MiR-181a-5p inhibits cell proliferation and migration by targeting Kras in non-small cell lung cancer A549 cells

Non-coding RNAs and exosomal non-coding RNAs in lung cancer: insights into their functions

Lung cancer is the second most common form of cancer worldwide Research points to the pivotal role of non-coding RNAs (ncRNAs) in controlling and managing the pathology by controlling essential pathways. ncRNAs have all been identified as being either up- or downregulated among individuals suffering from lung cancer thus hinting that they may play a role in either promoting or suppressing the spread of the disease. Several ncRNAs could be effective non-invasive biomarkers to diagnose or even serve as effective treatment options for those with lung cancer, and several molecules have emerged as potential targets of interest. Given that ncRNAs are contained in exosomes and are implicated in the development and progression of the malady. Herein, we have summarized the role of ncRNAs in lung cancer. Moreover, we highlight the role of exosomal ncRNAs in lung cancer.

Sex differences in the tumor promoting effects of tobacco smoke in a cRaf transgenic lung cancer disease model

Tobacco smoke (TS) is the leading cause for lung cancer (LC), and female smokers are at a greater risk for LC. Yet, the underlying causes are unknown. We performed whole genome scans in TS exposed wild type and histologically characterized tumor lesions of cRaf transgenic mice. We constructed miRNA-gene and transcription factor-miRNA/gene regulatory networks and determined sex-specific gene regulations by evaluating hormone receptor activities. We validated the findings from TS exposed cRaf mice in a large cohort of smoking and never-smoking LC patients. When compared to males, TS prompted a sevenfold increase in tumor multiplicity in cRaf females. Genome-wide scans of tumor lesions identified 161 and 53 genes and miRNAs, which code for EGFR/MAPK signaling, cell proliferation, oncomirs and oncogenes, and 50% of DEGs code for immune response and tumor evasion. Outstandingly, in transgenic males, TS elicited upregulation of 20 tumor suppressors, some of which are the targets of the androgen and estrogen receptor. Conversely, in females, 18 tumor suppressors were downregulated, and five were specifically repressed by the estrogen receptor. We found TS to perturb the circadian clock in a sex-specific manner and identified a female-specific regulatory loop that consisted of the estrogen receptor, miR-22-3p and circadian genes to support LC growth. Finally, we confirmed sex-dependent tumor promoting effects of TS in a large cohort of LC patients. Our study highlights the sex-dependent genomic responses to TS and the interplay of circadian clock genes and hormone receptors in the regulation of oncogenes and oncomirs in LC growth.

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.

Role of miR‑181a‑5p in cancer (Review)

MicroRNAs (miRNAs) are non‑coding RNAs (ncRNAs) that can post‑transcriptionally suppress targeted genes. Dysregulated miRNAs are associated with a variety of diseases. MiR‑181a‑5p is a conserved miRNA with the ability to regulate pathological processes, such as angiogenesis, inflammatory response and obesity. Numerous studies have demonstrated that miR‑181a‑5p exerts regulatory influence on cancer development and progression, acting as an oncomiR or tumor inhibitor in various cancer types by impacting multiple hallmarks of tumor. Generally, miR‑181a‑5p binds to target RNA sequences with partial complementarity, resulting in suppression of the targeted genes of miR‑181a‑5p. However, the precise role of miR‑181a‑5p in cancer remains incompletely understood. The present review aims to provide a comprehensive summary of recent research on miR‑181a‑5p, focusing on its involvement in different types of cancer and its potential as a diagnostic and prognostic biomarker, as well as its function in chemoresistance.

Double-edged sword role of miRNA-633 and miRNA-181 in human cancers

Understanding the function and mode of operation of microRNAs (miRNAs) in cancer is of growing interest. The short non-coding RNAs known as miRNAs, which target mRNA in multicellular organisms, are described as controlling essential cellular processes. The miR-181 family and miR-633 are well-known miRNAs that play a key role in the development and metastasis of tumor cells. They may facilitate either tumor-suppressive or oncogenic function in malignant cells, according to mounting evidence. Metastatic cells that are closely linked to cancer cell migration, invasion, and angiogenesis can be identified by abnormal levels of miR-181 and miR-633. Numerous studies have demonstrated their capacity to control drug resistance, cell growth, apoptosis, and the epithelial-mesenchymal transition (EMT) and metastasis process. Interestingly, the levels of miR-181 and miR-633 and their potential target genes in the basic cellular process can vary depending on the type of cancer cells and their gene expression profile. Such miRNAs' interactions with other non-coding RNAs such as long non-coding RNAs and circular RNAs can influence tumor behaviors. Herein, we concentrated on the multifaceted roles of miR-181 and miR-633 and potential targets in human tumorigenesis, ranging from cell growth and metastasis to drug resistance.

Recent Advances in Extracellular Vesicles in Amyotrophic Lateral Sclerosis and Emergent Perspectives

Amyotrophic lateral sclerosis (ALS) is a severe and incurable neurodegenerative disease characterized by the progressive death of motor neurons, leading to paralysis and death. It is a rare disease characterized by high patient-to-patient heterogeneity, which makes its study arduous and complex. Extracellular vesicles (EVs) have emerged as important players in the development of ALS. Thus, ALS phenotype-expressing cells can spread their abnormal bioactive cargo through the secretion of EVs, even in distant tissues. Importantly, owing to their nature and composition, EVs' formation and cargo can be exploited for better comprehension of this elusive disease and identification of novel biomarkers, as well as for potential therapeutic applications, such as those based on stem cell-derived exosomes. This review highlights recent advances in the identification of the role of EVs in ALS etiopathology and how EVs can be promising new therapeutic strategies.

The role of selected non-coding RNAs in the biology of non-small cell lung cancer

Lung cancer is the second most frequently diagnosed cancer worldwide and a leading cause of cancer-related deaths. Non-small cell lung carcinoma (NSCLC) represents 85% of all cases. Accumulating evidence highlights the outstanding role of non-coding RNA (ncRNA) in regulating the tumorigenesis process by modulating crucial signaling pathways. Micro RNA (miRNA), long non-coding RNA (lncRNA) and circular RNA (circRNA) are either up- or downregulated in lung cancer patients and can promote or suppress the progression of the disease. These molecules interact with messenger RNA (mRNA) and with each other to regulate gene expression and stimulate proto-oncogenes or silence tumor suppressors. NcRNAs provide a new strategy to diagnose or treat lung cancer patients and multiple molecules have already been identified as potential biomarkers or therapeutic targets. The aim of this review is to summarize the current evidence on the roles of miRNA, lncRNA and circRNA in NSCLC biology and present their clinical potential.

Immunoregulatory framework and the role of miRNA in the pathogenesis of NSCLC - A systematic review

With a 5-year survival rate of only 15%, non-small cell lung cancer (NSCLC), the most common kind of lung carcinoma and the cause of millions of deaths annually, has drawn attention. Numerous variables, such as disrupted signaling caused by somatic mutations in the EGFR-mediated RAS/RAF/MAPK, PI3K/AKT, JAK/STAT signaling cascade, supports tumour survival in one way or another. Here, the tumour microenvironment significantly contributes to the development of cancer by thwarting the immune response. MicroRNAs (miRNAs) are critical regulators of gene expression that can function as oncogenes or oncosuppressors. They have a major influence on the occurrence and prognosis of NSCLC. Though, a myriad number of therapies are available and many are being clinically tested, still the drug resistance, its adverse effect and toxicity leading towards fatality cannot be ruled out. In this review, we tried to ascertain the missing links in between perturbed EGFR signaling, miRNAs favouring tumorigenesis and the autophagy mechanism. While connecting all the aforementioned points multiple associations were set, which can be targeted in order to combat NSCLC. Here, we tried illuminating designing synthetically engineered circuits with the toggle switches that might lay a prototype for better therapeutic paradigm.

