miRNAs as Biomarkers and Therapeutic Targets in Non-Small Cell Lung Cancer: Current Perspectives

microRNAs, oxidative stress, and genotoxicity as the main inducers in the pathobiology of cancer development

Cancer is one of the most serious leading causes of death in the world. Many eclectic factors are involved in cancer progression including genetic and epigenetic alongside environmental ones. In this account, the performance and fluctuations of microRNAs are significant in cancer diagnosis and treatment, particularly as diagnostic biomarkers in oncology. So, microRNAs manage and control the gene expression after transcription by mRNA degradation, or also they can inhibit their translation. Conspicuously, these molecular structures take part in controlling the cellular, physiological and pathological functions, which many of them can accomplish as tumor inhibitors or oncogenes. Relatively, Oxidative stress is defined as the inequality between the creation of reactive oxygen species (ROS) and the body's ability to detoxify the reactive mediators or repair the resulting injury. ROS and microRNAs have been recognized as main cancer promoters and possible treatment targets. Importantly, genotoxicity has been established as the primary reason for many diseases as well as several malignancies. The procedures have no obvious link with mutagenicity and influence the organization, accuracy of the information, or fragmentation of DNA. Conclusively, mutations in these patterns can lead to carcinogenesis. In this review article, we report the impressive and practical roles of microRNAs, oxidative stress, and genotoxicity in the pathobiology of cancer development in conjunction with their importance as reliable cancer biomarkers and their association with circulating miRNA, exosomes and exosomal miRNAs, RNA remodeling, DNA methylation, and other molecular elements in oncology.

circRNA-CPA4 Regulates Cell Proliferation and Apoptosis of Non-small Cell Lung Cancer via the miR-1183/PDPK1 Axis

Non-small-cell lung cancer (NSCLC) stands as a prevalent subtype of lung cancer, with circular RNAs emerging as key players in cancer development. This study elucidates the role of circRNA-CPA4 in NSCLC. Elevated circRNA-CPA4 expression in NSCLC lines was confirmed through qRT-PCR. Silencing circRNA-CPA4 with shRNA revealed, through CCK-8, colony formation, and flow cytometry assays, a notable constraint on proliferation and promotion of apoptosis in NSCLC cells. Subcellular localization analysis, RNA immunoprecipitation, and expression level assessments were employed to decipher the intricate interplay among miR-1183, circRNA-CPA4, and PDPK1. Results demonstrated heightened circRNA-CPA4 levels in NSCLC, and its knockdown curtailed NSCLC growth in vivo. Acting as a molecular sponge for miR-1183, circRNA-CPA4 regulated PDPK1 expression. Conversely, inhibiting miR-1183 counteracted the impact of circRNA-CPA4 silencing, reinstating NSCLC cell proliferation, and impeding apoptosis. Overall, this study unveils a novel mechanism: circRNA-CPA4 promotes PDPK1 expression by sequestering miR-1183, fostering NSCLC cell proliferation, and hindering apoptosis.

The interaction of mast cells with membranes from lung cancer cells induces the release of extracellular vesicles with a unique miRNA signature

Mast cells (MCs) are immune cells that play roles in both normal and abnormal processes. They have been linked to tumor progression in several types of cancer, including non-small cell lung cancer (NSCLC). However, the exact role of MCs in NSCLC is still unclear. Some studies have shown that the presence of a large number of MCs is associated with poor prognosis, while others have suggested that MCs have protective effects. To better understand the role of MCs in NSCLC, we aimed to identify the initial mechanisms underlying the communication between MCs and lung cancer cells. Here, we recapitulated cell-to-cell contact by exposing MCs to membranes derived from lung cancer cells and confirming their activation, as evidenced by increased phosphorylation of the ERK and AKT kinases. Profiling of the microRNAs that were selectively enriched in the extracellular vesicles (EVs) released by the lung cancer-activated MCs revealed that they contained significantly increased amounts of miR-100-5p and miR-125b, two protumorigenic miRNAs. We explored the pathways regulated by these miRNAs via enrichment analysis using the KEGG database, demonstrating that these two miRNAs regulate p53 signaling, cancer pathways, and pathways associated with apoptosis and the cell cycle.

Recent advances on high-efficiency of microRNAs in different types of lung cancer: a comprehensive review

Carcinoma of the lung is among the most common types of cancer globally. Concerning its histology, it is categorized as a non-small cell carcinoma (NSCLC) and a small cell cancer (SCLC) subtype. MicroRNAs (miRNAs) are a member of non-coding RNA whose nucleotides range from 19 to 25. They are known to be critical regulators of cancer via epigenetic control of oncogenes expression and by regulating tumor suppressor genes. miRNAs have an essential function in a tumorous microenvironment via modulating cancer cell growth, metastasis, angiogenesis, metabolism, and apoptosis. Moreover, a wide range of information produced via several investigations indicates their tumor-suppressing, oncogenic, diagnostic assessment, and predictive marker functions in different types of lung malignancy. miRNA mimics or anti-miRNAs can be transferred into a lung cancer cell, with possible curative implications. As a result, miRNAs hold promise as targets for lung cancer treatment and detection. In this study, we investigate the different functions of various miRNAs in different types of lung malignancy, which have been achieved in recent years that show the lung cancer-associated regulation of miRNAs expression, concerning their function in lung cancer beginning, development, and resistance to chemotherapy, also the probability to utilize miRNAs as predictive biomarkers for therapy reaction.

Prospects of microRNAs as therapeutic biomarkers in non-small cell lung cancer

Lung Cancer, the second most common cancer worldwide, remains the leading cause of cancer-related deaths, contemporarily. More than 85% of identified lung cancer cases are comprised of non-small-cell lung carcinoma (NSCLC). Despite the best advancements in the realm of NSCLC therapy, the five-year survival period of NSCLC patients remains unchanged. Underlying complex molecular heterogeneity, delay in early detection resulting in progression of the disease to its advanced stage and acquired resistance of NSCLC cells during therapy have posed additional challenges for circumventing the discrepancies in treatment strategy. microRNAs (miRNAs) are a class of non-coding RNAs, identified as molecules playing an indispensable role in tumorigenesis & progression and metastasis of several cancers, including NSCLC, either by possessing tumor suppressor or by oncogenic functions. As observed across several studies, miRNA dysregulation has been recognised as a causative mechanism behind NSCLC tumorigenesis. In this review, we discuss the role of miRNAs in NSCLC tumor progression caused by their dysregulation, thereby stating their potential therapeutic application in NSCLC as therapeutic biomarkers. We have also highlighted the recent findings of some of the most widely studied tumor suppressor (miR-486, miR-7 miR-34), and oncogene miRNAs (miR-21, miR-224, miR-135b) that can be further explored for its therapeutic potentialities in the management of NSCLC.

Inhibitory role of bone marrow mesenchymal stem cells-derived exosome in non-small-cell lung cancer: microRNA-30b-5p, EZH2 and PI3K/AKT pathway

Exosomal microRNA (miRNA) exerts potential roles in non-small-cell lung cancer (NSCLC). The current study elucidated the role of miR-30b-5p shuttled by bone marrow mesenchymal stem cells (BMSCs)-derived exosomes in treating NSCLC. Bioinformatics analysis was performed with NSCLC-related miRNA microarray GSE169587 and mRNA data GSE74706 obtained for collection of the differentially expressed miRNAs and mRNAs. The relationship between miR-30b-5p and EZH2 was predicted and confirmed. Exosomes were isolated from BMSCs and identified. BMSCs-derived exosomes overexpressing miR-30b-5p were used to establish subcutaneous tumorigenesis models to study the effects of miR-30b-5p, EZH2 and PI3K/AKT signalling pathway on tumour growth. A total of 86 BMSC-exo-miRNAs were differentially expressed in NSCLC. Bioinfomatics analysis found that BMSC-exo-miR-30b-5p could regulate NSCLC progression by targeting EZH2, which was verified by in vitro cell experiments. Besides, the target genes of miR-30b-5p were enriched in PI3K/AKT signalling pathway. Animal experiments validated that BMSC-exo-miR-30b-5p promoted NSCLC cell apoptosis and prevented tumorigenesis in nude mice via EZH2/PI3K/AKT axis. Collectively, the inhibitory role of BMSC-derived exosomes-loaded miR-30b-5p in NSCLC was achieved through blocking the EZH2/PI3K/AKT axis.

CRISPR-Cas9-mediated gene therapy in lung cancer

As the largest cause of cancer-related deaths worldwide, pulmonary cancer is the most common form of the disease. Several genetic, epigenetic, and environmental factors come into play during the multi-step mechanism of tumorigenesis. The heterogeneity that makes discovering successful therapeutics for pulmonary cancer problematic is significantly influenced by the epigenetic landscape, including DNA methylation, chromatin architecture, histone modifications, and noncoding RNA control. Clinical activity of epigenetic-targeted medicines has been reported in hematological tumors, and these compounds may also have therapeutic effects in solid tumors. Over the course of the past few years, some researchers have successfully modified the expression of genes in cells using the clustered regularly interspaced short palindromic repeats (CRISPR)-Cas (CRISPR-associated proteins) technique. The utilization of this technology allows for the induction of site-specific mutagenesis, epigenetic alterations, and the regulation of gene expression. This study will present an overview of the primary epigenetic alterations seen in pulmonary cancer, as well as a summary of therapeutic implications for targeting epigenetics in the management of pulmonary cancer, with a particular emphasis on the technique known as CRISPR/Cas9.

