchondral bone sclerosis and bone hyperplasia. It has been reported that microRNA (miR)-186-5p serves a key role in the development of various tumors, such as osteosarcoma, non-small-cell lung cancer cells, glioma and colorectal cancer. The present study aimed to investigate the effect of miR-186-5p in OA. Different concentrations of IL-1β were used to treat the human chondrocyte cell line CHON-001 to simulate inflammation, and CHON-001 cell injury was assessed by detecting cell viability, apoptosis, caspase-3 activity and the levels of TNF-α, IL-8 and IL-6. Subsequently, reverse transcription-quantitative PCR was performed to measure miR-186-5p expression. The results demonstrated that following IL-1β treatment, CHON-001 cell viability was suppressed, apoptosis was promoted, the caspase-3 activity was significantly enhanced and the release of TNF-α, IL-8 and IL-6 was increased. In addition, IL-1β treatment significantly upregulated miR-186-5p expression in CHON-001 cells. It was also identified that MAPK1 was a target gene of miR-186-5p, and was negatively regulated by miR-186-5p. miR-186 inhibitor and MAPK1-small interfering RNA (siRNA) were transfected into CHON-001 cells to investigate the effect of miR-186-5p on CHON-001 cell injury induced by IL-1β. The results demonstrated that miR-186 inhibitor suppressed the effects of IL-1β on CHON-001 cells, and these effects were reversed by MAPK1-siRNA. In conclusion, the present results indicated that miR-186-5p could attenuate IL-1β-induced chondrocyte inflammation damage by increasing MAPK1 expression, suggesting that miR-186-5p may be used as a potential therapeutic target for OA.

LncRNA PART1 promotes lung squamous cell carcinoma progression via miR-185-5p/Six1 axis

Dysregulation of the long non-coding RNA prostate androgen regulated transcript 1 (lncRNA PART1) is involved in the tumorigenesis of various cancers. However, little is known about its function and molecular mechanism in the development of lung squamous cell carcinoma (LSCC). In this study, we examined the expression of PART1 in LSCC clinical tissue samples and cell lines, and gain- and loss-of-function experiments were performed to explore the function of PART1 in LSCC proliferation, invasion and migration. We found that PART1 was overexpressed in both LSCC tissues and cell lines. Functional studies revealed that PART1 knockdown significantly suppressed cell proliferation, invasion and migration but enhanced apoptosis in LSCC cells, whereas overexpression of PART1 showed the opposite results. Mechanistically, we identified that PART1 acted as a sponge of miR-185-5p, and sineoculis homeobox homolog 1 (Six1) was a direct downstream target of miR-185-5p. Moreover, restoration of miR-185-5p or silencing of Six1 partially abolished the oncogenic effect of PART1 in LSCC cells. Clinically, The areas under the receiver operating characteristic (ROC) curve of PART1, miR-185-5p, and Six1 were 0.7857, 0.7332, 0.8112, respectively. Notably, high PART1, low miR-185-5p, and high Six1 expressions were significantly associated with severe clinical parameters and were the independent risk factors for poor prognosis of LSCC patients. Thus, we concluded that the PART1/miR-185-5p/Six1 axis might serve as a novel biomarker for the diagnosis and treatment of LSCC.

The long noncoding RNA FTX promotes a malignant phenotype in bone marrow mesenchymal stem cells via the miR-186/c-Met axis

Gliomas are the most common and aggressive primary tumours of the central nervous system in adults. Bone marrow-derived mesenchymal stem cells (BMSCs) are an important component of the glioma microenvironment. Our previous study indicated that BMSCs in the glioma microenvironment could be induced to malignantly transform by glioma stem cells (GSCs). The malignant transformation of BMSCs is closely related to glioma progression; however, the underlying mechanism of this transformation has not been fully clarified. In this study, we found that compared with the levels in normal BMSCs, the levels of the long noncoding RNA FTX transcript XIST regulator (lncRNA-FTX) were increased in malignantly transformed BMSCs (tBMSCs), which was associated with the proliferation, migration and invasion of tBMSCs. Next, by using a luciferase reporter assay and an RNA pull-down assay, we found that lncRNA-FTX acted as a sponge for miR-186 in tBMSCs. Further research revealed that miR-186 could bind to the 3'-UTR (untranslated region) of c-Met, which acts as an oncogene in gliomas. Through functional assays, we showed that lncRNA-FTX could regulate c-Met expression in tBMSCs in a miR-186-dependent manner. Based on these data, we concluded that lncRNA-FTX plays a key role in the GSC-mediated malignant transformation of BMSCs in the glioma microenvironment, which is of great significance for further understanding the pathogenesis of glioma.

Diagnostic value of miR-186-5p for carotid artery stenosis and its predictive significance for future cerebral ischemic event

BACKGROUND

MicroRNAs (miRNAs) serve as novel promising biomarkers for the diagnosis and prognosis of many human diseases. This study investigated the diagnostic value of miR-186-5p for asymptomatic carotid artery stenosis (CAS), and its predictive value for future cerebral ischemic events (CIEs).

METHODS

Sixty-seven cases with asymptomatic CAS and 60 healthy individuals were recruited. Serum levels of miR-186-5p were tested by using qRT-PCR. Receiving-operator characteristic (ROC) curve was drawn based on sensitivity and specificity analyses. All asymptomatic CAS cases were followed up for 5 years. Kaplan-Meier method was applied for the evaluation of the predictive value of miR-186-5p for the occurrence of CIE.

RESULTS

The serum level of miR-186-5p was increased significantly in asymptomatic CAS patients. MiR-186-5p was the most significant factor associated with the high degree of carotid stenosis in asymptomatic CAS patients. In the ROC curve analysis, the AUC was 0.919, with the sensitivity of 89.6% and specificity of 81.7% at the cutoff value of 1.221. Kaplan-Meier method results revealed that high miR-186-5p level was associated with the occurrence of CIEs. High miR-186-5p level and high degree of carotid stenosis were independent factors for the occurrence of CIEs.

CONCLUSION

MiR-186-5p serves as a potential diagnostic biomarker for patients with asymptomatic CAS, and predicts the occurrence of future CIEs.

MiR-186 represses progression of renal cell cancer by directly targeting CDK6

The function of miR-186 in the progression of renal cell carcinoma (RCC) remains poorly investigated. Our study aims to identify the molecular mechanism underlying miR-186-regulated proliferation, migration and invasion of RCC. Firstly, our data confirmed that miR-186 was significantly reduced and CDK6 was obviously increased in RCC tissues and cells. MiR-186 or CDK6 was associated with advanced TNM stage, lymph node metastasis and poor prognosis. MiR-186 significantly inhibited cell proliferation, migration, invasion and in vivo tumor growth, induced apoptosis, and blocked cell cycle progression in G0/G1 phase. MiR-186 also induced Bax expression and inhibited the expressions of Bcl-2, cyclin D1 and epithelial-mesenchymal transition (EMT)-related genes. Additionally, CDK6 expression was downregulated by miR-186 via binding to its 3'-untranslated region (3'-UTR). Moreover, ectopic expression of CDK6 could partially abrogate the inhibitory effect of miR-186. In conclusion, miR-186 suppresses proliferation, migration and invasion of RCC by inhibiting CDK6 expression.