Free fatty acid-induced miR-181a-5p stimulates apoptosis by targeting XIAP and Bcl2 in hepatic cells

AIMS

Non-alcoholic fatty liver disease is one of the major health concerns in the World. The dietary free fatty acids (FFAs) affect the metabolic status of the hepatocytes by modulating cellular pathways. In this study, we showed that free fatty acids stimulate apoptosis by upregulating miR-181a-5p expression, which in turn targets XIAP and Bcl2.

METHODS

Huh7 cells were incubated with FFAs for 72 h and the expression of XIAP, Bcl2, bax, pAkt, Akt, PTEN and β-actin were determined by Western blots, and miR-181a-5p expression was determined using real-time RT-PCR. The Huh7 cells were transfected with either miR-181a-5p pre-miRs or anti-miR-181a-5p and the regulation of apoptosis and proliferation was studied. Three groups of C57BL/6 mice (n = 6 per group) were fed with standard diet, CSAA or CDAA diet for 6, 18, 32 and 54 weeks. Total protein and RNA were isolated from the liver tissues and used for Western blots and real-time RT-PCR respectively.

KEY FINDINGS

FFAs inhibited Akt phosphorylation, expression of XIAP and Bcl2, while upregulating the expression of PTEN, bax, and miR-181a-5p in Huh7 cells. Similar results were observed when the Huh7 cells were transfected with miR-181a-5p premiRs, while these changes were reversed in anti-miR-181a-5p-transfected, FFA-treated Huh7 cells. The CDAA-fed mice showed a significant inhibition of Akt phosphorylation, XIAP and Bcl2, whereas PTEN and bax expression were upregulated. The expression of miR-181a-5p was also significantly higher in CDAA-fed mice.

SIGNIFICANCE

These findings showed that free fatty acids induced apoptosis via upregulating miR-181a-5p in hepatic cells.

Efficacy of Sirna-Loaded Nanoparticles in the Treatment of k-ras Mutant Lung Cancer in vitro

AIM

To design and develop K-RAS silencing small interfering RNA (siRNA)-loaded poly (D, L-lactic-co-glycolic acid) nanoparticles and evaluate their efficacy in the treatment of K-RAS mutant lung cancer.

METHODS

The nanoparticles prepared by the double emulsion solvent evaporation method were characterized by TEM, FTIR and XPS analyzes and evaluated in vitro by XTT, PCR, ELISA, and Western-Blot. Metabolomic analyzes were performed to evaluate the changes in metabolic profiles of the cells after nanoparticles treatment.

RESULTS

The nanoparticles were obtained with a particle size less than 250 nm, a polydispersity index around 0.1, a surface charge of (-12) - (+14) mV, and 80% of the siRNA encapsulation. The nanoparticles didn't affect cell viability of the cells after 72 hours. In cancer cells, KRAS expression was decreased by up to 50%, protein levels were decreased by more than 90%.

CONCLUSION

The formulated siRNA delivery nanoparticles can be promising treatment in lung cancer.

Hsa-miR-181a-5p, hsa-miR-182-5p, and hsa-miR-26a-5p as potential biomarkers for BCR-ABL1 among adult chronic myeloid leukemia treated with tyrosine kinase inhibitors at the molecular response

BACKGROUND

Tyrosine kinase inhibitors (TKIs) as first-line therapy for Chronic Myeloid Leukemia (CML) show a high success rate. However, a low number of patients with long-term treatment-free remission (TFR) were observed. Molecular relapse after imatinib discontinuation occurred at 50% at 24 months, with 80% occurrence within the first 6 months. One of the reasons for relapse is untimely TKIs discontinuation caused by large errors from estimates at very low-level or undetectable disease, thus warranting new biomarkers for CML.

METHODS

Next Generation Sequencing (NGS) was used to identify microRNAs (miRNAs) at the molecular response in CML adult patients receiving TKIs treatment. A total of 86 samples were collected, 30 from CML patients responsive and 28 from non-responsive to imatinib therapy, and 28 from blood donors. NGS was conducted whereby 18 miRNAs were selected and validated by real-time RT-qPCR in triplicate.

RESULTS

Hsa-miR-181a-5p was expressed significantly (p-value< 0.05) with 2.14 and 2.33-fold down-regulation in both patient groups, respectively meanwhile hsa-miR-182-5p and hsa-miR-26a-5p were significant only in the non-responsive group with 2.08 and 2.39 fold up-regulation. The down-regulation was consistent with decreased amounts of BCR-ABL1 in patients taking TKIs regardless of molecular responses. The up-regulation was consistent with the substantial presence of BCR-ABL1 in CML patients treated with TKIs at the molecular response.

CONCLUSIONS

Therefore, these miRNAs have potential as new therapeutic biomarkers for BCR-ABL1 status in adult CML patients treated with TKIs at molecular responses. These could improve current approaches and require further analysis to look for targets of these miRNAs in CML.

Exosomes from M1‐polarized macrophages promote apoptosis in lung adenocarcinoma via the miR‐181a‐5p/ETS1/STK16 axis

Serine/threonine kinase 16 (STK16) is crucial in on regulating tumor cell proliferation, apoptosis, and prognosis. Activated M1 macrophages regulate lung adenocarcinoma (LUAD) growth by releasing exosomes. This study aims to investigate the role of STK16 and then focus on the possible mechanisms through which exosomes derived from M1 macrophages play their roles in LUAD cells by targeting STK16. Clinical LUAD samples were used to evaluate the expression of STK16 and its association with prognosis. Exosomes were isolated from M0 and M1 macrophages by ultracentrifugation and were then identified by electron microscopy and western blotting. In vitro gain‐ and loss‐of‐function experiments with LUAD cells were performed to elucidate the functions of miR‐181a‐5p, ETS1, and STK16, and mouse xenograft models were used to verify the function of STK16 in vivo. Western blotting, quantitative real‐time PCR, CCK‐8 assay, cell apoptosis, immunohistochemistry staining, luciferase assay, ChIP assay, and bioinformatics analysis were performed to reveal the underlying mechanisms. High expression of STK16 was observed in LUAD tissues and cells, and higher expression of STK16 was associated with worse prognosis. Silencing STK16 expression inhibited cell proliferation and promoted apoptosis via the AKT1 pathway. Exosomes from M1 macrophages inhibited viability and promoted apoptosis by inhibiting STK16. Moreover, miR‐181a‐5p is the functional molecule in M1 macrophage‐derived exosomes and plays a vital role in inhibiting cell proliferation and promoting apoptosis by targeting ETS1 and STK16. Hence, exosomes derived from M1 macrophages were capable of inhibiting viability and promoting apoptosis in LUAD via the miR‐181a‐5p/ETS1/STK16 axis.

microRNA-181a-5p impedes the proliferation, migration, and invasion of retinoblastoma cells by targeting the NRAS proto-oncogene

OBJECTIVES

Accumulating research have reported that microRNAs (miRNAs) play important roles in Retinoblastoma (RB). Nonetheless, the function and underlying mechanism of miR-181a-5p in RB remain ambiguous.