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

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

LncRNA KCNQ1OT1 enhances the radioresistance of lung squamous cell carcinoma by targeting the miR-491-5p/TPX2-RNF2 axis

BACKGROUND

Lung cancer, especially lung squamous cell carcinoma (LUSC), is one of the most common malignant tumors worldwide. Currently, radiosensitization research is a vital direction for the improvement of LUSC therapy. Long non-coding RNAs (lncRNAs) can be novel biomarkers due to their multiple functions in cancers. However, the function and mechanism of lncRNA KCNQ1OT1 in the radioresistance of LUSC remain to be elucidated.

METHODS

The clonogenic assay was employed to determine the radioresistance of SK-MES-1R and NCI-H226R cells. Real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot were conducted for the detection of gene expression. Cell proliferation was determined by the methyl thiazolyl tetrazolium (MTT) assay, colony formation assay, and 5-ethynyl-2'-deoxyuridine (EdU) staining, and cell apoptosis was assessed by flow cytometry. The relationships between genes were also evaluated by applying the luciferase reporter and radioimmunoprecipitation (RIP) assays.

RESULTS

Radioresistant LUSC cells (SK-MES-1R and NCI-H226R) had strong resistance to X-ray irradiation, and lncRNA KCNQ1OT1 was highly expressed in SK-MES-1R and NCI-H226R cells. Moreover, knockdown of lncRNA KCNQ1OT1 prominently suppressed proliferation, attenuated radioresistance, and accelerated the apoptosis of SK-MES-1R and NCI-H226R cells. More importantly, we verified that miR-491-5p was a regulatory target of lncRNA KCNQ1OT1, and Xenopus kinesin-like protein 2 (TPX2) and RING finger protein 2 (RNF2) were the target genes of miR-491-5p. The rescue experiment results also demonstrated that miR-491-5p was involved in the inhibition of cell proliferation and the downregulation of TPX2 and RNF2 expression mediated by lncRNA KCNQ1OT1 knockdown in SK-MES-1R and NCI-H226R cells.

CONCLUSIONS

LncRNA KCNQ1OT1 was associated with the radioresistance of radioresistant LUSC cells, and the lncRNA KCNQ1OT1/miR-491-5p/TPX2-RNF2 axis might be used as a therapeutic target to enhance the radiosensitivity of radioresistant LUSC cells.

The Transcription Factor Otc4A Stimulates the Proliferation, Invasion, and Stemness of Colorectal Cancer Cells by Inhibiting the Regulation of miR-7-5p on TLR4

Background

To investigate the effects and mechanism of octamer-binding transcription factor 4 (Otc4A) on proliferation, invasion, and stemness of colorectal cancer (CRC) cells.

Methods

Firstly, normal fetal human cells (FHC, colon epithelial cells) and HT29 cells (CRC cells) were cultured. The expression levels of Otc4A, miR-7-5p, and TLR4 in cells were then detected by qRT-PCR. CCK-8 was adopted to measure cell proliferation rate after Otc4A, miR-7-5p, and TLR4, respectively, were either knocked out or overexpressed in HT29 cells. Later, the cell viability was detected by cell cloning assay; cell invasion by transwell; cell sphere-forming ability by sphere-formation assay; protein expression level of Otc4A, p65, p-p65, and TLR4 by western blot; and the targeting relationships between miR-7-5p and Otc4A as well as miR-7-5p and TLR4 by dual-luciferase reporter assay. Finally, chromatin immunoprecipitation was applied to verify the interaction between Otc4A and miR-7-5p.

Results

In HT29 cells, Otc4A expression was significantly increased. Additionally, the knockdown of Otc4A prevented HT29 cells from proliferating, migrating, forming spheres, and activating NF–B signaling. Otc4A could negatively regulate miR-7-5p, and miR-7-5p could target TLR4 expression. Besides, a negative correlation was found between Otc4A and miR-7-5p. Finally, the knockdown of miR-7-5p or overexpression of TLR4 could significantly reverse the effect of the knockdown of Otc4A on HT29 cells.

Conclusion

The transcription factor Otc4A can regulate the level of TLR4 by inhibiting the expression of miR-7-5p and then promote the proliferation and invasion of CRC cell HT29 as well as enhance cell stemness.

Isothermal circular strand displacement-based assay for microRNA detection in liquid biopsy

Extracellular miRNAs are promising targets for developing new assays for the early diagnosis and prognosis of diseases based on liquid biopsy. The detection of miRNAs in liquid biopsies is challenged by their short sequence length, low concentration, and interferences with bodily fluid components. Isothermal circular strand displacement polymerization has emerged as a convenient method for nucleic acid amplification and detection. Herein, we describe an innovative strategy for microRNA detection directly from biological fluids based on hairpin probe–assisted isothermal amplification reaction. We designed and optimized the assay to detect target analytes in 1 µL of the complex media’s biological matrix using a microfluidic device for the straightforward analysis of multiple samples. We validated the assay to detect circulating miR-127-5p in synovial fluid, recently indicated as a predictive biomarker for osteoarthritis disease. The combined use of a mutant polymerase operating with high yield and a primer incorporating locked nucleic acid nucleosides allowed detection of miR-127-5p with 34 fmol L⁻¹ LOD. We quantified circulating miR-127-5p directly in synovial fluid, thus demonstrating that the assay may be employed for the convenient detection of 4.3 ± 0.5 pmol L⁻¹ concentrated miRNAs in liquid biopsy samples.

APE1 controls DICER1 expression in NSCLC through miR-33a and miR-130b

Increasing evidence suggests different, not completely understood roles of microRNA biogenesis in the development and progression of lung cancer. The overexpression of the DNA repair protein apurinic/apyrimidinic endodeoxyribonuclease 1 (APE1) is an important cause of poor chemotherapeutic response in lung cancer and its involvement in onco-miRNAs biogenesis has been recently described. Whether APE1 regulates miRNAs acting as prognostic biomarkers of lung cancer has not been investigated, yet. In this study, we analyzed miRNAs differential expression upon APE1 depletion in the A549 lung cancer cell line using high-throughput methods. We defined a signature of 13 miRNAs that strongly correlate with APE1 expression in human lung cancer: miR-1246, miR-4488, miR-24, miR-183, miR-660, miR-130b, miR-543, miR-200c, miR-376c, miR-218, miR-146a, miR-92b and miR-33a. Functional enrichment analysis of this signature revealed its biological relevance in cancer cell proliferation and survival. We validated DICER1 as a direct functional target of the APE1-regulated miRNA-33a-5p and miR-130b-3p. Importantly, IHC analyses of different human tumors confirmed a negative correlation existing between APE1 and Dicer1 protein levels. DICER1 downregulation represents a prognostic marker of cancer development but the mechanisms at the basis of this phenomenon are still completely unknown. Our findings, suggesting that APE1 modulates DICER1 expression via miR-33a and miR-130b, reveal new mechanistic insights on DICER1 regulation, which are of relevance in lung cancer chemoresistance and cancer invasiveness.

Long non‑coding RNA LINC01748 exerts carcinogenic effects in non‑small cell lung cancer cell lines by regulating the microRNA‑520a‑5p/HMGA1 axis

The important functions of long non‑coding RNAs in the malignancy of non‑small cell lung cancer (NSCLC) has been increasingly highlighted. However, whether LINC01748 functions in a crucial regulatory role still requires further research. The aim of the present study was to investigate the biological roles of LINC01748 in NSCLC. Furthermore, different experiments were utilized to investigate the mechanism of action of LINC01748 in 2 NSCLC cell lines. Reverse transcription‑quantitative PCR was used to measure mRNA expression levels. Cell Counting Kit‑8 assay, flow cytometry analysis and Transwell and Matrigel assays were also used to analyze, cell viability, apoptosis, and migration and invasion, respectively. A tumor xenograft model was used for in vivo experiments. RNA immunoprecipitation experiments, luciferase reporter assays and rescue experiments were used to investigate the mechanisms involved. Data from The Cancer Genome Atlas dataset and patients recruited into the present study showed that LINC01748 was overexpressed in NSCLC. Patients with high LINC01748 mRNA expression level had shorter overall survival rate compared with that in patients with low LINC01748 mRNA expression level. Then, knockdown of LINC01748 mRNA expression level reduced cell proliferation, migration and invasion, but increased cell apoptosis in vitro. Knockdown of LINC01748 also reduced tumor growth in vivo. Mechanistically, LINC01748 could act as a competing endogenous (ce)RNA to sponge microRNA(miR)‑520a‑5p, to increase the expression level of the target gene, high mobility group AT‑hook 1 (HMGA1) in the NSCLC cell lines. Furthermore, rescue experiments illustrated that the functions exerted by LINC01748 knockdown were negated by miR‑520a‑5p inhibition or HMGA1 overexpression. In summary, LINC01748 acted as a ceRNA by sponging miR‑520a‑5p, leading to HMGA1 overexpression, thus increasing the aggressiveness of the NSCLC cells. Accordingly, targeting the LINC01748/miR‑520a‑5p/HMGA1 pathway may benefit NSCLC therapy.

