miR-608 regulates apoptosis in human lung adenocarcinoma via regulation of AKT2

Screening and analysis of single nucleotide polymorphism in the 3'-UTR microRNA target regions and its implications for lung tumorigenesis

Aim: The study aims to identify high-impact single nucleotide polymorphisms (SNPs) in miRNA target sites of genes associated with lung cancer.Materials & methods: Lung cancer genes were obtained from Uniprot KB. miRNA target site SNPs were mined from MirSNP, miRdSNP and TargetScan. SNPs were shortlisted based on binding impact, minor allele frequency and conservation. Gene expression was analyzed in genes with high-impact SNPs in healthy versus lung cancer tissue. Additionally, enrichment, pathway and network analyzes were performed.Results: 19 high-impact SNPs were identified in miRNA target sites of lung cancer-associated genes. These SNPs affect miRNA binding and gene expression. The genes are involved in key cancer related pathways.Conclusion: The identified high-impact miRNA target site SNPs and associated genes provide a starting point for case-control studies in lung cancer patients in different populations.

Regulation and therapeutic potentials of microRNAs to non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, accounting for 80%-85% of total cases and leading to millions of deaths worldwide. Drug resistance is the primary cause of treatment failure in NSCLC, which urges scientists to develop advanced approaches for NSCLC treatment. Among novel approaches, the miRNA-based method has emerged as a potential approach as it allows researchers to modulate target gene expression. Subsequently, cell behaviors are altered, which leads to the death and the depletion of cancer cells. It has been reported that miRNAs possess the capacity to regulate multiple genes that are involved in various signaling pathways, including the phosphoinositide 3-kinase, receptor tyrosine kinase/rat sarcoma virus/mitogen-activated protein kinase, wingless/integrated, retinoblastoma, p53, transforming growth factor β, and nuclear factor-kappa B pathways. Dysregulation of these signaling pathways in NSCLC results in abnormal cell proliferation, tissue invasion, and drug resistance while inhibiting apoptosis. Thus, understanding the roles of miRNAs in regulating these signaling pathways may enable the development of novel NSCLC treatment therapies. However, a comprehensive review of potential miRNAs in NSCLC treatment has been lacking. Therefore, this review aims to fill the gap by summarizing the up-to-date information on miRNAs regarding their targets, impact on cancer-associated pathways, and prospective outcomes in treating NSCLC. We also discuss current technologies for delivering miRNAs to the target cells, including virus-based, non-viral, and emerging extracellular vesicle-based delivery systems. This knowledge will support future studies to develop an innovative miRNA-based therapy and select a suitable carrier to treat NSCLC effectively.

Zebrafish in Lung Cancer Research

Zebrafish is increasingly used as a model organism for cancer research because of its genetic and physiological similarities to humans. Modeling lung cancer (LC) in zebrafish has received significant attention. This review focuses on the insights gained from using zebrafish in LC research. These insights range from investigating the genetic and molecular mechanisms that contribute to the development and progression of LC to identifying potential drug targets, testing the efficacy and toxicity of new therapies, and applying zebrafish for personalized medicine studies. This review provides a comprehensive overview of the current state of LC research performed using zebrafish, highlights the advantages and limitations of this model organism, and discusses future directions in the field.

Functional Screen for microRNAs Suppressing Anchorage-Independent Growth in Human Cervical Cancer Cells

The progression of anchorage-dependent epithelial cells to anchorage-independent growth represents a critical hallmark of malignant transformation. Using an in vitro model of human papillomavirus (HPV)-induced transformation, we previously showed that acquisition of anchorage-independent growth is associated with marked (epi)genetic changes, including altered expression of microRNAs. However, the laborious nature of the conventional growth method in soft agar to measure this phenotype hampers a high-throughput analysis. We developed alternative functional screening methods using 96- and 384-well ultra-low attachment plates to systematically investigate microRNAs regulating anchorage-independent growth. SiHa cervical cancer cells were transfected with a microRNA mimic library (n = 2019) and evaluated for cell viability. We identified 84 microRNAs that consistently suppressed growth in three independent experiments. Further validation in three cell lines and comparison of growth in adherent and ultra-low attachment plates yielded 40 microRNAs that specifically reduced anchorage-independent growth. In conclusion, ultra-low attachment plates are a promising alternative for soft-agar assays to study anchorage-independent growth and are suitable for high-throughput functional screening. Anchorage independence suppressing microRNAs identified through our screen were successfully validated in three cell lines. These microRNAs may provide specific biomarkers for detecting and treating HPV-induced precancerous lesions progressing to invasive cancer, the most critical stage during cervical cancer development.

Biological Functions and Molecular Mechanisms of MiR-608 in Cancer

In recent years, microRNAs (miRNAs) have attracted much attention because of their prominent role in cancer. An increasing number of studies have shown that miRNAs play an important role in a variety of tumors. miR-608 has been reported to be decreased in cancers, especially in solid tumors. miR-608 is regarded as a tumor suppressor, which has been verified through a large number of experiments both in vivo and in vitro. miR-608 participates in many biological processes, including cell proliferation, invasion, migration, and apoptosis, by inhibiting transmembrane proteins and many signaling pathways. Here, we summarize the expression profile and biological functions and mechanism of miR-608, suggesting that miR-608 is an ideal diagnostic and prognostic biomarker and a treatment target for cancer.