METHODS

The relative expression levels of miR-181a-5p and NRAS mRNA were detected by quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR). RB cell proliferation was measured using the Cell Counting Kit-8 (CCK-8) and 5'-Bromo-2'-deoxyuridine (BrdU) assays. Transwell assays and flow cytometry were performed to detect the migration, invasion, and apoptosis of RB cells. The interaction between miR-181a-5p and NRAS was explored using luciferase experiments, western blotting, and qRT-PCR.

RESULTS

miR-181a-5p expression was found to be decreased in RB tissues and cell lines, and its expression was correlated with unfavorable pathological features of the patients. In vitro experiments revealed that miR-181a-5p reduced RB cell proliferation, migration, and invasion while enhancing apoptosis. Further research confirmed that NRAS is a direct target of miR-181a-5p. miR-181a-5p inhibited NRAS expression at both the mRNA and protein levels. Co-transfection of pcDNA-NRAS or NRAS small interfering RNA (siRNA) reversed the effects of miR-181a-5p mimics or miR-181a-5p inhibitors on RB cells.

CONCLUSION

miR-181a-5p was significantly downregulated during the development of RB, and it suppressed the malignant behaviors of RB cells by targeting NRAS.

MiR-181a-5p facilitates proliferation, invasion, and glycolysis of breast cancer through NDRG2-mediated activation of PTEN/AKT pathway

Dysregulation of microRNAs (miRNAs) is associated with the occurrence and development of breast cancer. In this research, we explored the involvement of miR-181a-5p in the progression of breast cancer and investigated potential molecular mechanisms. Firstly, the miR-181a-5p and N-myc downstream-regulated gene (NDRG) 2 expression was detected by real-time quantitative polymerase chain reaction. Cellular processes were assessed using Cell Counting Kit 8, Bromodeoxyuridine, colony formation and transwell assays. HK2, PKM2 and LDHA activities were assessed by ELISA. The combination between miR-181a-5p was assessed by dual-luciferase reporter assay and RNA pull-down assay. The results indicated that miR-181a-5p levels were upregulated and NDRG2 levels were downregulated in breast cancer, leading to poor prognosis. Silencing of miR-181a-5p inhibited cell proliferation, invasion, glycolysis, and xenograft tumor growth, while enhanced miR-181a-5p got the opposite results. Furthermore, NDRG2 acts as a target of miR-181a-5p. Knockout of NDRG2 facilitated biological behaviors and meanwhile enhanced phosphorylation (p)-PTEN and p-AKT levels. Rescue experiments showed that restoring NDRG2 abolished the effects caused by miR-181a-5p in breast cancer cells. In conclusion, miR-181a-5p facilitated tumor progression through NDRG2-induced activation of PTEN/AKT signaling pathway of breast cancer, suggesting that focusing on miR-181a-5p may provide new insight for breast cancer therapy.

Abbreviations Brdu: Bromodeoxyuridine; CCK-8: Cell Counting Kit-8; miRNA: microRNAs; mut: mutant; RT-qPCR: real-time quantitative polymerase chain reaction; UTR: untranslated region; WT: wild-type

Effect of c-fos gene silence on PM2.5-induced miRNA alteration in human bronchial epithelial cells

Human bronchial epithelial (HBE) cells and c-fos-silenced HBE cells were first exposed to fine particulate matter (PM_2.5) and the resulting miRNA sequenced. Thereafter, a weighted gene co-expression network analysis was performed using Cytoscape software to visualize the interactions between identified hub miRNAs and their target genes. Nine differentially expressed miRNAs in hub miRNAs were identified in the different treatment groups, of which miR-25-3p, miR-215-5p, and miR-145-5p were selected for further study. Following qPCR validation, both miR-25-3p and miR-215-5p were found to be significantly up-regulated whilst, miR-145-5p was significantly down-regulated (p < 0.05) in the PM_2.5 group. Furthermore, miR-25-3p and miR-145-5p were also significantly down-regulated in the untreated group of c-fos silenced HBE cells. However, miR-215-5p was significantly down-regulated in both the untreated and PM_2.5-treated groups of c-fos silenced HBE cells. Subsequent analysis of their target genes also illustrated differential gene expression when comparing the treatment groups of the two cell types. The present data indicated that the c-fos gene has an important effect on the miRNA expression profiles and the related signaling pathways in PM_2.5-treated HBE cells. Therefore, each of miR-25-3p, miR-145-5p, and miR-215-5p may potentially provide future research information for additional exploration of a PM_2.5-induced carcinogenesis mechanism.

Association of miRNA 30c, miRNA 181a and miRNA 570 SNPs with Bladder Cancer Risk in North Indian Population: A Pilot Study

miRNA play role in post transcriptional regulation of genes and serves a range of biological functions such as initiation, development, metastasis etc. which are also hallmarks of cancer. Hence, we evaluated miRNA 181a, miRNA 30c and miRNA 570 in bladder cancer risk association among North Indians. miRNA 570 C/G (rs4143815), miRNA 30c A/G (rs928508) and miRNA 181a C/T (rs12537) single nucleotide polymorphisms (SNPs) were genotyped by allelic discrimination TaqMan assay in 100 bladder cancer (BC) patients and 100 healthy controls. No significant difference was found in the genotype frequencies of the candidate SNPs among cases and controls. However, combined effect of miRNA 570-miRNA 30c (CG + AA) p = 0.005, OR = 0.223, 95% CI and miRNA 570-miRNA 181a (CG + CC) p = 0.003, OR = 0.169, 95% CI conferred association with no risk of BC. miRNA 181a C/T (rs12537), miRNA 30c A/G (rs928508) and miRNA 570 C/G (rs4143815) should be further validated in large sample size to be used as a risk predictor for bladder cancer among North Indians.

Profiling and Integrated Analysis of Differentially Expressed Circular RNAs in Plasma Exosomes as Novel Biomarkers for Advanced-Stage Lung Adenocarcinoma

Purpose

Exosomes contain abundant circRNAs and are determined to be involved in the pathogenesis of lung adenocarcinoma (LUAD). Thus, our study aimed to explore new circRNAs in plasma exosomes that could be involved in such pathogenesis.

Patients and Methods

High-throughput sequencing was used in identifying the alterations in exosomal circRNA expression. Gene ontology functional analysis (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed to determine the significant functions and pathways associated with differentially expressed circRNAs. TargetScan and miRanda were used to predict circRNA-targeted microRNAs and mRNAs. CircRNA expression profiles were then validated by quantitative reverse-transcription polymerase chain reaction (qRT-PCR). Wound healing and Transwell assays were performed to determine the roles of has_circ_0102537 in LUAD progression.

Results

We identified six significantly upregulated and 214 significantly downregulated circRNAs. GO and KEGG pathway analysis suggested that the differentially expressed circRNAs are involved in the occurrence and development of LUAD. A circRNA–miRNA–mRNA meshwork was established to predict the potential interactions among these RNAs. The circRNA expression profile was then subjected to qRT-PCR for validation. We identified hsa_circ_0102537 to be downregulated in both LUAD plasma exosomes and tissues. GO, KEGG pathway analysis, circRNA–miRNA–mRNA meshwork, and further experiments suggest that hsa_circ_0102537 could be involved in LUAD progression.

Conclusion

Our study explored a large number of circRNAs that may be involved in the LUAD pathogenesis, thereby supporting the need for further research on both diagnosis biomarkers and the potential intervention therapeutic targets.