MiroRNA-31-3p Promotes the Invasion and Metastasis of Non-Small-Cell Lung Cancer Cells by Targeting Forkhead Box 1 (FOXO1)

OBJECTIVE

To explore the possibility of microRNA miR-31-3p as a biomarker for bone metastasis of non-small-cell lung cancer (NSCLC) and its molecular mechanism to the invasion and metastasis of NSCLC cells.

METHODS

Real-time quantitative PCR (RT-qPCR) was used to detect the expression levels of miR-31-3p and forkhead box 1 (FOXO1) in NSCLC tissues, serum, and cells to analyze the correlation between the expression levels of miR-31-3p and the clinicopathology of NSCLC. After interference with or overexpressing miR-31-3p, NSCLC cell proliferation, apoptosis, invasion ability, and migration ability were detected by MTT, flow cytometry, Transwell, and scratch experiment, respectively. The interaction between miR-31-3p and FOXO1 was further verified by the dual-luciferase reporter experiment. Western blot was performed to detect the protein expression of FOXO1 in tissues and FOXO1, RhoA, p-RhoA, ROCK-2, and p-ROCK-2 in cells.

RESULTS

In tissues, serum, and NSCLC cell line A549 of the NSCLC patients, the expression of FOXO1 was notably lower, and the miR-31-3p expression was significantly higher. Overexpression of miR-31-3p could distinctly improve the proliferation, invasion, and migration of A549 cells, meanwhile inhibit cell apoptosis, and activate the RhoA/ROCK-2 signaling pathway, while interfering with the expression of miR-31-3p has the opposite function. Besides, bioinformatics analysis and luciferase reporter assay confirmed that FOXO1 was a target gene of miR-31-3p. Overexpressing FOXO1 could inhibit the proliferation and metastasis of A549 cells, but overexpressing miR-31-3p reverses the results.

CONCLUSION

This study confirmed that miR-31-3p promotes the proliferation, invasion, and migration of NSCLC cells and inhibits apoptosis through targeted regulating FOXO1 and be a potential therapeutic targets for the treatment of NSCLC.

JMJD2C-mediated long non-coding RNA MALAT1/microRNA-503-5p/SEPT2 axis worsens non-small cell lung cancer

Jumonji domain containing protein 2C (JMJD2C) could epigenetically regulate cancer cells. We specifically explored the downstream mechanism of JMJD2C in non-small cell lung cancer (NSCLC) from the long non-coding RNA metastasis associated with lung adenocarcinoma transcript 1/microRNA-503-5p/septin 2 (MALAT1/miR-503-5p/SEPT2) axis. NSCLC clinical tissues were utilized to assess JMJD2C, MALAT1, miR-503-5p and SEPT2 levels. NSCLC cell lines (A549 and H1299) were applied for loss-of-function and gain-of-function tests to identify the functional roles of JMJD2C, MALAT1, miR-503-5p, and SEPT2. The interactions among JMJD2C, MALAT1, miR-503-5p, and SEPT2 were assessed. Augmented JMJD2C, MALAT1, and SEPT2 and reduced miR-503-5p levels were found in NSCLC. Depleting JMJD2C or MALAT1, or restoring miR-503-5p exerted anti-tumor effects on NSCLC cells in vitro and in vivo. JMJD2C is bound to the promoter of MALAT1. MALAT1 bound to miR-503-5p and miR-503-5p targeted SEPT2. Knocking down MALAT1 or SEPT2, or elevating miR-503-5p mitigated the pro-tumor effects of upregulated JMJD2C on NSCLC. It is evident that the JMJD2C-mediated MALAT1/miR-503-5p/SEPT2 axis takes part in the process of NSCLC and even worsens NSCLC.

Circ_0026134 promotes NSCLC progression by the miR-3619-5p/CHAF1B axis

BACKGROUND

Non-small cell lung cancer (NSCLC) is the leading cause of cancer death worldwide. Circular RNAs (circRNAs) have been implicated in the pathogenesis of NSCLC. In this study, we explored the molecular determinants underlying the oncogenic property of circ_0026134 in NSCLC.

METHODS

The levels of circ_0026134, miR-3619-5p and chromatin assembly factor 1 subunit B axis (CHAF1B) were assessed by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Cell colony formation, migration, invasion and apoptosis were detected by colony formation, Transwell, and flow cytometry assays, respectively. Direct relationships among circ_0026134, miR-3619-5p and CHAF1B were verified by dual-luciferase reporter assays.

RESULTS

Our results showed that circ_0026134 was highly expressed in NSCLC tissues and cells. Reduced circ_0026134 expression or miR-3619-5p overexpression inhibited NSCLC cell colony formation, migration, invasion, glycolysis and promoted cell apoptosis in vitro. Moreover, circ_0026134 directly targeted miR-3619-5p, and circ_0026134 regulated CHAF1B expression through miR-3619-5p. CHAF1B was a downstream effector of circ_0026134 in affecting NSCLC cell functional behaviors in vitro. Additionally, circ_0026134 silencing weakened tumor growth in vivo.

CONCLUSIONS

Our study identified a novel regulatory mechanism, the circ_0026134/miR-3619-5p/CHAF1B axis, for the oncogenic role of circ_0026134 in NSCLC, highlighting circ_00261345 inhibition as a potential therapeutic method against NSCLC.

Computational and Bioinformatics Methods for MicroRNA Gene Prediction

MicroRNAs (miRNAs) are 20-24-nucleotide-long noncoding RNAs that bind to the untranslated region (3' UTR) of their target mRNAs. The importance of miRNAs in medicine has grown rapidly in the 20 years since the discovery of them. As the regulatory function of miRNAs on biological processes was discovered, they were advocated to play a role in the underlying mechanisms of human pathogenesis. Functional studies have confirmed that miRNAs are promising in preclinical development through deregulation of genes targeted by miRNAs in many cancer cases. In this chapter, we summarize the miRNAs identified for some specific types of cancer and their functions. Besides, miRNAs function as cancer biomarker and their benefits to diagnosis and treatment of cancer are also discussed.

MicroRNA-506 has a suppressive effect on the tumorigenesis of nonsmall-cell lung cancer by regulating tubby-like protein 3

MicroRNA-506 (miR-506), a miRNA, has been proven to act as a tumor suppressor gene in nonsmall-cell lung cancer (NSCLC); Tubby-like protein 3 (TULP3) is a potential target gene of miR-506. This study investigates whether miR-506 can prevent NSCLC progression by mediating TULP3. In vivo and in vitro experiments were performed to explore the function and potential regulatory relationship of miR-506 and TULP3 in NSCLC. Our results revealed that miR-506 is high expression in NSCLC cell lines, and the overexpression of miR-506 could inhibit cell viability and enhance cell apoptosis in H1299 and A549 cells. Pro-apoptotic related protein (cytochrome C, Bax, and cleaved caspase-9) expression increased while anti-apoptotic related protein (BCL-2 and BCL-XL) expression decreased after miR-506 was overexpression. Meanwhile, the overexpression of miR-506 could notably downregulate TULP3. Additionally, silence of TULP3 inhibited cell viability and promoted cell apoptosis. At the same time, pro-apoptotic related protein expression was promoted while anti-apoptotic related protein expression was inhibited. Furthermore, TULP3 overexpression could markedly reverse the inhibitory effect of miR-506 on the proliferation and induction of mitochondrial apoptosis in H1299 and A549 cells. In vivo tumor formation experiments also exhibited consistent results indicating that the functions of TULP3 might be correlated with the promotion of tumorigenesis. In conclusion, we firstly found that miR-506 can be involved in the processes of NSCLC and exert a suppressive effect on tumorigenesis by regulating TULP3 expression.

Non-coding RNAs and their bioengineering applications for neurological diseases

Engineering of cellular biomolecules is an emerging landscape presenting creative therapeutic opportunities. Recently, several strategies such as biomimetic materials, drug-releasing scaffolds, stem cells, and dynamic culture systems have been developed to improve specific biological functions, however, have been confounded with fundamental and technical roadblocks. Rapidly emerging investigations on the bioengineering prospects of mammalian ribonucleic acid (RNA) is expected to result in significant biomedical advances. More specifically, the current trend focuses on devising non-coding (nc) RNAs as therapeutic candidates for complex neurological diseases. Given the pleiotropic and regulatory role, ncRNAs such as microRNAs and long non-coding RNAs are deemed as attractive therapeutic candidates. Currently, the list of non-coding RNAs in mammals is evolving, which presents the plethora of hidden possibilities including their scope in biomedicine. Herein, we critically review on the emerging repertoire of ncRNAs in neurological diseases such as Alzheimer’s disease, Parkinson’s disease, neuroinflammation and drug abuse disorders. Importantly, we present the advances in engineering of ncRNAs to improve their biocompatibility and therapeutic feasibility as well as provide key insights into the applications of bioengineered non-coding RNAs that are investigated for neurological diseases.