Knockdown of long non-coding MIR210HG inhibits cell proliferation, migration, and invasion in hepatoblastoma via the microRNA-608-FOXO6 axis

Objective

Hepatoblastoma is the most common liver tumor. Recent research has found that long non-coding (lnc)RNAs are involved in multiple types of cancers, but the potential mechanism of lncRNA MIR210HG in hepatoblastoma remains unknown. The present study explored the molecular mechanism of MIR210HG in hepatoblastoma progression.

Methods

The cell counting kit-8 was used to detect cell viability, and Transwell assays assessed cell migration and invasion. Luciferase reporter assays showed the relationship between MIR210HG and microRNA (miR)-608 and between miR-608 and forkhead box O6 (FOXO6). Functional tests were verified in vivo by a tumor xenograft model. The expression of MIR210HG, miR-608, FOXO6, E-cadherin, N-cadherin, and vimentin was determined by quantitative reverse transcription polymerase chain reaction and western blotting.

Results

MIR210HG was shown to be highly expressed in hepatoblastoma tissues and cell lines. Knockdown of MIR210HG reduced proliferation, migration, and invasion in liver cancer cells, and suppressed tumor growth in vivo. MIR210HG competitively combined with miR-608, and miR-608 decreased FOXO6 expression.

Conclusion

Our study demonstrated that knockdown of MIR210HG inhibits hepatoblastoma development through binding to miR-608 and downregulating FOXO6. Our results provide novel insights for hepatoblastoma treatment involving the MIR210HG–miR608–FOXO6 axis.

RYR2 mutation in non-small cell lung cancer prolongs survival via down-regulation of DKK1 and up-regulation of GS1-115G20.1: A weighted gene Co-expression network analysis and risk prognostic models

RYR2 mutation is clinically frequent in non-small cell lung cancer (NSCLC) with its function being elusive. We downloaded lung squamous cell carcinoma and lung adenocarcinoma samples from the TCGA database, split the samples into RYR2 mutant group (n = 337) and RYR2 wild group (n = 634), and established Kaplan-Meier curves. The results showed that RYR2 mutant group lived longer than the wild group (p = 0.027). Weighted gene co-expression network analysis (WGCNA) of differentially expressed genes (DEGs) yielded prognosis-related genes. Five mRNAs and 10 lncRNAs were selected to build survival prognostic models with other clinical features. The AUCs of 2 models are 0.622 and 0.565 for predicting survival at 3 years. Among these genes, the AUCs of DKK1 and GS1-115G20.1 expression levels were 0.607 and 0.560, respectively, which predicted the 3-year survival rate of NSCLC sufferers. GSEA identified an association of high DKK1 expression with TP53, MTOR, and VEGF expression. Several target miRNAs interacting with GS1-115G20.1 were observed to show the relationship with the phenotype, treatment, and survival of NSCLC. NSCLC patients with RYR2 mutation may obtain better prognosis by down-regulating DKK1 and up-regulating GS1-115G20.1.

MiR-129-5p/DLX1 signalling axis mediates functions of prostate cancer during malignant progression

We mainly corroborated the potential mechanism of DLX1 and miR-129-5p in prostate cancer cells. DLX1 was upregulated in cancer cells according to qRT-PCR assay. We evaluated the functional changes of the transfected cells via Transwell assay, CCK-8 assay and wound healing assay. DLX1 was confirmed as a cancer promoter. In addition, qRT-PCR showed down-regulated miR-129-5p expression in prostate cancer. We further used dual-luciferase reporter detection to elucidate the targeting between these two genes. The inhibition of miR-129-5p on tumour was verified. Besides, co-transfection of oe-DLX1 and miR-129-5p mimics attenuated this inhibition. These data demonstrated functions of DLX1/miR-129-5p axis in prostate cancer: miR-129-5p hindered the biological functions of cancer cells via inhibiting DLX1 expression. We provide a novel biomarker for prostate cancer.

Vascular endothelial cell-derived exosomal miR-30a-5p inhibits lung adenocarcinoma malignant progression by targeting CCNE2

This study tried to explore the molecular mechanism underlying progression of lung adenocarcinoma (LUAD), and discuss the extracellular communication between cancer cells and vascular endothelial cells. Roughly, differential analysis was carried out to note that miR-30a-5p was lowly expressed in LUAD while CCNE2 was highly expressed. Cell functional experiments demonstrated that overexpressed miR-30a-5p led to suppressed cell abilities in proliferation, migration and invasion. Dual-luciferase reporter gene assay and RNA immunoprecipitation verified the binding of miR-30a-5p and CCNE2, as well as decreased mRNA and protein expression of CCNE2 with miR-30a-5p overexpression. Simultaneous upregulation of miR-30a-5p and CCNE2 reversed the promotion of CCNE2 on malignant behaviors of LUAD cells. In vivo mice experiments exhibited that high miR-30a-5p expression hindered tumor growth. Additionally, miR-30a-5p was localized on the Extracellular Vesicles miRNA (EVmiRNA) database.MiR-30a-5p was abundant in exosomes derived from vascular endothelial cells. To validate that miR-30a-5p could be delivered to LUAD cells via exosomes and then make an effect, exosomes from vascular endothelial cells were firstly extracted and identified by transmission electron microscopy and detection of exosomal marker proteins (Alix, CD63, TSG101). Sequentially, the extracted exosomes were labeled with PKH67 to note that exosomes could be internalized by cancer cells. Further experiments indicated that miR-30a-5p was increased in cancer cells co-cultured with exosomes, which in turn suppressed cell malignant behaviors and made cell cycle arrest. In all, our findings clarified that exosomes derived from vascular endothelial cells delivered miR-30a-5p to LUAD cells to affect tumor malignant progression via the miR-30a-5p/CCNE2 axis.