The circular RNAs differential expression profiles in the metastasis of salivary adenoid cystic carcinoma cells

In order to reveal circular RNAs (circRNAs) differential expression profiles and investigate the function and mechanism of circRNAs in the metastasis of salivary adenoid cystic carcinoma (SACC), microarray was used to detect differentially expressed circRNAs in SACC-83 and SACC-lung metastasis (LM) cell lines. Up-regulated circRNAs were analyzed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses to further predict their function. Expression of candidate circRNA and microRNA (miRNA) was determined using quantitative real-time polymerase chain reaction (qRT-PCR). Constructed circRNA-miRNA-mRNA co-expression network was based on TargetScan, miRanda databases. Wound healing and transwell assays were completed to examine the effects of hsa_circRNA_001982 and miR-181a-5p on cell migration and invasion. qRT-PCR confirmed hsa_circRNA_092556, hsa_circRNA_101379, and hsa_circRNA_001982 up-regulation in SACC-LM. miR-181a-5p was down-regulated in SACC-LM and correlated with up-regulated hsa_circRNA_001982. Wound healing and transwell assays indicated that silencing hsa_circRNA_001982 inhibited the migration and invasion of the SACC-LM cells. Furthermore, over-expression of hsa_circRNA_001982 promoted the migration and invasion of SACC-83 cells. Interestingly, up-regulation or down-regulation of miR-181a-5p led to the opposite result in wound healing and transwell assays. Overall, differential expression circRNA profiles in SACC-83 and SACC-LM cells may reveal potential targets and a novel mechanism of circRNAs in the metastasis of SACC. Moreover, the interaction of hsa_circRNA_001982/miR-181a-5p is closely related to the metastasis of SACC cells.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Long Noncoding RNA SNHG7 Accelerates Proliferation, Migration and Invasion of Non-Small Cell Lung Cancer Cells by Suppressing miR-181a-5p Through AKT/mTOR Signaling Pathway

Purpose

Non-small cell lung cancer (NSCLC) is a typical epithelial lung cancer with high metastasis, incidence and mortality. In recent years, long noncoding RNA small nucleolar RNA host gene 7 (SNHG7) has been identified as significant regulator in different cancer types, including NSCLC. However, the underlying molecular mechanism of SNHG7 during NSCLC tumorigenesis and progression remains largely unclear.

Methods

SNHG7 and miR-181a-5p expression in NSCLC tumors and cells were detected by qRT-PCR. Cell viability, migration, invasion and apoptosis were evaluated by CCK-8, transwell and flow cytometry assay, respectively. A549 and NCI-H1299 xenograft mice model was constructed by subcutaneously injecting cells stably transfected with sh-SNHG7 and sh-NC. The interaction between SNHG7 and miR-181a-5p was validated by luciferase reporter system, RIP and RNA pull down assay. Protein expression of cleaved caspase 3, proliferating cell nuclear antigen (PCNA), AKT, p-AKT, mammalian target of rapamycin (mTOR) and p-mTOR was analyzed by Western blot.

Results

SNHG7 expression was up-regulated while miR-181a-5p expression was down-regulated in NSCLC tumors, especially those from patients at Phase III+IV, compared with normal tissues. However, SNHG7 depletion attenuated tumor growth in vitro and in vivo. Moreover, miR-181a-5p inhibitor abolished SNHG7 silencing induced inhibition on proliferation, migration and invasion in NSCLC. Subsequently, we found SNHG7 modulated cell progression by targeting miR-181a-5p and activating AKT/mTOR signaling pathway.

Conclusion

SNHG7 accelerates proliferation, migration and invasion of NSCLC by suppressing miR-181a-5p through AKT/mTOR signaling pathway, thus presenting desirable biomarkers for NSCLC therapy.

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.

Targeting Endogenous K-RAS for Degradation through the Affinity-Directed Protein Missile System

K-RAS is known as the most frequently mutated oncogene. However, the development of conventional K-RAS inhibitors has been extremely challenging, with a mutation-specific inhibitor reaching clinical trials only recently. Targeted proteolysis has emerged as a new modality in drug discovery to tackle undruggable targets. Our laboratory has developed a system for targeted proteolysis using peptidic high-affinity binders, called “AdPROM.” Here, we used CRISPR/Cas9 technology to knock in a GFP tag on the native K-RAS gene in A549 adenocarcinoma (A549^GFPKRAS) cells and constructed AdPROMs containing high-affinity GFP or H/K-RAS binders. Expression of GFP-targeting AdPROM in A549^GFPKRAS led to robust proteasomal degradation of endogenous GFP-K-RAS, while expression of anti-HRAS-targeting AdPROM in different cell lines resulted in the degradation of both GFP-tagged and untagged K-RAS, and untagged H-RAS. Our findings imply that endogenous RAS proteins can be targeted for proteolysis, supporting the idea of an alternative therapeutic approach to these undruggable targets.

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Generation of A549 cells with a homozygous knockin of GFP tag on the KRAS gene

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Proteasomal degradation of endogenous GFP-K-RAS using a VHL-GFP-nanobody fusion

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Proteasomal degradation of endogenous H/K-RAS using VHL-H/K-RAS-monobody fusion

KRAS-associated microRNAs in colorectal cancer

Colorectal cancer (CRC) is one of the leading causes of cancerrelated death worldwide. Despite progress in treatment of cancers, CRC with KRAS mutations are resistant towards anti-EGFR treatment. MicroRNAs have been discovered in an exponential manner within the last few years and have been known to exert either an onco-miRNA or tumor suppressive effect. Here, the various roles of microRNAs involved in the initiation and progression of KRAS-regulated CRC are summarized. A thorough understanding of the roles and functions of the plethora of microRNAs associated with KRAS in CRC will grant insights into the provision of other potential therapeutic targets as well as treatment. MicroRNAs may also serve as potential molecular classifier or early detection biomarkers for future treatment and diagnosis of CRC.

microRNA-181 serves as a dual-role regulator in the development of human cancers

MicroRNAs (miRNAs) as the regulatory short noncoding RNAs are involved in a wide array of cellular and molecular processes. They negatively regulate gene expression and their dysfunction is correlated with cancer development through modulation of multiple signaling pathways. Therefore, these molecules could be considered as novel biomarkers and therapeutic targets for more effective management of human cancers. Recent studies have demonstrated that the miR-181 family is dysregulated in various tumor tissues and plays a pivotal role in carcinogenesis. They have been shown to act as oncomirs or tumor suppressors considering their mRNA targets and to be involved in cell proliferation, apoptosis, autophagy, angiogenesis and drug resistance. Additionally, these miRNAs have been demonstrated to exert their regulatory effects through modulating multiple signaling pathways including PI3K/AKT, MAPK, TGF-b, Wnt, NF-κB, Notch pathways. Given that, in this review, we briefly summarise the recent studies that have focused on the roles of miRNA-181 family as the multifunctional miRNAs in tumorigenesis and cancer development. These miRNAs may serve as diagnostic and prognostic biomarkers or therapeutic targets in human cancer gene therapy.

Non-Coding RNAs in Lung Tumor Initiation and Progression

Lung cancer is one of the deadliest forms of cancer affecting society today. Non-coding RNAs, such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), through the transcriptional, post-transcriptional, and epigenetic changes they impose, have been found to be dysregulated to affect lung cancer tumorigenesis and metastasis. This review will briefly summarize hallmarks involved in lung cancer initiation and progression. For initiation, these hallmarks include tumor initiating cells, immortalization, activation of oncogenes and inactivation of tumor suppressors. Hallmarks involved in lung cancer progression include metastasis and drug tolerance and resistance. The targeting of these hallmarks with non-coding RNAs can affect vital metabolic and cell signaling pathways, which as a result can potentially have a role in cancerous and pathological processes. By further understanding non-coding RNAs, researchers can work towards diagnoses and treatments to improve early detection and clinical response.