Long non-coding RNA DLX6-AS1 knockdown suppresses the tumorigenesis and progression of non-small cell lung cancer through microRNA-16-5p/BMI1 axis

BACKGROUND

Non-small cell lung cancer (NSCLC) is a huge threat to sufferers' life and overall health. Long non-coding RNA (lncRNA) distal-less homeobox 6 antisense RNA 1 (DLX6-AS1) has been revealed to function as a carcinogenesis factor in some cancers. This research aimed to scrutinize the role and mechanism underlying DLX6-AS1 in NSCLC tumorigenesis and progression.

METHODS

The levels of DLX6-AS1, microRNA-16-5p (miR-16-5p), and BMI1 mRNA were estimated via reverse transcription-quantitative PCR (RT-qPCR) assay. The protein levels were disclosed by western blot assay. Cell proliferative potential was estimated by colony formation and Cell Counting Kit-8 (CCK-8) assays. Cell migration was estimated by Transwell and wound healing assay. A Transwell assay was executed to estimate cell invasion. The relationships of DLX6-AS1, miR-16-5p, and BMI1 were forecasted by bioinformatics analysis, and confirmed by luciferase reporter assay and RNA immunoprecipitation (RIP) assay. A xenograft mice model was employed to to inspect the function of DLX6-AS1 knockdown on NSCLC tumorigenesis in vivo.

RESULTS

DLX6-AS1 was overexpressed in NSCLC tissues and cells, and was inextricably linked with the poor prognosis of NSCLC patients. Depletion of DLX6-AS1 oppressed cell proliferation, migration, invasion, epithelial-mesenchymal transition (EMT) but promoted apoptosis in NSCLC. MiR-16-5p is a target of DLX6-AS1 and directly targets BMI1. Moreover, the anti-tumor impacts of miR-16-5p were overturned by overexpression of DLX6-AS1 or BMI1 in NSCLC cells. Additionally, DLX6-AS1 silencing inhibited tumor growth of NSCLC in vivo.

CONCLUSIONS

In conclusion, lncRNA DLX6-AS1 downregulation suppressed the tumorigenesis and progression of NSCLC via miR-16-5p/BMI1 axis in vitro and in vivo, elucidating the vital roles and downstream targets of DLX6-AS1 in NSCLC.

Circular RNA circLDB2 functions as a competing endogenous RNA to suppress development and promote cisplatin sensitivity in non-squamous non-small cell lung cancer

Background

Circular RNAs (circRNAs) are covalently closed RNAs and are implicated in the development of non‐small cell lung cancer (NSCLC). Here, we identified the precise actions of circRNA LIM domain binding 2 (circLDB2, hsa_circ_0069244) in non‐squamous NSCLC development and drug sensitivity.

Methods

CircLDB2, microRNA (miR)‐346, and LIM and calponin‐homology domains 1 (LIMCH1) were quantified by quantitative real‐time polymerase chain reaction (qRT‐PCR) or western blot. Ribonuclease R (RNase R), actinomycin D, and subcellular localization assays were used to characterize circLDB2. Cell proliferation and viability, colony formation, apoptosis, migration, and invasion were gauged by Cell Counting Kit‐8 (CCK‐8), colony formation, flow cytometry, wound‐healing, and transwell assays, respectively. RNA immunoprecipitation (RIP), RNA pull‐down, and dual‐luciferase reporter assays were used to verify the direct relationship between miR‐346 and circLDB2 or LIMCH1. Animal studies were performed to evaluate the impact of circLDB2 in vivo.

Results

CircLDB2 was underexpressed in non‐squamous NSCLC and was identified as a bona fide circular transcript. Overexpression of circLDB2 impeded cell proliferation, migration, invasion, and enhanced apoptosis and cisplatin sensitivity in vitro, as well as promoted the antitumor effect of cisplatin in vivo. CircLDB2 regulated cell functional behaviors and cisplatin sensitivity by sponging miR‐346. LIMCH1 was a direct and functional target of miR‐346. Furthermore, circLDB2 acted as a competing endogenous RNA (ceRNA) for miR‐346 to induce LIMCH1 expression.

Conclusion

Our findings demonstrated that circLDB2 impeded non‐squamous NSCLC development and enhanced cisplatin sensitivity partially by acting as a ceRNA, highlighting circLDB2 as a promising candidate for the development of novel antitumor therapies.

Comparison of oncolytic virotherapy and nanotherapy as two new miRNA delivery approaches in lung cancer

Lung cancer is known as the second leading cause of cancer death. Finding ways to detect early-stage lung cancer can remarkably increase the survival rate. Biomarkers such as microRNAs can be helpful in cancer diagnosis, predicting its prognosis, and patients' chances of survival. Numerous studies have confirmed the correlation between microRNA expression and the likelihood of patients surviving after treatment. Consequently, it is necessary to study the expression profile of microRNAs during and after treatment. Oncolytic virotherapy and nanotherapy are two neoteric methods that use various vectors to deliver microRNAs into cancer cells. Although these treatments have not yet entered into the clinical trials, much progress has been made in this area. Analyzing the expression profile of microRNAs after applying nanotherapy and oncolytic virotherapy can evaluate the effectiveness of these methods. This review refers to the studies conducted about these two approaches. The advantages and disadvantages of these methods in delivery and affecting microRNA expression patterns are discussed below.

miR-371b-5p promotes cell proliferation, migration and invasion in non-small cell lung cancer via SCAI

Objective: Multiple gene targets have been reported for treatment of non-small cell lung cancer (NSCLC), however, the accompanying genetic tolerance was reported increasingly. Therefore, it is important to find new biomarkers or therapeutic targets in treatment of NSCLC.

Methods: The expression levels of miR-371b-5p were detected by qRT-PCR in NSCLC tissues and cell lines. To evaluate the effect of miR-371b-5p on NSCLC progression, we first transfected the miR-371b-5p inhibitor for construction of the miR-371b-5p down-regulated cell model. Then the cell proliferation, migration, invasion and cell apoptosis were detected. In addition, the expression levels of adhesion factors were detected. The target gene of miR-371b-5p was identified by bioinformatics analysis, and rescue experiment was conducted to validate the effect of miR-371b-5p on proliferation, migration and invasion of NSCLC.

Results: Our findings revealed that the miR-371b-5p was overexpressed in NSCLC and could markedly promote the cell proliferation, migration and invasion. Expression levels of both intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were significantly down-regulated when treated by miR-371b-5p inhibitor. Moreover, dual-luciferase reporter assay showed that the miR-371b-5p targeted SCAI in regulation of cell proliferation, migration and invasion, and the expression of miR-371b-5p was negatively associated with SCAI in NSCLC tissues and cell lines. Rescue experiment revealed that the miR-371b-5p could rescue the effect of SCAI on cell proliferation, migration and invasion.

Conclusion: Our results suggest that the miR-371b-5p and SCAI may serve as novel prognostic biomarkers and therapeutic targets for NSCLC.

Strategic targeting of non-small-cell lung cancer utilizing genetic material-based delivery platforms of nanotechnology

Several limitations of conventional cancer treatment such as non-specific targeting, solubility problems, and ineffective entry of chemotherapeutics into cancer cells can be overcome by using nanotechnology targeted drug delivery systems. Some combinations of biomolecules and nanoparticles have proven to be excellent therapeutics for Non-small cell lung cancer (NSCLC) in the last decades. Targeted gene delivery has shown in vivo as well as in vitro promising results with therapeutic efficacy. Gene therapy has shown enhanced transfection efficiency and better targeting potential on several NSCLC cell lines. Still, there are several challenges in nanoparticle-mediated gene therapy, which include stability of biomolecules and nanoparticles during delivery, managing their biodistribution, and reducing the possible cytotoxic effects of the nanoparticles, which need to be solved before clinical trials. Evaluation of therapeutic efficacy of biomolecules and nanoparticle combination in gene therapy must be established to expand the application of nano-gene therapy in cancer treatment.

Exosomal miR-4443 promotes cisplatin resistance in non-small cell lung carcinoma by regulating FSP1 m6A modification-mediated ferroptosis

AIMS

Exosomal transfer of miRNAs affects recipient cell proliferation and chemoresistance. Here, we aimed to investigate the role of exosomal miRNAs in controlling cisplatin resistance in non-small cell lung carcinoma (NSCLC).