miR-21-5p promotes lung adenocarcinoma cell proliferation, migration and invasion via targeting WWC2

OBJECTIVE

Studies have suggested that miR-21-5p and WWC2 are key players in most cancer types, yet the underlying mechanisms in lung adenocarcinoma (LUAD) remain elusive. This study made in-depth research on the two factors-dependent mechanisms underlying LUAD occurrence and development.

METHODS

Bioinformatics methods were employed to identify the miRNA and its target gene of interest. In all, 20 pairs of LUAD tumor tissue samples and matched adjacent normal samples along with 5 LUAD cell lines were collected for evaluating the aberrant expression of miR-21-5p and WWC2. Dual-luciferase reporter assay was performed to validate the targeted relationship between miR-21-5p and WWC2. A series of in vitro experiments including colony formation assay, EdU, wound healing assay and Transwell were conducted for assessment of the LUAD cell biological behaviors. In addition, Western blot was carried out to determine the protein expression of epithelial-mesenchymal transition (EMT)-related proteins.

RESULTS

miR-21-5p was found to be considerably increased in LUAD tissue and cells relative to that in the adjacent tissue and the human bronchial epithelial cells, whereas WWC2 was significantly decreased. Dual-luciferase reporter assay revealed that miR-21-5p targeted WWC2 and down-regulated its expression. Besides, silencing miR-21-5p or overexpressing WWC2 played an inhibitory role in PC-9 cancer cell proliferation, migration and invasion, but such effect was suppressed when miR-21-5p was overexpressed. Furthermore, Western blot uncovered that WWC2 overexpression impeded the EMT process in LUAD cells.

CONCLUSION

miR-21-5p facilitates LUAD cell proliferation, migration and invasion through targeting WWC2, which provides a novel therapeutic target for LUAD treatment.

Identification of circ_0089153/miR-608/EGFR p53 axis in ameloblastoma via MAPK signaling pathway

OBJECTIVES

This study investigated the role of circular RNAs (circRNAs) in the pathogenesis of ameloblastoma (AB), identifying potential novel targets for future targeted therapy.

MATERIALS AND METHODS

CircRNA and microRNA (miRNA) profiling in AB were built with microarrays. Six novel circRNAs were validated, circ-miRNA networks were delineated. Hsa-miR-608 was filtered over cross-comparison between database screening, miRNA microarray and validated. Circ-miRNA binding sponge was validated via luciferase reporter assay. Downstream mRNAs were screened. Regulation between miRNAs and mRNAs was confirmed in vitro. Gene interaction networks and circRNA-miRNA-mRNA interaction pathway enrichment analyses were established.

RESULTS

Six differentially expressed circRNAs were selected and validated. According to miRNAs and pathways predicted, six correlated miRNAs were selected, hsa-miR-608 was filtered and validated. The hsa_circ_0089153/hsa-miR-608 binding sponge was validated. Downstream gene interaction networks showed that EGFR and p53 had the strongest co-expression. In vitro transfection results confirmed the suppressive function of miR-608 and EGFR p53. Hsa_circ_0089153/hsa-miR-608/EGFR p53 interaction pathway enrichment analysis confirmed functions mainly enriched in MAPK and related signaling pathways regulating AB progression.

CONCLUSIONS

Six novel circRNAs were identified. Hsa_circ_0089153/hsa-miR-608 sponging was validated, hsa-miR-608 downregulated EGFR and p53, which might further regulate cell proliferation, differentiation, apoptosis, and cell cycle processes via the MAPK signaling pathway.

Expression of MiR-608 in Nonsmall Cell Lung Cancer and Molecular Mechanism of Apoptosis and Migration of A549 Cells

OBJECTIVE

This Work is aimed at exploring the effect of microRNA (MiR)-608 on the function of nonsmall cell lung cancer (NSCLC) A549 cells and related mechanisms.

METHODS

Blood samples of 106 NSCLC patients (experimental group) as well as 124 normal people (control group) were selected for relevant investigation. Polymerase chain reaction (PCR) as well as DNA sequencing was used to determine the genotyping of the MiR-608 rs4919510 polymorphism. MiR-608 expression in cells was detected by real-time PCR technology. Western blotting was used to detect changes in protein levels. NSCLC tissues as well as adjacent tissues were explored in 33 patients undergoing surgery.

RESULTS

MiR-608 rs4919510 does not influence the incidence of NSCLC patients. In addition, MiR-608 expression was downregulated in the tumor tissue of NSCLC patients, while the transcription factor activating enhancer-binding protein 4 (TFAP4) expression was upregulated. MiR-608 promotes DOX- (Doxorubicin-) induced apoptosis by negatively regulating TFAP4 expression in NSCLC tissue. TFAP4 can significantly inhibit the migration of A549 cells.