An Emerging Class of Long Non-coding RNA With Oncogenic Role Arises From the snoRNA Host Genes

The small nucleolar RNA host genes (SNHGs) are a group of long non-coding RNAs, which are reported in many studies as being overexpressed in various cancers. With very few exceptions, the SNHGs (SNHG1, SNHG3, SNHG5, SNHG6, SNHG7, SNHG12, SNHG15, SNHG16, SNHG20) are recognized as inducing increased proliferation, cell cycle progression, invasion, and metastasis of cancer cells, which makes this class of transcripts a viable biomarker for cancer development and aggressiveness. Through our literature research, we also found that silencing of SNHGs through small interfering RNAs or short hairpin RNAs is very effective in both in vitro and in vivo experiments by lowering the aggressiveness of solid cancers. The knockdown of SNHG as a new cancer therapeutic option should be investigated more in the future.

The regulation and interaction of PVT1 and miR181a-5p contributes to the repression of SP1 expression by the combination of XJD decoction and cisplatin in human lung cancer cells

The Chinese herbal prescription Xiaoji decoction (XJD) has been used as an adjuvant treatment of cancer for decades. However, the molecular mechanisms underlying XJD enhancement of the efficiency of chemotherapy were undetermined. In this study, we observed that combination of XJD and cisplatin (DDP) showed a greater inhibition on growth and induced a high magnitude of apoptosis in non-small cell lung cancer (NSCLC) cells. We also found that XJD decreased lncRNA PVT1 and increased miR181a-5p expressions. There was a reciprocal interaction between PVT1 and miR181a-5p. XJD decreased SP1 protein, which were overcame by overexpressed PVT1 and inhibitors of miR181a-5p. Overexpressed SP1 reversed the inhibitory effect of XJD on cell growth. Importantly, XJD and DDP exhibited synergy on regulation of PVT1, miR181a-5p, and SP1 expressions. The similar results were observed in one in vivo model. In conclusions, XJD inhibits NSCLC cell growth via reciprocal interaction of PVT1 and miR181a-5p followed by reducing SP1 expression. XJD and DDP exhibit synergy. This study provides a novel mechanism by which XJD enhances the anti-cancer effect of DDP in NSCLC cells.

miR-181a/b-5p regulates human umbilical vein endothelial cell angiogenesis by targeting PDGFRA

Type 2 diabetes mellitus (T2DM) is a growing burden in low-and middle-income countries. Changing lifestyles and lack of physical activity are some of the reasons contributing to this epidemic increase. Co-morbidities associated with T2DM are largely due to the complications which arise as a consequence of endothelial dysfunction. Platelet derived growth factor-alpha (PDGFRA) is a protein responsible for cell proliferation, angiogenesis, migration and invasion. Increased levels of PDGFRA have been reported in T2DM. This study assessed the epigenetic regulation of PDGFRA through microRNAs (miR-181a/b-5p).Using a bioinformatics-based approach, we assessed the binding of miR-181a/b-5p to PDGFRA. Experimentally, this binding was confirmed using a dual luciferase reporter assay. Further, we overexpressed miR-181a/b-5p in Human umbilical vein endothelial cells (HUVECs) and the influence of over-expression on cell proliferation, migration and angiogenesis was assessed using in-vitro approaches. The influence of miR-181a/b-5p over expression on cellular apoptosis was ascertained using a TUNEL assay with concomitant changes being observed in the levels of Bcl-2 and cleaved Caspase-3.In HUVECs, PDGFRA is a direct target for miR-181a/b-5p. Over expression of miR-181a/b-5p decreased cellular proliferation, migration, invasion, and tube formation-a surrogate marker for angiogenesis. miR-181a/b-5p may be used as a therapeutic intervention to restrict uncontrolled levels of PDGFRA and thereby rescue the phenotypes of increased cell proliferation, migration, invasion and tube formation. miR-181a/b negatively regulates PDGFRA levels. Significance of the study: T2DM and its associated complications emerge from endothelial dysfunction. The associated phenotypes are regulated by a number of proteins, one such member being, PDGFRA. PDGFRA is in turn regulated by miR-181a/b-5p. Complementation with miR-181a/b-5p resulted in reversion of phenotypes. Thus, miR-181a/b-5p-mediated suppression of PDGFRA may be used as a therapeutic intervention in the management of type 2 diabetes.

Noncoding RNAs and Liquid Biopsy in Lung Cancer: A Literature Review

Lung cancer represents a genetically heterogeneous disease with low survival rates. Recent data have evidenced key roles of noncoding RNAs in lung cancer initiation and progression. These functional RNA molecules that can act as both oncogenes and tumor suppressors may become future biomarkers and more efficient therapeutic targets. In the precision medicine era, circulating nucleic acids have the potential to reshape the management and prognosis of cancer patients. Detecting genomic alterations and level variations of circulating nucleic acids in liquid biopsy samples represents a noninvasive method for portraying tumor burden. Research is currently trying to validate the potential role of liquid biopsy in lung cancer screening, prognosis, monitoring of disease progression, and treatment response. However, this method requires complex detection assays, and implementation of plasma genotyping in clinical practice continues to be hindered by discrepancies that arise when compared to tissue genotyping. Understanding the genomic landscape of lung cancer is essential in order to provide useful and innovative research in the age of patient-tailored therapy. In this landscape, the noncoding RNAs play a crucial role due to their target genes that dramatically influence the tumor microenvironment and the response to therapy. This article addresses present and future possible roles of liquid biopsy in lung cancer. It also discusses how the complex role of noncoding RNAs in lung tumorigenesis could influence the management of this pathology.

MicroRNAs in non-small cell lung cancer: Gene regulation, impact on cancer cellular processes, and therapeutic potential

Lung cancer remains the most lethal cancer among men and women in the United States and worldwide. The majority of lung cancer cases are classified as non-small cell lung cancer (NSCLC). Developing new therapeutics on the basis of better understanding of NSCLC biology is critical to improve the treatment of NSCLC. MicroRNAs (miRNAs or miRs) are a superfamily of genome-derived, small noncoding RNAs that govern posttranscriptional gene expression in cells. Functional miRNAs are commonly dysregulated in NSCLC, caused by genomic deletion, methylation, or altered processing, which may lead to the changes of many cancer-related pathways and processes, such as growth and death signaling, metabolism, angiogenesis, cell cycle, and epithelial to mesenchymal transition, as well as sensitivity to current therapies. With the understanding of miRNA biology in NSCLC, there are growing interests in developing new therapeutic strategies, namely restoration of tumor suppressive miRNAs and inhibition of tumor promotive miRNAs, to combat against NSCLC. In this article, we provide an overview on the molecular features of NSCLC and current treatment options with a focus on pharmacotherapy and personalized medicine. By illustrating the roles of miRNAs in the control of NSCLC tumorigenesis and progression, we highlight the latest efforts in assessing miRNA-based therapies in animal models and discuss some critical challenges in developing RNA therapeutics.