MAIN METHODS

Paired tumor and normal tissue-derived exosomes were collected from NSCLC patients with low or high responsiveness to cisplatin treatment. The results showed that the microRNA-4443 (miR-4443) level was upregulated in cisplatin-resistant NSCLC tumor tissue-derived exosomes compared with cisplatin-sensitive tissue-derived exosomes. Cisplatin-resistant cells (A549-R) were generated from the parental cells (A549-S). Resistant exosomes conferred cisplatin resistance by transferring miR-4443 to sensitive cells. Moreover, overexpression of miR-4443 inhibited FSP1-mediated ferroptosis induced by cisplatin treatment in vitro and enhanced tumor growth in vivo.

KEY FINDINGS

Through bioinformatics analysis and luciferase assays, METTL3 was confirmed as a direct target gene of miR-4443. Further mechanistic analysis showed that miR-4443 regulated the expression of FSP1 in an m6A manner via METLL3.

SIGNIFICANCE

Our findings provide more in-depth insight into the chemoresistance of NSCLC and support the therapeutic potential of targeting ferroptosis.

miR-135a inhibits malignant proliferation and diffusion of non-small cell lung cancer cells by down-regulating ROCK1 protein

Objective: To seek the clinical significance and regulatory mechanism of miR-135a and Rho-associated protein kinase 1 (ROCK1) in non-small cell lung cancer (NSCLC).

Methods: NSCLC cells were purchased, and miR-135a-mimics, miR-135a-inhibitor, miR-NC, si-ROCK1 and Sh-ROCK1 were transfected into NSCLC cells HCC827 and NCI-H524. qRT-PCR and Western blot were used to detect the expression of miR-135a, ROCK1, Bax, Caspase3, Bcl-2, N-cadherin, vimentin and E-cadherin. MTT, scratch test, Transwell and flow cytometry were used to analyze the cell proliferation, migration, invasion and apoptosis.

Results: miR-135a was low expressed in serum of NSCLC group, while ROCK1 was opposite. miR-135a low level or ROCK1 high level was associated with poor prognosis of NSCLC and lower 3-year OS. Over-expression of miR-135a and inhibition of ROCK1 expression could control malignant growth and diffusion of cells and expression of Bcl-2, N-cadherin and vimentin proteins, and promote apoptosis and expression of Bax, Caspase3 and E-cadherin proteins. After transfection of miR-135a-mimics+sh-ROCK1 to HCC827 and NCI-H524, the malignant proliferation and diffusion behavior of the cells were not different from those of the miR-NC group with no transfection sequence. The double luciferase report revealed that miR-135a has a targeting relationship with ROCK1.

Conclusion: miR-135a is abnormally down-regulated in NSCLC. As a serum indicator, miR-135a has the potential to diagnose NSCLC and predict prognosis. The up-regulated expression of miR-135a protein can down-regulate the ROCK1 protein, inhibit the malignant proliferation, migration, invasion, EMT and other diffusion behaviors of NSCLC cells, and increase the apoptosis ability of cells.

Attenuating role of withaferin A in the proliferation and migration of lung cancer cells via a p53-miR-27a/miR-10b pathway

MicroRNAs (miRNAs/miRs) are known to play a key role in tumorigenesis and usually serve as therapeutic targets in cancer treatment. In the present study, the inhibitory effects and the targeting miRNAs of withaferin A (WA) were investigated in human lung cancer cells. Different lung cancer cell lines were administrated with different concentrations of WA for different time interval followed by western blot or reverse transcription-quantitative PCR analyses to determine the underlying signaling pathway. The results demonstrated that WA decreased the viability of lung cancer cells in a caspase-dependent manner. Further investigations indicated that treatment with WA induced the expression of proapoptotic molecules, p53 and Bax, and decreased Bcl-2 expression in A549 cells. Notably, the results demonstrated that WA also decreased the motility of lung cancer cells in a dose-dependent manner, at a relatively lower concentration. Western blot analysis revealed increased E-cadherin and decreased vimentin expression levels in lung cancer cells treated with WA. In addition, two oncomiRs, including miR-10b and miR-27a, which regulate the expression of E-cadherin and Bax, respectively, were downregulated in the presence of WA. The ectopic expression of miR-10b mimics was able to recover the WA-decreased motility of lung cancer cells, which was accompanied by a reduction in E-cadherin expression. Conversely, the ectopic expression of miR-27a mimics decreased the expression of Bax and recovered the viability of lung cancer cells attenuated by WA. In addition, the ectopic expression of p53-wild type decreased the expression levels of both miR-10b and miR-27a, whereas p53 knockdown induced their expression. Transient knockdown of p53 decreased the inhibitory effects of WA in the motility and viability of lung cancer cells, suggesting an association between WA-p53-miR-10b/27a and motility/viability. Further investigations demonstrated that p53 knockdown in lung cancer stable cell lines exhibited higher levels of both miR-10b and miR-27a, and higher motility and viability following treatment with WA. However, suppression of miR-10b and miR-27a effectively decreased motility and viability, respectively, following treatment with WA. Taken together, the results of the present study suggest that WA inhibits the functionality of lung cancer cells by decreasing the expression levels of both miR-10b and miR-27a in a p53-dependent manner.

Hsa_circ_0006571 promotes spinal metastasis through sponging microRNA-138 to regulate sirtuin 1 expression in lung adenocarcinoma

Background

Circular RNAs (circRNAs) are known to participate in lung cancer. However, their role in spinal metastasis (SM) of lung adenocarcinoma remains elusive. In this study, we determined that hsa_circ_0006571 serves as a sponge for miR-138, which targets sirtuin 1 (Sirt1) in the development of SM.

Methods

A human circRNA microarray was performed to compare SM and lung adenocarcinoma samples. The expression of hsa_circ_0006571 and miR-138 was determined using quantitative polymerase chain reaction (qPCR) in vitro and in vivo. Cell proliferation was performed by Cell Counting Kit-8 (CCK-8) and apoptosis was analyzed by Annexin V/PI staining. RNA-pulldown and RNA immunoprecipitation (RIP) were used to analyze the interaction between hsa_circ_0006571. Tumor metastasis was determined through a xenograft experiment in vivo.

Results

Hsa_circ_0006571 was observed to be significantly upregulated in SM tissues through circRNA microarray and qPCR. We detected a lower expression of miR-138 in SM tissues compared with lung adenocarcinoma. Hsa_circ_0006571 silencing suppressed lung cancer cell proliferation and migration while promoting apoptosis. Hsa_circ_0006571 interacted with miR-138 to promote expression of Sirt1, leading to activation of epithelial-mesenchymal transition (EMT). Xenograft experiments showed that downregulation of hsa_circ_0006571 delayed the SM of lung adenocarcinoma cells via the miR-138-Sirt1 axis.

Conclusions

Hsa_circ_0006571 promoted tumor cell migration and invasion via the miR-138/Sirt1 pathway. Our observations indicate that circRNAs are possible novel therapeutic targets for SM of lung adenocarcinoma.

Pan-cancer analysis of somatic mutations in miRNA genes

Background

miRNAs are considered important players in oncogenesis, serving either as oncomiRs or suppressormiRs. Although the accumulation of somatic alterations is an intrinsic aspect of cancer development and many important cancer-driving mutations have been identified in protein-coding genes, the area of functional somatic mutations in miRNA genes is heavily understudied.

Methods

Here, based on the analysis of large genomic datasets, mostly the whole-exome sequencing of over 10,000 cancer/normal sample pairs deposited within the TCGA repository, we undertook an analysis of somatic mutations in miRNA genes.

Findings

We identified and characterized over 10,000 somatic mutations and showed that some of the miRNA genes are overmutated in Pan-Cancer and/or specific cancers. Nonrandom occurrence of the identified mutations was confirmed by a strong association of overmutated miRNA genes with KEGG pathways, most of which were related to specific cancer types or cancer-related processes. Additionally, we showed that mutations in some of the overmutated genes correlate with miRNA expression, cancer staging, and patient survival.

Interpretation

Our study is the first comprehensive Pan-Cancer study of cancer somatic mutations in miRNA genes. It may help to understand the consequences of mutations in miRNA genes and the identification of miRNA functional mutations. The results may also be the first step (form the basis and provide the resources) in the development of computational and/or statistical approaches/tools dedicated to the identification of cancer-driver miRNA genes.

Funding

This work was supported by research grants from the Polish National Science Centre 2016/22/A/NZ2/00184 and 2015/17/N/NZ3/03629.

PAQR3 Inhibits Non-small Cell Lung Cancer Growth by Regulating the NF-κB/p53/Bax Axis

Background

The expression of progestin and adipoQ receptor 3 (PAQR3) is generally downregulated in multiple tumors, which is associated with tumor progression and poor prognosis.

Methods

The clinical value of PAQR3 was analyzed using various databases and in 60 patients with non-small cell lung cancer (NSCLC). In addition, cell counting kit-8 (CCK-8), colony formation, and flow cytometry assays were used to evaluate the effect of PAQR3 on the growth of NSCLC cells in vitro. Gene set enrichment analysis (GSEA) was performed to investigate the possible mechanism through which PAQR3 is involved in the progression of lung cancer. Furthermore, western blotting was employed to verify the relevant mechanism.