CONCLUSION

The findings in this investigation can contribute to the effective treatment of NSCLC patients. Also, the investigation can provide some theoretical support for the application of new targets for NSCLC treatment.

ZenoFishDb v1.1: A Database for Xenotransplantation Studies in Zebrafish

Rapidly accumulating literature has proven feasibility of the zebrafish xenograft models in cancer research. Nevertheless, online databases for searching the current zebrafish xenograft literature are in great demand. Herein, we have developed a manually curated database, called ZenoFishDb v1.1 (https://konulab.shinyapps.io/zenofishdb), based on R Shiny platform aiming to provide searchable information on ever increasing collection of zebrafish studies for cancer cell line transplantation and patient-derived xenografts (PDXs). ZenoFishDb v1.1 user interface contains four modules: DataTable, Visualization, PDX Details, and PDX Charts. The DataTable and Visualization pages represent xenograft study details, including injected cell lines, PDX injections, molecular modifications of cell lines, zebrafish strains, as well as technical aspects of the xenotransplantation procedures in table, bar, and/or pie chart formats. The PDX Details module provides comprehensive information on the patient details in table format and can be searched and visualized. Overall, ZenoFishDb v1.1 enables researchers to effectively search, list, and visualize different technical and biological attributes of zebrafish xenotransplantation studies particularly focusing on the new trends that make use of reporters, RNA interference, overexpression, or mutant gene constructs of transplanted cancer cells, stem cells, and PDXs, as well as distinguished host modifications.

Inhibitory effect of microRNA-608 on lung cancer cell proliferation, migration, and invasion by targeting BRD4 through the JAK2/STAT3 pathway

Lung cancer is the leading cause of cancer-related mortality around the world. This malignancy has a 5-year survival rate of 21%, because most of the patients are diagnosed in the middle or late stage of the disease when local metastasis and tumor invasion have already progressed. Therefore, the investigation of the pathogenesis of lung cancer is an issue of crucial importance. MicroRNAs (miRNAs) seem to be involved in the evolution and development of lung cancer. MicroRNA-608 is likely to be downregulated in lung cancer tissues. Regarding this, the current study involved the determination of the fundamental mechanism of microRNA-608 in the development of lung cancer. Based on the results of quantitative reverse transcription polymerase chain reaction (RT-qPCR), the expression level of microRNA-608 was downregulated in 40 lung cancer tissues, compared to that in the adjacent normal tissues. The results of dual-luciferase reporter assay revealed that bromodomain-containing protein 4 (BRD4) was the direct target of microRNA-608. Accordingly, the lung cancer tissues had an elevated expression level of BRD4, in contrast to the adjacent normal tissues. The results of Cell Counting Kit 8 assay demonstrated that the high expression of microRNA-608 notably restrained lung cancer cell proliferation. The scratch wound and transwell assays showed that the upregulation of microRNA-608 suppressed the migration and invasion of lung cancer cells. Finally, the western blot assay showed that in the microRNA-608 mimics group, the expression levels of BRD4, p-JAK2, p-STATA3, CD44, and MMP9 were significantly decreased, compared with those in the negative control miRNA mimics group. Our results indicate that high expression of microRNA-608 inhibits the proliferation, migration, and invasion of lung cancer cells by targeting BRD4 via the JAK2/STAT3 pathway.

Suppression of long noncoding RNA MALAT1 inhibits the development of uveal melanoma via microRNA-608-mediated inhibition of HOXC4

This study explored the effects of the metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) on the development of uveal melanoma. Moreover, the role of the MALAT1/microRNA-608 (miR-608)/homeobox C4 (HOXC4) axis was assessed by evaluating the proliferation, invasion, and migration, as well as the cell cycle distribution of uveal melanoma in vitro after knocking down MALAT1 or HOXC4 and/or overexpression of miR-608 in uveal melanoma cells (MUM-2B and C918). Moreover, the effects of the MALAT1/miR-608/HOXC4 axis in uveal melanoma in vivo were further evaluated by injecting the C918 cells into the NOD/SCID mice. HOXC4 was found to be a gene upregulated in uveal melanoma, while knockdown of its expression resulted in suppression of uveal melanoma cell migration, proliferation, and invasion, as well as cell cycle progression. In addition, the upregulation of miR-608 reduced the expression of HOXC4 in the uveal melanoma cells, which was rescued by overexpression of MALAT1. Hence, MALAT1 could upregulate the HOXC4 by binding to miR-608. The suppressed progression of uveal melanoma in vitro by miR-608 was rescued by overexpression of MALAT1. Additionally, in vivo assays demonstrated that downregulation of MALAT1 could suppress tumor growth through downregulation of HOXC4 expression via increasing miR-608 in uveal melanoma. In summary, MALAT1 downregulation functions to restrain the development of uveal melanoma via miR-608-mediated inhibition of HOXC4.