MicroRNA-181a-5p Regulates Inflammatory Response of Macrophages in Sepsis

The aim of this study was to evaluate the role of miR-181a-5p in sepsis, and to further explore the molecular mechanism. RAW 264.7 cells were stimulated with 1 μg/ml LPS for 4 hours. Firstly, qRT-PCR and ELISA was adopted to evaluate the expression of miR-181a-5p and p ro-inflammatory cytokines in RAW 264.7 macrophages a fter LPS stimulation. Results showed that pro-inflammatory cytokines and miR-181a-5p were significantly increased after LPS treatment. Then, we identified that sirtuin-1 (SIRT1) was a direct target of miR-181a-5p and it was down-regulated in LPS treated RAW264.7 macrophages. Furthermore, the data suggested that the miR-181a-5p inhibitor significantly inhibited LPS enhanced inflammatory cytokines expression and NF-κB pathway activation, and these changes were eliminated by SIRT1 silencing. Moreover, the role of the miR-181a-5p inhibitor on sepsis was studied in vivo. We found that the miR-181a-5p inhibitor significantly decreased the secretion of inflammatory factors, and the levels of creatine (Cr), blood urea nitrogen (BUN), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in a serum for mice with sepsis. However, all the effects were reversed by SIRT1-siRNA. In summary, these results indicated that miR-181a-5p was involved in sepsis through regulating the inflammatory response by targeting SIRT1, suggesting that miR-181a-5p may be a potential target for the treatment of sepsis.

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

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

MicroRNA Changes in Firefighters

Objectives:

Firefighters have elevated cancer incidence and mortality rates. MicroRNAs play prominent roles in carcinogenesis, but have not been previously evaluated in firefighters.

Methods:

Blood from 52 incumbent and 45 new recruit nonsmoking firefighters was analyzed for microRNA expression, and the results adjusted for age, obesity, ethnicity, and multiple comparisons.

Results:

Nine microRNAs were identified with at least a 1.5-fold significant difference between groups. All six microRNAs with decreased expression in incumbent firefighters have been reported to have tumor suppressor activity or are associated with cancer survival, and two of the three microRNAs with increased expression in incumbent firefighters have activities consistent with cancer promotion, with the remaining microRNA associated with neurological disease.

Conclusion:

Incumbent firefighters showed differential microRNA expression compared with new recruits, providing potential mechanisms for increased cancer risk in firefighters.

SNHG12: An LncRNA as a Potential Therapeutic Target and Biomarker for Human Cancer

Limitations in current diagnostic procedures warrant identification of new methodologies to improve diagnoses of cancer patients. In this context, long non-coding RNAs (lncRNAs) have emerged as stable biomarkers which are expressed abundantly in tumors. Importantly, these can be detected at all stages of tumor development, and thus may provide potential biomarkers and/or therapeutic targets. Recently, we suggested that aberrant levels of lncRNAs can be used to determine the invasive and metastatic potential of tumor cells. Further, direct correlations of lncRNAs with cancer-derived inflammation, metastasis, epithelial-to-mesenchymal transition, and other hallmarks of cancer indicate their potential as biomarkers and targets for cancer. Thus, in this review we have discussed the importance of small nucleolar RNA host gene 12 (SNHG12), a lncRNA, as a potential biomarker for a variety of cancers. A meta-analysis of a large cohort of cancer patients revealed that SNHG12 may also serve as a potential target for cancer-directed interventions due to its involvement in unfolded protein responses, which many tumor cells exploit to both evade immune-mediated attack and enhance the polarization of effector immune cells (e.g., macrophages and T cells). Thus, we propose that SNHG12 may serve as both a biomarker and a druggable therapeutic target with promising clinical potential.

An Isoxazole Derivative SHU00238 Suppresses Colorectal Cancer Growth through miRNAs Regulation

Colorectal cancer (CRC) is a leading cause of cancer-related deaths worldwide. Isoxazoline and isoxazole derivatives represent an important class of five-membered heterocycles, which play a pivotal role in drug discovery. In our previous study, we developed a series of isoxazole derivatives with an efficient method. In this study, we evaluated their effects on tumor cell growth. HCT116 cells were treated with isoxazole derivatives; an cholecystokinin octapeptide (CCK-8) assay was used to calculate the IC₅₀ (half maximal inhibitory concentration) of each derivative. Compound SHU00238, which was obtained by the copper nitrate-mediated [2+2+1] cycloaddition reaction of olefinic azlactone with naphthalene-1,4-dione, has a lower IC₅₀; we analyzed its inhibitory activity in further assays. Cell apoptosis was estimated by flow cytometry analysis in vitro. SHU00238 injection was used to treat tumor-bearing mice. We found that SHU00238 suppressed cell viability and promoted cell apoptosis in vitro. SHU00238 treatment significantly inhibited colonic tumor growth in vivo. Furthermore, we compared the miRNAs expression changes in HCT116 cells before and after SHU00238 treatment. MiRNA profiling revealed that SHU00238 treatment affected cell fate by regulating a set of miRNAs. In conclusion, SHU00238 impedes CRC tumor cell proliferation and promotes cell apoptosis by miRNAs regulation.

Interference of the long noncoding RNA CDKN2B-AS1 upregulates miR-181a-5p/TGFβI axis to restrain the metastasis and promote apoptosis and senescence of cervical cancer cells

Long noncoding RNA (lncRNA) CDKN2B-AS1 has been shown to play a crucial role in the development as well as in the prognosis of various human cancers, including cervical cancer. However, the underlying mechanisms need to be further explored between CDKN2B-AS1 and cervical cancer. In the present study, RT-PCR showed that the mRNA level of CDKN2B-AS1 was significantly upregulated while the miR-181a-5p was downregulated in cervical cancer cell lines. In addition, the interference of CDKN2B-AS1 by shRNA resulted in the suppression of cell proliferation, invasion, migration and promotion of apoptosis and senescence, and either CDKN2B-AS1 overexpression or miR-181a-5p showed reversed results. Further studies demonstrated that CDKN2B-AS1 could directly interact with miR-181a-5p, and that there was an inverse correlation between miR-181a-5p and CDKN2B-AS1. In addition, we found that TGFβI was a target of miR-181a-5p and could be downregulated by CDKN2B-AS1 knockdown. Moreover, the in vivo experiments further demonstrated the contribution of CDKN2B-AS1 in cervical cancer including tumor growth, apoptosis inhibition and senescence inhibition, and CDKN2B-AS1 knockdown could inhibit the aforementioned activities. In summary, our study demonstrated that the CDKN2B-AS1/miR-181a-5p/TGFβI axis might play a vital role in cervical cancer development.

The Roles of MicroRNA in Lung Cancer

Lung cancer is the most devastating malignancy in the world. Beyond genetic research, epigenomic studies—especially investigations of microRNAs—have grown rapidly in quantity and quality in the past decade. This has enriched our understanding about basic cancer biology and lit up the opportunities for potential therapeutic development. In this review, we summarize the involvement of microRNAs in lung cancer carcinogenesis and behavior, by illustrating the relationship to each cancer hallmark capability, and in addition, we briefly describe the clinical applications of microRNAs in lung cancer diagnosis and prognosis. Finally, we discuss the potential therapeutic use of microRNAs in lung cancer.