Results

The expression of PAQR3 was decreased in 60 NSCLC patients and was related to the histological subtype, lymph node metastasis, tumor size, and diagnosis of NSCLC. Patients with lung adenocarcinoma with increased PAQR3 expression tended to have a better prognosis. Besides, PAQR3 inhibited proliferation, clone formation, and cycle transition in NSCLC cells, but induced apoptosis. The results of GSEA showed that PAQR3 regulated the progression of lung cancer by affecting cell cycle, DNA replication, and the p53 signaling pathway. We confirmed that PAQR3 overexpression inhibited the expression of NF-κB, while it increased the expression of p53, phospho-p53, and Bax. On the contrary, PAQR3 inhibition played an opposite role in these proteins.

Conclusion

PAQR3 inhibited the growth of NSCLC cells through the NF-κB/P53/Bax signaling pathway and might be a new target for diagnosis and treatment.

Targeting respiratory diseases using miRNA inhibitor based nanotherapeutics: Current status and future perspectives

MicroRNAs (miRNAs) play a fundamental role in the developmental and physiological processes that occur in both animals and plants. AntagomiRs are synthetic antagonists of miRNA, which prevent the target mRNA from suppression. Therapeutic approaches that modulate miRNAs have immense potential in the treatment of chronic respiratory disorders. However, the successful delivery of miRNAs/antagomiRs to the lungs remains a major challenge in clinical applications. A range of materials, namely, polymer nanoparticles, lipid nanocapsules and inorganic nanoparticles, has shown promising results for intracellular delivery of miRNA in chronic respiratory disorders. This review discusses the current understanding of miRNA biology, the biological roles of antagomiRs in chronic respiratory disease and the recent advances in the therapeutic utilization of antagomiRs as disease biomarkers. Furthermore our review provides a common platform to debate on the nature of antagomiRs and also addresses the viewpoint on the new generation of delivery systems that target antagomiRs in respiratory diseases.

MiR-654-3p Suppresses Non-Small Cell Lung Cancer Tumourigenesis by Inhibiting PLK4

Purpose

MiR-654-3p plays important roles in many types of malignant tumours. However, the biological function of miR-654-3p in non-small cell lung cancer (NSCLC) remains unknown. In this study, the role of miR-654-3p in NSCLC was investigated.

Methods

qRT-PCR was used to evaluate the level of miR-654-3p in NSCLC tissues and cell lines, while Cell Counting Kit-8, Annexin V/propidium iodide dual staining or TUNEL staining were used to investigate proliferation and apoptosis of NSCLC cells. Luciferase assays and Western blotting were performed to validate potential targets of miR-654-3p.

Results

MiR-654-3p levels were significantly decreased in NSCLC patients and cell lines and were significantly correlated with the tumour size and tumour node metastasis stage of NSCLC patients. In A549 cells, miR-654-3p overexpression significantly increased apoptosis and inhibited growth both in vivo and in vitro, while downregulation of miR-654-3p had the opposite effects. In addition, polo-like kinase 4 (PLK4) was shown to be a target gene of miR-654-3p that is negatively regulated by miR-654-3p in A549 cells. Furthermore, PLK4 was observed to be highly expressed in NSCLC tissues and cells, and PLK4 overexpression abolished the inhibitory effects of miR-654-3p overexpression on NSCLC cell proliferation. Finally, the animal experiment results further demonstrated that miR-654-3p inhibits tumour growth and regulates PLK4 expression.

Conclusion

Our results demonstrate that miR-654-3p functions as a growth-suppressing miRNA by targeting PLK4 in NSCLC.

Higher expression of miR-150-5p promotes tumorigenesis by suppressing LKB1 in non-small cell lung cancer

Lung cancer is one of the most malignant tumors that can form in the human. MicroRNAs (MiRNAs) play significant role in tumor progression. Human lung cancer tissues and cell lines were used to determine miR-150-5p respectively, and Liver Kinase B1 (LKB1) expression using quantitative real-time PCR (qRT-PCR). The data analysis website Kaplan-Meier Plotter (database obtained from The Cancer Genome Atlas) was used to perform a survival analysis with LKB1 levels. Using the appropriate assays, the function of miR-150-5p was also detected in cellular proliferation, migration and cell apoptosis as well as cell cycle. Results revealed that miR-150-5p was upregulated in non-small cell lung cancer (NSCLC) tissue and cell lines. In NSCLC, miR-150-5p promoted cellular proliferation and migration, but decreased cellular apoptosis. Conversely, miR-150-5p inhibition suppressed cellular growth. These results further revealed a network of cellular signaling for miR-150-5p to target LKB1. Ectopic expression of LKB1 can mitigate the tumor-promoting function of miR-150-5p. Collectively, these results indicated that miR-150-5p may promote lung cancer by inhibiting the suppressor gene LKB1 in NSCLC.

LncRNA FOXD3-AS1 promoted chemo-resistance of NSCLC cells via directly acting on miR-127-3p/MDM2 axis

Background

This study aims to investigate the mechanism underlying the high level of long non-coding RNA FOXD3-AS1 in cisplatin-resistant NSCLC cells.

Methods

Cisplatin-resistant cells were generated from A549 cells. CCK-8 were used to evaluate cell proliferation. The FOXD3-AS1, miR-127-3p, MDM2 and MRP1 mRNA expression levels were confirmed by qRT-PCR. Protein levels of MDM2 and MRP1 were determined by western blot assay. Luciferase reporter and RNA pull-down assays were evaluated the relationship between miR-127-3p and FOXD3-AS1/MDM2. In vivo tumor growth was evaluated in a xenograft nude mice model.

Results

FOXD3-AS1 was up-regulated in cisplatin-resistant NSCLC cells (A549/DDP and H1299/DDP cells) in comparison with their parental cell lines. Overexpression of FOXD3-AS1 promoted cisplatin-resistance in A549 and H1299 cells; while FOXD3-AS1 knockdown sensitized A549/DDP and H1299/DDP cells to cisplatin treatment. FOXD3-AS1 regulated miR-127-3p expression by acting as a competing endogenous RNA, and miR-127-3p repressed MDM2 expression via targeting the 3'UTR. MiR-127-3p overexpression and MDM2 knockdown both increased the chemo-sensitivity in A549/DDP cells; while miR-127-3p knockdown and MDM2 overexpression both promoted chemoresistance in A549 cells. Further rescue experiments revealed that miR-127-3p knockdown or MDM2 overexpression counteracted the suppressive effects of FOXD3-AS1 knockdown on chemo-resistance and MRP1 expression in A549/DDP cells. In vivo studies showed that FOXD3-AS1 knockdown potentiated the antitumor effects of cisplatin treatment. Inspection of clinical samples showed the upregulation of FOXD3-AS1 and MDM2, and down-regulation of miR-127-3p in NSCLC tissues compared to normal adjacent tissues.

Conclusion

In conclusion, our results suggest that LncRNA FOXD3-AS1 promotes chemo-resistance of NSCLC cells via directly acting on miR-127-3p/MDM2 axis. Our findings may provide novel perspectives for the treatment of NSCLC in patients resistant to chemotherapy.

The microRNA-130a-5p/RUNX2/STK32A network modulates tumor invasive and metastatic potential in non-small cell lung cancer

Background

Non-small cell lung cancer (NSCLC) remains a huge health burden for human health and life worldwide. Our study here was to illuminate the relevance of microRNA-130a-5p (miR-130a-5p) on growth and epithelial mesenchymal transition (EMT) in NSCLC cells along with metastasis in vivo, and to explore the underlying mechanism.

Methods

RT-qPCR was carried out for miR-130a-5p expression determination in NSCLC cells and tissue samples. Dual-luciferase reporter gene assay, RT-qPCR and western blot were carried out to study the potential targets of miR-130a-5p. Effects of miR-130a-5p, runt-related transcription factor 2 (RUNX2) and encoding serine/threonine kinase 32A (STK32A) on NSCLC proliferation, migration, invasion as well as EMT processes were assessed by cell counting kits-8, colony formation, Transwell and western blot assays.

Results

miR-130a-5p was diminished in NSCLC tissues and cells versus their counterparts. miR-130a-5p exerted its repressive role in NSCLC by curtailing cell viability, migration, invasion as well as EMT, while facilitating apoptosis. miR-130a-5p directly targeted RUNX2, a transcription factor, and conversely regulated its expression. RUNX2 was found to interact with STK32A to promote its expression. Following the validation of the supporting role of STK32A in NSCLC cells and NF-κB p65 phosphorylation, RUNX2 overexpression was monitored to reverse miR-130a-5p-inhibited NSCLC tumor volume and weight through enhancing STK32A expression in vivo.