MicroRNA-608 promotes apoptosis via BRD4 downregulation in pancreatic ductal adenocarcinoma

The prognosis of pancreatic ductal adenocarcinoma (PDAC) remains poor even among patients with the same Tumor-Node-Metastasis stage. Thus, it is necessary to identify biomarkers that can accurately predict outcomes. There is accumulating evidence suggesting that microRNA (miR) expression influences overall survival (OS) time in patients with PDAC, via the regulation of tumor suppressor genes and oncogene expression. Specifically, miR-608 expression is hypothesized to regulate PDAC progression via the downregulation of bromodomain-containing protein 4 (BRD4) expression and the promotion of cell apoptosis. The present study aimed to investigate this theory. Thus, whole genome expression microarray analysis was performed on three patient samples with OS time >30 months, and compared with three samples with <12 months, in order to identify differentially expressed miRNAs (DEMs), via EdgeR analysis. A total of 591 DEMs were identified that exhibited a fold change >1, including 390 upregulated and 201 downregulated genes. Subsequently, 10 DEMs were identified using quantitative PCR in a different population of 68 tissues, collected from patients with PDAC. Notably, a high level of miRNA-608 expression was associated with longer OS times (P<0.05). Bioinformatics analysis was then performed to predict the molecular mechanism underlying the regulation of cell apoptosis by miRNA-608, and a dual-luciferase assay determined that overexpression of mimics in the Panc-1 and Bxpc-3 pancreatic cancer cell lines increased levels of apoptosis compared with the control. Additionally, high miRNA-608 expression decreased the protein level of BRD4. A luciferase reporting assay was used to elucidate whether miRNA-608 may directly inhibit the expression of BRD4 by binding to the 3′-untranslated region of its mRNA in the same cell lines. A subsequent rescue experiment indicated that the upregulation of BRD4 may reverse the apoptosis-promoting effect induced by miRNA-608. In summary, the present study revealed that miRNA-608 promotes apoptosis in PDAC via the negative regulation of BRD4. The results of the present study provide a theoretical basis that may improve the prediction of prognosis in patients with PDAC, and also indicate an opportunity to develop individualized treatment and investigate novel therapeutics that target these mechanisms.

RETRACTED: Long non-coding RNA LINC00052 regulates miR-608/EGFR axis to promote progression of head and neck squamous cell carcinoma

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the corresponding author and the Editor-in-chief The corresponding author claims that the authors confused multiple pictures in different groups, resulting in overlapping figures among different groups. Fig. 7B has partial overlap with Fig. 7D of a paper authored by a different research group (Y. Gao, et al., LINC00311 promotes cancer stem-like properties by targeting miR-330-5p/TLR4 pathway in human papillary thyroid cancer, Cancer Med. 9 (2019) 1515-1528, https://doi.org/10.1002/cam4.2815). The author claimed that they had sent the pathological sections to a shared platform and that the platform mistakenly sent back pathological results from other institutions which were then used in the manuscript. The Editor-in-Chief has lost the trust in the data and the conclusion, and decided to retract the paper.

LncRNA LOXL1-AS1 regulates the tumorigenesis and development of lung adenocarcinoma through sponging miR-423-5p and targeting MYBL2

Lung adenocarcinoma (LUAD) is the most common form of malignant tumor and closely correlated with high risk of death worldwide. Accumulating researches have manifested that long noncoding RNAs (lncRNAs) are deeply involved in the progression of multiple cancers. LncRNA LOXL1 antisense RNA 1 (LOXL1‐AS1) was identified as an oncogene in several cancers, nonetheless, its biological effect and regulatory mechanism have not been explained in LUAD. Our present study suggested that LOXL1‐AS1 expression was considerably increased in LUAD tissues and cells. Moreover, LOXL1‐AS1 deficiency notably hampered cell proliferation and migration as well as dramatically facilitated cell apoptosis. Through molecular mechanism assays, LOXL1‐AS1 was identified as a cytoplasmic RNA and acted as a sponge of miR‐423‐5p. Furthermore, MYBL2 was targeted and negatively modified by miR‐423‐5p. Rescue experiments revealed that MYBL2 knockdown could counteract miR‐423‐5p repression‐mediated enhancement on the progression of LOXL1‐AS1 downregulated LUAD cells. More importantly, MYBL2 was discovered to interact with LOXL1‐AS1 promoter, indicating a positive feedback loop of LOXL1‐AS1/miR‐423‐5p/MYBL2 in LUAD. These findings manifested the carcinogenic role of LOXL1‐AS1 and LOXL1‐AS1/miR‐423‐5p/MYBL2 feedback loop in LUAD, which could be helpful to explore effective therapeutic strategy for LUAD patients.

Upregulation of miR‑132‑3p in cholangiocarcinoma tissues: A study based on RT‑qPCR, The Cancer Genome Atlas miRNA sequencing, Gene Expression Omnibus microarray data and bioinformatics analyses