Tumor-suppressive effects of microRNA-181d-5p on non-small-cell lung cancer through the CDKN3-mediated Akt signaling pathway in vivo and in vitro

The involvement of several microRNAs (miRs) in the initiation and development of tumors through the suppression of the target gene expression has been highlighted. The aberrant expression of miR-181d-5p and cyclin-dependent kinase inhibitor 3 (CDKN3) in non-small-cell lung cancer (NSCLC) was then screened by microarray analysis. In the present study, we performed a series of in vivo and in vitro experiments for the purpose of investigating their roles in NSCLC and the underlying mechanism. There was a high expression of CDKN3, whereas miR-181d-5p was downregulated in NSCLC. Quantitative RT-PCR, Western blot analysis, and dual-luciferase reporter gene assay further identified that CDKN3 could be negatively regulated by miR-181d-5p. Moreover, the upregulation of miR-181d-5p or silencing of CDKN3 could inactivate the Akt signaling pathway. A549 with the lowest miR-181d-5p and H1975 with the highest CDKN3 among the five NSCLC cell lines (H1299, A549, H1975, NCI-H157, and GLC-82) were adopted for in vitro experiments, in which expression of miR-181d-5p and CDKN3 was altered by transfection of miR-181d-5p mimic/inhibitor or siRNA-targeting CDKN3. Afterwards, cell proliferation, apoptosis, invasion, migration, and angiogenesis, as well as epithelial-mesenchymal transition (EMT), were evaluated, and tumorigenicity was assessed. In addition, an elevation in miR-181d-5p or depletion in CDKN3 led to significant reductions in proliferation, invasion, migration, angiogenesis, EMT, and tumorigenicity of NSCLC cells, coupling with increased cell apoptosis. In conclusion, this study highlights the tumor-suppressive effects of miR-181d-5p on NSCLC via Akt signaling pathway inactivation by suppressing CDKN3, thus providing a promising therapeutic strategy for the treatment of NSCLC.

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

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

Retracted Article: CircRNA PVT1 modulates cell metastasis via the miR-181a-5p/NEK7 axis and cisplatin chemoresistance through miR-181a-5p-mediated autophagy in non-small cell lung cancer

In the initiation and evolution of human cancers, circular RNAs (circRNAs) act as crucial regulators. The aim of this report was to ascertain the functional mechanisms of circRNA plasmacytoma variant translocation 1 (circPVT1) in the metastasis and chemoresistance of non-small cell lung cancer (NSCLC). The levels of circPVT1, microRNA-181a-5p (miR-181a-5p) and non-inherited maternal antigens-related kinase 7 (NEK7) were examined via quantitative real-time polymerase chain reaction (qRT-PCR). The levels of the associated proteins were determined through western blot. Cell counting kit-8 (CCK-8) and flow cytometry were used to assess the half inhibitory concentration (IC₅₀) of cisplatin and cell apoptosis, respectively. Cell invasion was detected by transwell assay. A dual-luciferase reporter assay and RNA immunoprecipitation (RIP) were used to confirm the target relation. The impact of circPVT1 on cisplatin chemoresistance in vivo was investigated using xenograft experiments. CircPVT1 and NEK7 were up-regulated and miR-181a-5p was down-regulated in NSCLC. CircPVT1 knockdown refrained the cisplatin chemoresistance and metastasis of NSCLC cells. MiR-181a-5p was a target of circPVT1 and circPVT1 inhibition alleviated the effects of a miR-181a-5p inhibitor on NSCLC cells. The decrease of circPVT1 accentuated the si-NEK7-inhibited metastasis by the miR-181a-5p/NEK7 axis and relieved the 3-methyladenine (3-MA)-promoted cisplatin chemoresistance by miR-181a-5p-mediated autophagy. Down-regulation of circPVT1 facilitated the cisplatin sensitivity of NSCLC cells in vivo. Due to the modulation of cell metastasis via the miR-181a-5p/NEK7 axis and cisplatin chemoresistance by miR-181a-5p-mediated autophagy in NSCLC, circPVT1 might act as an appreciable therapeutic marker for NSCLC.

In the initiation and evolution of human cancers, circular RNAs (circRNAs) act as crucial regulators.

MicroRNA-296, a suppressor non-coding RNA, downregulates SGLT2 expression in lung cancer

Non-small cell lung cancer (NSCLC) is one of the most common types of cancer worldwide and has the highest mortality rate in China. MicroRNAs (miRNAs or miRs) are involved in tumorigenesis and their important role in cancer is becoming increasingly apparent. The expression of miR‑296‑5p in particular has been shown to be significantly downregulated in lung cancer. Sodium-glucose co-transporter-2 [SGLT2, also known as solute carrier family 5 member 2 (SLC5A2)] is an oncogene that promotes tumorigenesis. In this study, we aimed to determine the role of miR‑296‑5p in lung cancer and whether this involves the targeting of SGLT2. For this purpose, we examined miR‑296‑5p and SGLT2 expression in human lung cancer samples and cell lines by RT-qPCR and western blot analysis. In addition, the data analysis website TCGA was used for survival analysis with respect to SGLT2 expression. The effects of miR‑296‑5p were also examined on cell proliferation and cell cycle progression using respective assays. The results demonstrate that miR‑296‑5p is significantly downregulated in NSCLC tissues. Additionally, it is demonstrated that SGLT2 is directly targeted by miR‑296‑5p. Furthermore, our data reveal that the knockdown of SGLT2 using siRNA inhibits cell proliferation and impedes cell cycle progression. Collectively, data suggest that miR‑296‑5p not only inhibits NSCLC by downregulating SGLT2 expression, but also acts as a novel regulator of aberrant lung cancer cells to limit lung cancer progression.

miRNAs deregulation in lung cells exposed to airborne particulate matter (PM10) is associated with pathways deregulated in lung tumors

Particulate matter (PM) is an environmental pollutant that has been associated with an increased risk for lung cancer. PM exposure induces cellular alterations and the deregulation of cell signaling pathways. However other mechanisms such as microRNAs deregulation, might be involved in the development and progression of some types of epithelial cancer. The aim of this work was to evaluate miRNA expression in epithelial lung cells after exposure to PM₁₀ and to identify the possible gene targets of deregulated miRNAs. We measured the expression of 2538 miRNAs using a microarray platform after 72 h of PM₁₀ exposure; the potential biological function was inferred with bioinformatics analysis and we validated the relative expression of 10 selected miRNAs with real-time PCR. We found that the expression of 74 miRNAs was significantly changed: 45 miRNAs were downregulated and were involved in proliferation, cell cycle, cytoskeleton modification and autophagy; meanwhile, 29 miRNAs related to apoptosis, DNA damage repair and xenobiotic metabolism were upregulated.

MiR-181a/b induce the growth, invasion, and metastasis of neuroblastoma cells through targeting ABI1

Neuroblastoma is a pediatric malignancy, and the clinical phenotypes range from localized tumors with excellent outcomes to widely metastatic disease in which long-term survival is approximately 40%, despite intensive therapy. Emerging evidence suggests that aberrant miRNA regulation plays a role in neuroblastoma, but the miRNA functions and mechanisms remain unknown. miR-181 family members were detected in 32 neuroblastoma patients, and the effects of miR-181a/b on cell viability, invasion, and migration were evaluated in vitro and in vivo. A parallel global mRNA expression profile was obtained for neuroblastoma cells overexpressing miR-181a. The potential targets of miR-181a/b were validated. miR-181a/b expression levels were positively associated with MYCN amplification and neuroblastoma aggressiveness. Moreover, ectopic miR-181a/b expression significantly induced the growth and invasion of neuroblastoma cells in vitro and in vivo. Microarray analysis revealed that mRNAs were consistently downregulated after miR-181a overexpression, leading to cell migration. In addition, the expression of ABI1 was suppressed by miR-181a/b, and ABI1 was validated as a direct target of miR-181a/b. We concluded that miR-181a/b were significantly upregulated in aggressive neuroblastoma, which enhanced its tumorigenesis and progression by suppressing the expression of ABI1.

The Role of MicroRNA-181a in Myocardial Fibrosis Following Myocardial Infarction in a Rat Model

Background

The role of miR-181a in the development of cardiac disease and in particular, myocardial fibrosis following myocardial infarction (MI) remains unknown. The aim of this study was to explore the role of miR-181a in myocardial fibrosis in a rat model of MI and the expression of TGF-β receptor III (TβRIII).