Conclusions

miR-130a-5p diminished the growth and EMT of NSCLC cells by regulating the RUNX2/STK32A/NF-κB p65 axis, offering possible targets for the treatment for NSCLC.

miR-410 induces both epithelial-mesenchymal transition and radioresistance through activation of the PI3K/mTOR pathway in non-small cell lung cancer

Radiotherapy remains one of the major treatments for non-small cell lung cancer (NSCLC) patients; whereas intrinsic or acquired radioresistance limits its efficacy. Nevertheless, most studies so far have only focused on acquired resistance. The exact mechanisms of intrinsic radioresistance in NSCLC are still unclear. A few studies have suggested that epithelial–mesenchymal transition (EMT) is associated with radioresistance in NSCLC. However, little is known about whether the abnormal expression of specific microRNAs induces both EMT and radioresistance. We previously found that miR-410 has multiple roles as an oncomiRNA in NSCLC. In this study, we revealed that miR-410 overexpression promoted EMT and radioresistance, accompanied by enhanced DNA damage repair both in vitro and in vivo. Conversely, knockdown of miR-410 showed the opposite effects. We further demonstrated that PTEN was a direct target of miR-410 by using bioinformatic tools and dual-luciferase reporter assays, and the miR-410-induced EMT and radioresistance were reversed by PI3K, Akt, and mTOR inhibitors or by restoring the expression of PTEN in NSCLC cells. In addition, we preliminarily found that the expression of miR-410 was positively correlated with EMT and negatively associated with the expression of PTEN in NSCLC specimens. In summary, these results demonstrated that miR-410 is an important regulator on enhancing both NSCLC EMT and radioresistance by targeting the PTEN/PI3K/mTOR axis. The findings suggest that miR-410-induced EMT might significantly contribute to the enhanced radioresistance. Therefore, miR-410 may serve as a potential biomarker or therapeutic target for NSCLC radiotherapy.

MiR-182-5p inhibits colon cancer tumorigenesis, angiogenesis, and lymphangiogenesis by directly downregulating VEGF-C

MicroRNAs (miRNAs) are gene modulators essential for biological processes. However, the precise functions of miRNAs in growth and development of colon cancer are still elusive. To clarify their role, here we analyzed a miRNA microarray of colon cancer. MiR-182-5p was found markedly downregulated in colon cancer tissues and cells, and strongly correlated with pathological stage, differentiation, and lymphatic metastasis. In vitro, miR-182-5p overexpression repressed colon cancer cell proliferation, colony formation, migration, and invasion, and triggered G1 arrest and apoptosis. MiR-182-5p overexpression also downregulated vascular endothelial growth factor (VEGF)-C and inhibited the activity of a luciferase reporter containing the VEGF-C 3'-untranslated region. Moreover, miR-182-5p overexpression in colon cancer cells and human umbilical vein endothelial cells (HUVECs) downregulated VEGF-A as well as VEGF receptor (VEGFR)-2 and VEGFR-3, thereby inhibiting the phosphorylation of ERK and AKT. In vivo, miR-182-5p overexpression strikingly suppressed oncogenicity of SW620 cells as well as angiogenesis and lymphangiogenesis of xenograft tumors in nude mice. These data indicate that miR-182-5p regulates colon cancer tumorigenesis partially through modulating angiogenesis and lymphangiogenesis by targeting VEGF-C, and inhibiting ERK and AKT signaling pathways.

microRNA-454 promotes liver tumor-initiating cell expansion by regulating SOCS6

Tumor-initiating cells (T-ICs) are involved in the tumorigenesis, progression, drug resistance and recurrence of hepatocellular carcinoma (HCC). However, the underlying mechanism for the propagation of liver T-ICs remains unclear. Herein, we find that miR-454 is upregulated in liver T-ICs and has an important function in liver T-ICs. Functional studies have revealed that knockdown of miR-454 inhibits liver T-IC self-renewal and tumorigenesis. Conversely, forced miR-454 expression promotes liver T-IC self-renewal and tumorigenesis. Mechanistically, we found that miR-454 downregulates SOCS6 expression in liver T-ICs. The correlation between miR-454 and SOCS6 is validated in human HCC tissues. Furthermore, HCC cells that overexpress miR-454 are resistant to sorafenib treatment. Analysis of patient-derived xenografts (PDXs) further demonstrates that miR-454 may predict sorafenib benefits in HCC patients. In conclusion, our findings reveal the crucial role of miR-454 in liver T-IC expansion and sorafenib response.

miR-212-5p exerts tumor promoter function by regulating the Id3/PI3K/Akt axis in lung adenocarcinoma cells

microRNAs may function as oncogenes or tumor suppressor genes that play crucial roles in human carcinogenesis and cancer development. Growing evidence revealed that the tumor suppressor Id3 is involved in tumor progression, carcinogenesis, and the tumor microenvironment. We identified miR-212-5p as a negative posttranscriptional modulator of Id3. Dual luciferase reporter assay was used to verify that Id3 is a direct target gene of miR-212-5p. Id3 was lowly expressed and miR-212-5p was highly expressed in non-small-cell lung cancer (NSCLC) tissues and cells. In addition, we found that NSCLC patients having a higher level of miR-212-5p expression had a shorter survival time. Besides this, miR-212-5p could directly target Id3 and reduce its expression. miR-212-5p overexpression significantly accelerated cell proliferation, migration, and invasion by reversing the effects of Id3. Id3 overexpression by silencing miR-212-5p expression suppressed phosphatidylinositol 3 kinase (PI3K)/Akt activity and consequently promoted apoptosis and inhibited cell proliferation in lung cancer cells. Consistent with the in vitro results, a xenograft mouse model was used to validate the fact that miR-212-5p could promote tumorigenesis by targeting Id3 and activate the PI3K/Akt pathway in vivo as well. Taken together, the present results indicated that miR-212-5p may be involved in progression of NSCLC through the PI3K/Akt signaling pathway by targeting Id3.

LncRNA SNHG16 promotes non-small cell lung cancer development through regulating EphA2 expression by sponging miR-520a-3p

BACKGROUND

Recent evidence has found that lncRNA small nucleolar RNA host gene 16 (SNHG16) was associated with cell carcinogenesis in NSCLC. Here, we further investigated the precise functions and mechanisms of SNHG16 in NSCLC progression.

METHODS

The expression of SNHG16, microRNA (miR)-520a-3p and EPH Receptor A2 (EphA2) was measured using quantitative real-time polymerase chain reaction and western blot, respectively. Cell proliferation was determined using 3-(4, 5)-dimethylthiahiazo (-z-y1)-3, 5-di-phenytetrazoliumromide (MTT) assay. The migrated and invaded cells were measured by Transwell assay. Flow cytometry was used to detect apoptotic cells. The interaction between miR-520a-3p and SNHG16 or EphA2 was confirmed using a dual-luciferase reporter assay.

RESULTS

We found that SNHG16 was upregulated in NSCLC tissues and cell lines, knockdown of SNHG16 inhibited cell proliferation, migration, invasion and induced apoptosis in vitro as well as suppressed tumor growth in vivo. MiR-520a-3p directly bound to SNHG16 and miR-520a-3p, and SNHG16 acted as a ceRNA in regulating EphA2 through competitively binding to miR-520a-3p. Additionally, rescue assay exhibited the anticancer activity mediated by SNHG16 knockdown on NSCLC could be reversed by miR-520a-3p inhibition or EphA2 overexpression.

CONCLUSION

SNHG16 promoted NSCLC development by regulating the miR-520a-3p/EphA2 axis, suggesting novel insights for the pathogenesis of NSCLC and new potential therapeutic targets for the treatment of NSCLC.

KEY POINTS

Knockdown of SNHG16 inhibited NSCLC cell proliferation, migration, invasion and induced apoptosis in vitro as well as suppressed tumor growth in vivo. SNHG16 directly interacted with miR-520a-3p. EphA2 was a target of miR-520a-3p. SNHG16 could regulate the expression of EphA2 by binding to miR-520a-3p. SNHG16 promoted NSCLC development by regulating the miR-520a-3p/EphA2 axis.

Diagnostic and theranostic microRNAs in the pathogenesis of atherosclerosis

MicroRNAs (miRNAs) are a group of small single strand and noncoding RNAs that regulate several physiological and molecular signalling pathways. Alterations of miRNA expression profiles may be involved with pathophysiological processes underlying the development of atherosclerosis and cardiovascular diseases, including changes in the functions of the endothelial cells and vascular smooth muscle cells, such as cell proliferation, migration and inflammation, which are involved in angiogenesis, macrophage function and foam cell formation. Thus, miRNAs can be considered to have a crucial role in the progression, modulation and regulation of every stage of atherosclerosis. Such potential biomarkers will enable us to predict therapeutic response and prognosis of cardiovascular diseases and adopt effective preclinical and clinical treatment strategies. In the present review article, the current data regarding the role of miRNAs in atherosclerosis were summarized and the potential miRNAs as prognostic, diagnostic and theranostic biomarkers in preclinical and clinical studies were further discussed. The highlights of this review are expected to present opportunities for future research of clinical therapeutic approaches in vascular diseases resulting from atherosclerosis with an emphasis on miRNAs.