MicroRNAs (miRNAs/miRs) have been reported to be closely associated with numerous human diseases, including cholangiocarcinoma (CCA). However, the number of miRNAs known to be involved in CCA is limited, and the association between miR-132-3p and CCA remains unknown. In the present study, the clinical role of miR-132-3p and its potential signaling pathways were investigated by multiple approaches. Reverse transcription-quantitative PCR (RT-qPCR), CCA-associated Gene Expression Omnibus (GEO), ArrayExpress and Sequence Read Archive (SRA) miRNA-microarray or miRNA-sequencing data were screened, and meta-analyses were conducted, in order to calculate the receiver operating characteristic (ROC) curve and standardized mean difference (SMD). The predicted target genes of miR-132-3p were obtained from 12 online databases and were combined with the downregulated differentially expressed genes identified in the RNA-sequencing data of CCA. Gene Ontology annotation and pathway analysis were performed in WebGestalt. Protein-protein interaction analyses were conducted in STRING. The Cancer Genome Atlas (TCGA) mRNA expression profiles were used to validate the expression levels of hub genes at the mRNA level. The Human Protein Atlas was used to identify the protein expression levels of hub genes in CCA tissues and non-tumor biliary epithelium. The meta-analyses comprised 10 groups of RT-qPCR data, eight GEO microarray datasets and one TCGA miRNA-sequencing dataset. The SMD of miR-132-3p in CCA was 0.75 (95% CI: 0.25, 1.24), which indicated that miR-132-3p was overexpressed in CCA tissues. This finding was supported by a summary ROC value of 0.80 (95% CI: 0.76, 0.83). The pooled sensitivity and specificity were 0.81 (95% CI: 0.59, 0.93) and 0.71 (95% CI: 0.58, 0.81), respectively. The relative expression level of miR-132-3p in the early stage of CCA (stages I–II) was 6.8754±0.5279, which was markedly lower than that in the advanced stage (stages III–IVB), 7.3034±0.3267 (P=0.003). Consistently, the miR-132-3p level in low-grade CCA (grades G1-G2) was 6.7581±0.5297, whereas it was 7.1191±0.4651 in patients with high-grade CCA (grades G3-G4) (P=0.037). Furthermore, 555 potential target genes of miR-132-3p in CCA were mainly enriched in the ‘Focal Adhesion-PI3K-Akt-mTOR-signaling pathway’. In conclusion, upregulation of miR-132-3p may serve a pivotal role in the tumorigenesis and progression of CCA by targeting different pathways. Further in vitro and in vivo studies are required to support the current findings.

MicroRNA-608 Promotes Apoptosis in Non-Small Cell Lung Cancer Cells Treated With Doxorubicin Through the Inhibition of TFAP4

Lung cancer is the most commonly diagnosed type of cancer and the leading cause of cancer-associated death worldwide. MicroRNAs (miRNAs) are non-coding single-stranded RNA molecules of ∼20–25 nucleotides in length. Single nucleotide polymorphisms are a class of genetic variation in the human genome, which when present in miRNA genes are associated with the risk of developing cancer. This study aimed to identify whether the miRNA (miR)-608 polymorphism rs4919510 influenced the incidence of lung cancer, and to explore the underlying mechanisms of miR-608 in the pathogenesis of the disease. A total of 37 patients with non-small cell lung cancer (NSCLC) were selected to determine the expression levels of miR-608; 96 NSCLC patients and 136 cancer-free healthy controls were recruited to determine the incidence of miR-608 rs4919510 in lung cancer patients. Additionally, the impact of miR-608 on the expression of predicted target genes, cell migration, viability, proliferation, and apoptosis was also assessed. We found that the presence of miR-608 rs4919510 did not affect the susceptibility of patients to NSCLC or the maturation of miR-608. miR-608 expression levels were found to be downregulated in NSCLC tissues. Furthermore, overexpression of miR-608 promoted doxorubicin-induced apoptosis in NSCLC cell lines A549 and HCC4006 by inhibiting the expression of transcription factor activating enhancer-binding protein 4 (TFAP4), and high expression levels of TFAP4 were observed in NSCLC tissues. Therefore, our results may provide valuable insights for the chemotherapeutical treatment of NSCLC.

Nonconserved miR-608 suppresses prostate cancer progression through RAC2/PAK4/LIMK1 and BCL2L1/caspase-3 pathways by targeting the 3'-UTRs of RAC2/BCL2L1 and the coding region of PAK4

The aim of this study is to investigate the functions and mechanisms of miR-608 in prostate cancer (PCa). CISH and qRT-PCR analysis demonstrated that miR-608 was low expressed in PCa tissues and cells, which was partly attributed to the methylation of CpG island adjacent to the transcription start site (TSS) of miR-608 gene. Intracellular miR-608 overexpression inhibited in vivo PCa tumor growth, and suppressed PCa cell proliferation, G2/M transition, and migration in vitro, which was independent of EMT-associated mechanisms. Then RAC2, a GTPase previously deemed hematopoiesis-specific but now discovered to exist and play important roles in PCa, was verified by western blot and dual-luciferase reporter assays to mediate the effects of miR-608 through RAC2/PAK4/LIMK1/cofilin pathway. MiR-608 also promoted the apoptosis of PCa cells through BCL2L1/caspase-3 pathway by targeting the 3'-UTR of BCL2L1. Moreover, PAK4, the downstream effector of RAC2, was found to be targeted by miR-608 at the mRNA coding sequence (CDS) instead of the canonical 3'-UTR. Knocking down RAC2, PAK4, or BCL2L1 with siRNAs reproduced the antiproliferative, mitosis-obstructive, antimigratory and proapoptotic effects of miR-608 in PCa cells, which could be attenuated by downregulating miR-608. In conclusion, miR-608 suppresses PCa progression, and its activation provides a new therapeutic option for PCa.