Material/Methods

Forty adult male Wistar rats were randomly divided into an MI model group (n=30) and a control group with (n=10). The rat MI model involved ligating the left anterior descending (LAD) coronary artery in the model group; the control group was treated with a sham operation. Cardiac function was assessed using cardiac ultrasound. Myocardial fibroblasts were extracted from the rat hearts and transfected with a miR-mimic or miR-inhibitor, and cell growth was measured using an MTT assay. The level of miR-181a expression was detected using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blots.

Results

miR-181a expression was significantly increased during the progression of MI (P<0.05). Over-expression of miR-181a was associated with increased deposition of extracellular matrix (ECM) components, collagen I and fibronectin. This effect was reversed with the use of a miR-181a inhibitor (P<0.05). Upregulation of miR-181a suppressed the expression of TGF-β receptor III (TβRIII) by binding with 3′-UTR.

Conclusions

In this rat model of MI, the findings were that miR-181a had a role in the progression of myocardial fibrosis. The findings require further studies to determine whether miR-181a might provide a novel therapeutic target to limit myocardial fibrosis following MI.

Identification of four plasma microRNAs as potential biomarkers in the diagnosis of male lung squamous cell carcinoma patients in China

Dysregulated microRNAs (miRNAs) in the plasma of patients with lung squamous cell carcinoma (LSCC) might serve as biomarkers for LSCC diagnosis. The expression of miRNAs was performed using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) on the basis of Exiqon panels in the initial screening phase including three male LSCC pool samples and one normal control (NC) pool sample (per 10 samples were pooled as one pool sample). After the training (32 LSCC vs. 31 NCs), the testing (55 LSCC vs. 55 NCs), and the external validation (15 LSCC vs. 15 NCs) stages via qRT-PCR, a four-miRNA signature (miR-181a-5p, miR-21-5p, miR-106a-5p, and miR-93-5p) was identified for LSCC detection. Areas under the receiver operating characteristic (ROC) curve (AUC) of the four-miRNA panel for the training, the testing, and the external validation phases were 0.795, 0.827, and 0.914, respectively. Then, the four miRNAs were explored in LSCC tissue samples (23 LSCC vs. 23 NCs), and their expression was significantly up-regulated. However, none of the four miRNAs found significantly up-regulated in plasma exosomes expect miR-93-5p with borderline significance (16 LSCC vs. 16 NCs). In summary, our study established a four-miRNA peripheral plasma signature, which contributed to diagnosing male LSCC patients in China to a certain degree.

microRNA‑181a‑5p functions as an oncogene in renal cell carcinoma

Renal cell carcinoma (RCC) is one of the most common urinary tumors. Previous studies have demonstrated that microRNA (miR)‑181a‑5p has an important role in numerous types of cancer. However, the function of miR‑181a‑5p in RCC remains unknown. In the present study, the expression levels of miR‑181a‑5p in RCC tissues and cell lines were investigated using reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) analysis. The results of the RT‑qPCR analyses suggested that the expression of miR‑181a‑5p was upregulated in RCC tissues and cells lines compared with adjacent normal renal tissues and normal renal cell lines. Furthermore, the effect of miR‑181a‑5p on cell proliferation, migration, invasion and apoptosis was investigated in the present study. Overexpression of miR‑181a‑5p was revealed to suppress the apoptosis of 786‑O and ACHN cells, in addition to enhancing the proliferation, migration and invasion abilities of 786‑O and ACHN cells in vitro, thus suggesting that miR‑181a‑5p may function as an oncogene in RCC. However, further studies are required to investigate the underlying mechanism of miR‑181a‑5p and its potential role as a biomarker for early detection and prognosis, in addition to as a therapeutic target in RCC.

Epidermal growth factor receptor (EGFR): A rising star in the era of precision medicine of lung cancer

Lung cancer is a leading cause of cancer mortality worldwide. In tumors, the important role of noncoding RNA regulatory networks has been more and more reveal. EGFR has been identified as an oncogenic driver of NSCLC, especially activating mutations EGFR and its inhibition with specific TKIs can generate dramatic tumor responses. Studies have shown that EGFR plays significant roles in the progression of NSCLC. Subset analysis of the small proportion of patients with EGFR-mutant lung cancer showed a disease-free survival benefit, but was underpowered to detect a survival advantage. Herein, we highlight the progression of EGFR, noncoding RNA, and their roles in carcinogenesis. We also focus on anti-lung cancer drug development and EGFR-related drug resistance.

Blood and lung microRNAs as biomarkers of pulmonary tumorigenesis in cigarette smoke-exposed mice

Cigarette smoke (CS) is known to dysregulate microRNA expression profiles in the lungs of mice, rats, and humans, thereby modulating several pathways involved in lung carcinogenesis and other CS-related diseases. We designed a study aimed at evaluating (a) the expression of 1135 microRNAs in the lung of Swiss H mice exposed to mainstream CS during the first 4 months of life and thereafter kept in filtered air for an additional 3.5 months, (b) the relationship between lung microRNA profiles and histopathological alterations in the lung, (c) intergender differences in microRNA expression, and (d) the comparison with microRNA profiles in blood serum. CS caused multiple histopathological alterations in the lung, which were almost absent in sham-exposed mice. An extensive microRNA dysregulation was detected in the lung of CS-exposed mice. Modulation of microRNA profiles was specifically related to the histopathological picture, no effect being detected in lung fragments with non-neoplastic lung diseases (emphysema or alveolar epithelial hyperplasia), whereas a close association occurred with the presence and multiplicity of preneoplastic lesions (microadenomas) and benign lung tumors (adenomas). Three microRNAs regulating estrogen and HER2-dependent mechanisms were modulated in the lung of adenoma-bearing female mice. Blood microRNAs were also modulated in mice affected by early neoplastic lesions. However, there was a poor association between lung microRNAs and circulating microRNAs, which can be ascribed to an impaired release of mature microRNAs from the damaged lung. Studies in progress are evaluating the feasibility of analyzing blood microRNAs as a molecular tool for lung cancer secondary prevention.

Long non-coding RNA CCAT1 promotes multiple myeloma progression by acting as a molecular sponge of miR-181a-5p to modulate HOXA1 expression

Multiple myeloma (MM) is the second most common hematological cancer all over the world. Long non-coding RNA (lncRNA) colon cancer associated transcript-1 (CCAT1) has been reported to play important roles in the development and progression of multiple human malignancies. However, little is known about its functional role and molecular mechanism in MM. The aim of this study was to investigate the clinical and biological significance of CCAT1 in MM. Our data showed that the relative expression levels of CCAT1 were significantly upregulated in MM tissues and cell lines compared with healthy donors and normal plasma cells (nPCs). High expression of CCAT1 was correlated shorter overall survival of MM patients. CCAT1 knockdown significantly inhibited cell proliferation, induced cell cycle arrest at G0/G1 phase and promoted cell apoptosis in vitro, and suppressed tumor growth in vivo. MiR-181a-5p was a direct target of CCAT1, and repression of miR-181a-5p could rescue the inhibition of CCAT1 knockdown on MM progression. In addition, CCAT1 positively regulated HOXA1 expression through sponging miR-181a-5p in MM cells.taken together, lncRNA CCAT1 exerted an oncogenic role in MM by acting as a ceRNA of miR-181a-5p. These results suggest that CCAT1 may serve as a novel diagnostic marker and therapeutic target for MM.