MicroRNA-130a enhances the killing ability of natural killer cells against non-small cell lung cancer cells by targeting signal transducers and activators of transcription 3

Non-small cell lung cancer (NSCLC) is a serious threat for human health and life. Natural killer (NK) cell-based immunotherapy is a promising anti-tumor strategy in various cancers including NSCLC. Emerging microRNA (miRNA) has been identified as vital regulators in NK cell-mediated immunosurveillance process. MicroRNA-130a (miR-130a) level and signal transducers and activators of transcription 3 (STAT3) mRNA level was measured by RT-qPCR assay. STAT3 protein level was determined by western blot assay. IFN-γ and TNF-α secretion was examined by corresponding ELISA kits. NK cell cytotoxicity was assessed by lactate dehydrogenase (LDH) assay. The interaction between miR-130a and STAT3 was explored by bioinformatics analysis, luciferase reporter assay and RNA immunoprecipitation (RIP) assay. We found that MiR-130a level was notably reduced and STAT3 expression was dramatically increased in primary NK cells isolated from NSCLC patients. But, miR-130a was highly expressed and STAT3 was low expressed in IL-2-activated NK-92 cells. Functional analysis revealed that miR-130a overexpression potentiated killing ability of NK cells against A549 cells. Further investigations unveiled that STAT3 was a target of miR-130a and STAT3 overexpression abrogated miR-130a-induced improvement in killing activity of NK cells against NSCLC cells. In conclusion, MiR-130a improved the killing capacity of NK cells against NSCLC cells by targeting STAT3, laying a foundation for future studies on the roles and molecular basis of miR-130a in NK cell-based immunotherapy against various cancers.

Current Landscape of Epigenetics in Lung Cancer: Focus on the Mechanism and Application

Lung cancer is the leading cause of cancer-related mortality worldwide. Tumorigenesis involves a multistep process resulting from the interactions of genetic, epigenetic, and environmental factors. Genome-wide association studies and sequencing studies have identified many epigenetic alterations associated with the development of lung cancer. Epigenetic mechanisms, mainly including DNA methylation, histone modification, and noncoding RNAs (ncRNAs), are heritable and reversible modifications that are involved in some important biological processes and affect cancer hallmarks. We summarize the major epigenetic modifications in lung cancer, focusing on DNA methylation and ncRNAs, their roles in tumorigenesis, and their effects on key signaling pathways. In addition, we describe the clinical application of epigenetic biomarkers in the early diagnosis, prognosis prediction, and oncotherapy of lung cancer. Understanding the epigenetic regulation mechanism of lung cancer can provide a new explanation for tumorigenesis and a new target for the precise treatment of lung cancer.

MicroRNA-147b suppresses the proliferation and invasion of non-small-cell lung cancer cells through downregulation of Wnt/β-catenin signalling via targeting of RPS15A

Deregulation of microRNAs (miRNAs) leads to malignant growth and aggressive invasion during cancer occurrence and progression. miR-147b has emerged as one of the cancer-related miRNAs that are dysregulated in multiple cancers. Yet, the relevance of miR-147b in non-small-cell lung cancer (NSCLC) remains unclear. In the present study, we aimed to report the biological function and signalling pathways mediated by miR-147b in NSCLC. Our results demonstrate that miR-147b expression is significantly downregulated in NSCLC tissues and cell lines. Overexpression of miR-147b decreased the proliferative ability, colony-forming capability, and invasive potential of NSCLC cells. Notably, our study identified ribosomal protein S15A (RPS15A), an oncogene in NSCLC, as a target gene of miR-147b. Our results showed that miR-147b negatively modulates RPS15A expression in NSCLC cells. An inverse correlation between miR-147b and RPS15A was evidenced in NSCLC specimens. Moreover, miR-147b overexpression downregulated the activation of Wnt/β-catenin signalling via targeting of RPS15A. Overexpression of RPS15A partially reversed the miR-147b-mediated antitumour effect in NSCLC cells. Collectively, these findings reveal that miR-147b restricts the proliferation and invasion of NSCLC cells by inhibiting RPS15A-induced Wnt/β-catenin signalling and suggest that the miR-147b/RPS15A/Wnt/β-catenin axis is an important regulatory mechanism for malignant progression of NSCLC.

MiRNA therapeutics based on logic circuits of biological pathways

BACKGROUND

In silico experiments, with the aid of computer simulation, speed up the process of in vitro or in vivo experiments. Cancer therapy design is often based on signalling pathway. MicroRNAs (miRNA) are small non-coding RNA molecules. In several kinds of diseases, including cancer, hepatitis and cardiovascular diseases, they are often deregulated, acting as oncogenes or tumor suppressors. miRNA therapeutics is based on two main kinds of molecules injection: miRNA mimics, which consists of injection of molecules that mimic the targeted miRNA, and antagomiR, which consists of injection of molecules inhibiting the targeted miRNA. Nowadays, the research is focused on miRNA therapeutics. This paper addresses cancer related signalling pathways to investigate miRNA therapeutics.

RESULTS

In order to prove our approach, we present two different case studies: non-small cell lung cancer and melanoma. KEGG signalling pathways are modelled by a digital circuit. A logic value of 1 is linked to the expression of the corresponding gene. A logic value of 0 is linked to the absence (not expressed) gene. All possible relationships provided by a signalling pathway are modelled by logic gates. Mutations, derived according to the literature, are introduced and modelled as well. The modelling approach and analysis are widely discussed within the paper. MiRNA therapeutics is investigated by the digital circuit analysis. The most effective miRNA and combination of miRNAs, in terms of reduction of pathogenic conditions, are obtained. A discussion of obtained results in comparison with literature data is provided. Results are confirmed by existing data.

CONCLUSIONS

The proposed study is based on drug discovery and miRNA therapeutics and uses a digital circuit simulation of a cancer pathway. Using this simulation, the most effective combination of drugs and miRNAs for mutated cancer therapy design are obtained and these results were validated by the literature. The proposed modelling and analysis approach can be applied to each human disease, starting from the corresponding signalling pathway.

Research progress on the relationship between lung cancer drug-resistance and microRNAs

Lung cancer, a malignant tumor with the highest death rate of cancer, seriously endangers human health. And its pathogenesis and mechanism of drug resistance has been partially clarified, especially for the signal pathway of epidermal growth factor receptor (EGFR). The targeting therapy of EGFR signaling pathway in non-small cell lung cancer (NSCLC) has achieved a certain effect, but the two mutation of EGFR and other mechanisms of lung cancer resistance still greatly reduce the therapeutic effect of chemotherapy on it. MicroRNA is an endogenous non coding RNA, which has a regulatory function after transcriptional level. Recent studies on the mechanism of lung cancer resistance have found that a variety of microRNAs are related to the mechanism of lung cancer drug-resistance. They can regulate lung cancer resistance by participating in signal pathways, drug resistance genes and cell apoptosis, thus affecting the sensitivity of cancer cells to drugs. Therefore, microRNAs can be used as a specific target for the treatment of lung cancer and plays a vital role in the early diagnosis, prognosis and treatment of lung cancer. This article reviews the mechanisms of lung cancer resistance and its relationship with microRNAs.

miR-1305 Inhibits The Progression Of Non-Small Cell Lung Cancer By Regulating MDM2

Background

Increasing evidence has suggested the critical implication of microRNAs (miRNAs) in the initiation and progression of non-small cell lung cancer (NSCLC). Previous studies have shown the tumor-suppressive function of miR-1305 in cancer; however, the role of miR-1305 in NSCLC has not been fully understood.

Methods

The expression of miR-1305 in NSCLC was detected by RT-qPCR. The influence of miR-1305 on the growth of NSCLC cells was determined via Cell Counting Kit 8 (CCK-8), colony formation and FACS analysis. The targets of miR-1305 were predicted with the miRDB database. Luciferase reporter assay was performed to investigate the binding between miR-1305 and 3ʹ-UTR of MDM2. Western blot was applied to check the expression of MDM2 with miR-1305.

Results

Here, we found that miR-1305 was down-regulated in NSCLC tissues and cell lines. Decreased miR-1305 was significantly correlated with the metastasis and poor prognostics of NSCLC patients. Overexpression of miR-1305 inhibited the proliferation and migration and promoted the apoptosis of NSCLC cells. Bioinformatics and luciferase assay uncovered that the mouse/murine double minute 2 (MDM2) was a target of miR-1305. miR-1305 bound the 3ʹ-untranslated region (UTR) of MDM2 and decreased the expression of MDM2 in NSCLC cells. As MDM2 was a negative regulator of p53, decreased MDM2 by miR-1305 up-regulated the abundance of p53 in NSCLC cells. Restoration of MDM2 markedly attenuated the suppressive role of miR-1305 in the proliferation and migration of NSCLC cells.

Conclusion

The findings provided novel mechanism of miR-1305/MDM2 signaling in regulating the progression of NSCLC, suggesting miR-1305 as a promising target for the treatment of NSCLC.