CCN3 Facilitates Runx2 and Osterix Expression by Inhibiting miR-608 through PI3K/Akt Signaling in Osteoblasts

CCN3, otherwise known as the nephroblastoma overexpressed (NOV) protein, is a cysteine-rich protein that belongs to the CCN family and regulates several cellular functions. Osteoblasts are major bone-forming cells that undergo proliferation, mineralization, renewal, and repair during the bone formation process. We have previously reported that CCN3 increases bone morphogenetic protein 4 (BMP-4) production and bone mineralization in osteoblasts, although the role of CCN3 remains unclear with regard to osteogenic transcription factors (runt-related transcription factor 2 (Runx2) and osterix). Here, we used alizarin red-S and alkaline phosphatase staining to show that CCN3 enhances osteoblast differentiation. Stimulation of osteoblasts with CCN3 increases expression of osteogenic factors such as BMPs, Runx2, and osterix. Moreover, we found that the inhibition of miR-608 expression is involved in the effects of CCN3 and that incubation of osteoblasts with CCN3 promotes focal adhesion kinase (FAK) and Akt phosphorylation. Our results indicate that CCN3 promotes the expression of Runx2 and osterix in osteoblasts by inhibiting miR-608 expression via the FAK and Akt signaling pathways.

miR-608 and miR-4513 significantly contribute to the prognosis of lung adenocarcinoma treated with EGFR-TKIs

Tyrosine kinase inhibitors (TKIs) targeting epidermal growth factor receptors (EGFR) significantly prolong the survival of lung adenocarcinoma patients with sensitizing EGFR mutations. Unfortunately, 10-30% patients do not show objective responses to EGFR-TKIs, and undergo rapid disease progression during the EGFR-TKIs therapy. Single nucleotide polymorphisms (SNPs) in mature microRNA (miRNA) sequences may influence target site interactions and modulate downstream pathways, such as the EGFR pathway. For this reason, we hypothesized that miRNA SNPs may impact the prognosis of lung adenocarcinoma patients after EGFR-TKI treatment. By systematically screening of the miRbase and the 1000 genomes project databases, we successfully identified five mature miRNA SNPs. Genotypes were determined in two independent cohorts (Hubei and Shandong cohorts) that include 319 EGFR-TKI treated stage IIIB/IV patients. The impact of miR-608 and miR-4513 on the drug sensitivity of gefitinib was examined in lung adenocarcinoma cells. miR-608 rs4919510 or miR-4513 rs2168518 significantly contributed to the progression-free survival (PFS) in the Hubei cohort (hazard ratio [HR] = 0.63, confidence interval [CI] = 0.49-0.81, P = 3.0 × 10^-4 or HR = 0.46, 95% CI = 0.31-0.67, P = 8.0 × 10^-5). These observations were further validated in the Shandong cohort (P = 0.005 or P = 0.001). Similarly, the miR-608 rs4919510 CC genotype or the miR-4513 rs2168518 GA genotype was significantly associated with decreased death risk after gefitinib treatment, compared with the rs4919510 GG genotype (Hubei cohort: P = 5.0 × 10^-4; Shandong cohort: P = 0.004) or the rs2168518 GG genotype (P = 4.9 × 10^-5; P = 0.002). Consistently, miR-608 significantly increased the anti-proliferation effect of gefitinib in both lung adenocarcinoma PC9 and H1299 cells, whereas miR-4513 increased cells' resistance to gefitinib. Our findings suggest that miR-608 and miR-4513 SNPs are independent candidate biomarkers to predict lung adenocarcinoma patients' survival after EGFR-TKIs treatment. These miRNAs and polymorphisms provide clinical potential in patient-tailored treatment decision-making.

MiR-125b-1-3p Exerts Antitumor Functions in Lung Carcinoma Cells by Targeting S1PR1

Background

MicroRNAs (miRNAs) have been extensively studied over the decades and have been identified as potential molecular targets for cancer therapy. To date, many miRNAs have been found participating in the tumorigenesis of non-small cell lung cancer (NSCLC). The present study was designed to evaluate the functions of miR-125b-1-3p in NSCLC cells.

Methods

MiR-125b-1-3p expression was detected in tissue samples from 21 NSCLC patients and in NSCLC cell lines using the real-time polymerase chain reaction. A549 cell lines were transfected with a miR-125b-1-3p mimic or miR-125b-1-3p antisense. Cell counting kit-8, wound healing, Matrigel invasion assays, and flow cytometry were used to assess the effects of these transfections on cell growth, migration, invasion, and apoptosis, respectively. Western blotting was used to detect apoptosis-related proteins, expression of S1PR1, and the phosphorylation status of STAT3. Significant differences between groups were estimated using Student's t-test or a one-way analysis of variance.

Results

MiR-125b-1-3p was downregulated in NSCLC samples and cell lines. Overexpression of miR-125b-1-3p inhibited NSCLC cell proliferation (37.8 ± 9.1%, t = 3.191, P = 0.013), migration (42.3 ± 6.7%, t = 6.321, P = 0.003), and invasion (57.6 ± 11.3%, t = 4.112, P = 0.001) and simultaneously induced more NSCLC cell apoptosis (2.76 ± 0.78 folds, t = 3.772, P = 0.001). MiR-125b-1-3p antisense resulted in completely opposite results. S1PR1 was found as the target gene of miR-125b-1-3p. Overexpression of miR-125b-1-3p inhibited S1PR1 protein expression (27.4 ± 6.1% of control, t = 4.083, P = 0.007). In addition, S1PR1 siRNA decreased STAT3 phosphorylation (16.4 ± 0.14% of control, t = 3.023, P = 0.015), as in cells overexpressing miR-125b-1-3p (16.7 ± 0.17% of control, t = 4.162, P = 0.026).

Conclusion

Our results suggest that miR-125b-1-3p exerts antitumor functions in NSCLC cells by targeting S1PR1.

Prognostic implications of decreased microRNA-101-3p expression in patients with non-small cell lung cancer

To investigate the expression level of microRNA-101-3p (miR-101-3p) and its possible association with progression, prognosis and chemotherapy in patients with non-small cell lung cancer (NSCLC), the Gene Expression Omnibus (GEO) database was used. Quantitative polymerase chain reaction was used to verify the expression in 327 NSCLC and 42 adjacent normal lung tissues, of which 42 viable tissues were paired with nearby normal lung tissues. Based on the Cox regression model, univariate and multivariate analyses were used to address the factors that had effects on overall survival (OS) and disease-free survival (DFS) rate. Data from the GEO database demonstrated that the miR-101-3p expression in NSCLC was downregulated, compared with normal lung cancer. Survival analysis through univariate and multivariate models indicated that the miR-101-3p expression level was a crucial risk factor for OS and DFS in patients with NSCLC. A number of clinical parameters were determined to be associated with miR-101-3p expression, including tumor diameter, lymph node metastasis and tumor-node-metastasis stage. Adjuvant chemotherapy with high expression of miR-101-3p was determined to increase OS and DFS in patients with NSCLC, compared with patients with de novo or low expression of miR-101-3p. The present results demonstrated that miR-101-3p expression levels were associated with NSCLC progression and prognosis, which indicated that miR-101-3p may serve as a biomarker for patients with NSCLC who have received adjuvant chemotherapy.

microRNA-608 inhibits human hepatocellular carcinoma cell proliferation via targeting the BET family protein BRD4

Over-expression of the bromodomain and extraterminal (BET) family protein BRD4 is associated with hepatocellular carcinoma (HCC) progression. In the present study, we indentified a novel putative anti-BRD4 microRNA: microRNA-608 ("miR-608"). In HepG2 cells and primary human HCC cells, over-expression of miR-608, using a lentiviral construct, induced BRD4 downregulation and proliferation inhibition. Conversely, transfection of the miR-608 inhibitor increased BRD4 expression to promote HepG2 cell proliferation. Our results suggest that BRD4 is the primary target gene of miR-608 in HepG2 cells. shRNA-mediated knockdown or CRSIPR/Cas9-mediated knockout of BRD4 mimicked and overtook miR-608's actions in HepG2 cells. Furthermore, introduction of a 3'-untranslated region (3'-UTR) mutant BRD4 (UTR-A1718G) blocked miR-608-induced c-Myc downregulation and proliferation inhibition in HepG2 cells. In vivo, HepG2 xenograft tumor growth was significantly inhibited after expressing miR-608 or BRD4 CRSIPR/Cas9-KO construct. Importantly, BRD4 mRNA was upregulated in human HCC tissues, which was correlated with downregulation of miR-608. Together, we conclude that miR-608 inhibits HCC cell proliferation possibly via targeting BET family protein BRD4.

Role of upregulated miR-136-5p in lung adenocarcinoma: A study of 1242 samples utilizing bioinformatics analysis

BACKGROUND

It is generally acknowledged that miRNAs play pivotal roles in the initiation and development of cancer. The aim of the current study is to investigate the clinicopathological role of miR-136-5p in lung adenocarcinoma and its underlying molecular mechanism.

MATERIALS AND METHODS

Data of a cohort of 1242 samples were provided by the Gene Expression Omnibus and The Cancer Genome Atlas to evaluate miR-136-5p expression in lung adenocarcinoma. A comprehensive meta-analysis integrating the expression data from all sources was performed, followed by a summary receiver operating curve plotted to appraise the upregulated expression of miR-136-5p in lung adenocarcinoma. Candidate targets of miR-136-5p were launched by the intersection of differentially expressed genes in The Cancer Genome Atlas and genes predicted by 12 web-based platforms. Then, hub genes were illustrated by a protein-protein interaction network. Furthermore, Kyoto Encyclopedia of Genes and Genomes, Gene Ontology and Protein Analysis Through Evolutionary Relationships analyses of potential target genes were carried out via bioinformatics tools.

RESULTS

MiR-136-5p expression was upregulated in lung adenocarcinoma versus normal tissues (standard mean difference = 0.43, 95% confidence interval: 0.27-0.58). The summary receiver operating characteristic curve further verified the upregulation of miR-136-5p in lung adenocarcinoma (area under curve = 0.7459). A total of 311 candidate target genes of miR-136-5p were gathered to create a protein-protein interaction network. Molecular mechanism analysis unveiled the potential miR-136-5p target genes participated in cell adhesion molecules, focal adhesion, complement and coagulation cascades and blood coagulation.

CONCLUSION

MiR-136-5p is overexpressed in lung adenocarcinoma and is involved in the molecular mechanism of lung adenocarcinoma via suppressing the expressions of downstream targets, especially claudin-18, sialophorin and syndecan 2 that participate in cell adhesion.