MicroRNA-588 suppresses tumor cell migration and invasion by targeting GRN in lung squamous cell carcinoma

Significance of NKX2-1 as a biomarker for clinical prognosis, immune infiltration, and drug therapy in lung squamous cell carcinoma

Background

This study was performed to determine the biological processes in which NKX2-1 is involved and thus its role in the development of lung squamous cell carcinoma (LUSC) toward improving the prognosis and treatment of LUSC.

Methods

Raw RNA sequencing (RNA-seq) data of LUSC from The Cancer Genome Atlas (TCGA) were used in bioinformatics analysis to characterize NKX2-1 expression levels in tumor and normal tissues. Survival analysis of Kaplan-Meier curve, the time-dependent receiver operating characteristic (ROC) curve, and a nomogram were used to analyze the prognosis value of NKX2-1 for LUSC in terms of overall survival (OS) and progression-free survival (PFS). Then, differentially expressed genes (DEGs) were identified, and Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and Gene Set Enrichment Analysis (GSEA) were used to clarify the biological mechanisms potentially involved in the development of LUSC. Moreover, the correlation between the NKX2-1 expression level and tumor mutation burden (TMB), tumor microenvironment (TME), and immune cell infiltration revealed that NKX2-1 participates in the development of LUSC. Finally, we studied the effects of NKX2-1 on drug therapy. To validate the protein and gene expression levels of NKX2-1 in LUSC, we employed immunohistochemistry(IHC) datasets, The Gene Expression Omnibus (GEO) database, and qRT-PCR analysis.

Results

NKX2-1 expression levels were significantly lower in LUSC than in normal lung tissue. It significantly differed in gender, stage and N classification. The survival analysis revealed that high expression of NKX2-1 had shorter OS and PFS in LUSC. The multivariate Cox regression hazard model showed the NKX2-1 expression as an independent prognostic factor. Then, the nomogram predicted LUSC prognosis. There are 51 upregulated DEGs and 49 downregulated DEGs in the NKX2-1 high-level groups. GO, KEGG and GSEA analysis revealed that DEGs were enriched in cell cycle and DNA replication.The TME results show that NKX2-1 expression was positively associated with mast cells resting, neutrophils, monocytes, T cells CD4 memory resting, and M2 macrophages but negatively associated with M1 macrophages. The TMB correlated negatively with NKX2-1 expression. The pharmacotherapy had great sensitivity in the NKX2-1 low-level group, the immunotherapy is no significant difference in the NKX2-1 low-level and high-level groups. The analysis of GEO data demonstrated concurrence with TCGA results. IHC revealed NKX2-1 protein expression in tumor tissues of both LUAD and LUSC. Meanwhile qRT-PCR analysis indicated a significantly lower NKX2-1 expression level in LUSC compared to LUAD. These qRT-PCR findings were consistent with co-expression analysis of NKX2-1.

Conclusion

We conclude that NKX2-1 is a potential biomarker for prognosis and treatment LUSC. A new insights of NKX2-1 in LUSC is still needed further research.

Tumor microenvironment characteristics and prognostic role of m6A modification in lung squamous cell carcinoma

Background

It has recently been determined that N6-methyladenosine (m6A) RNA methylation regulators have prominent effects on several cancers. However, the potential role of m6A modification in lung squamous cell carcinoma (LUSC) remains unclear.

Methods

We evaluated the modification pattern of m6A and studied the biological function of m6A regulators in LUSC. Then, we constructed the m6Ascore to predict the prognosis of LUSC and analyzed the relationship between the m6Ascore and tumor mutation burden, immune cell infiltration, and immunotherapy.

Result

In the unsupervised consensus cluster analysis, three different m6Aclusters were identified, which correspond to an immune activation state, a moderate immune activation state, and an immune tolerance state. Forty-two genes related to the m6A phenotype were used to construct the m6Ascore; subsequently, multiple validations of the m6Ascore were carried out to determine the relationship between the score and immune cell infiltration and response to CTLA-4/PD-1 inhibitor treatment. Further analysis revealed that the m6Ascore could effectively predict the prognosis of LUSC and that the m6A phenotype-related genes, FAM162A and LOM4, might be potential biomarkers.

Conclusion

These findings highlight the potential role of m6A modification in the prognosis, TME, and immunotherapy of LUSC and have profound implications for developing more effective personalized treatment strategies for LUSC.

Establishment of a prognostic model toward lung squamous cell carcinoma based on m7G-related genes in the cancer genome atlas

Lung squamous cell carcinoma (LUSC) is a non-small cell lung cancer with a poor prognosis owing to late diagnosis. New molecular markers are urgently needed to improve the diagnosis and prognosis of LUSC. 7-Methylguanosine (m7G) modifications, a tRNA modification, are common in eubacteria, eukaryotes, and a few archaea. These modifications promote the turnover and stability of some mRNAs to prevent mRNA decay, improve translation efficiency, and reduce ribosomal pausing but are associated with poor survival in human cancer cells. However, expression of m7G-related genes in LUSC and their association with prognosis remain unclear. In the present study, we identified nine differentially expressed genes related to prognosis by comparing the expression profiles of tumor tissues (502 LUSC reports) with normal tissues (49 adjacent nontumor lung tissue reports). The genes included six upregulated genes (KLK7, LCE3E, AREG, KLK6, ZBED2, and MAPK4) and three downregulated genes (ADH1C, NTS, and ERLIN2). Based on these nine genes, patients with LUSC were classified into low- and high-risk groups to analyze the trends in prognosis. We found that the nine m7G-related genes play important roles in immune regulation, hormone regulation, and drug sensitivity through pathways including antigen processing and presentation, adherent plaques, extracellular matrix receptor interactions, drug metabolism of cytochrome P-450, and metabolism of cytochrome P-450 to xenobiotics; the functions of these genes are likely accomplished in part by m6A modifications. The effect of m7G-related genes on the diagnosis and prognosis of LUSC was further indicated by population analysis.NEW & NOTEWORTHY Based on the differential expression of 7-methylguanosine (m7G) modification-associated genes between normal and lung squamous cell carcinoma (LUSC) tissues, and considering the performance of our m7G-related gene risk profiles as independent risk factors in predicting overall survival, we conclude that m7G modification is closely linked to the development of LUSC. In addition, this study offers a new genetic marker for predicting the prognosis of patients with LUSC and presents a crucial theoretical foundation for future investigations on the relationship between m7G modification-related genes, immunity, and drug sensitivity in LUSC.

MiR-101-3p targets KPNA2 to inhibit the progression of lung squamous cell carcinoma cell lines

We herein discuss the impacts of miR-101-3p on the tumorigenesis-related cell behaviors in lung squamous cell carcinoma (LUSC) by repressing KPNA2. TCGA database was utilized to measure miR-101-3p and KPNA2 levels in LUSC tissues and cells. The interaction of miR-101-3p and KPNA2-3'UTR was determined by dual luciferase assay. Western blot evaluated the protein level of KPNA2. MiR-101-3p was under-expressed in LUSC cells while KPNA2 was overexpressed. Western blot confirmed the impact of KPNA2 expression on cancer cell progression. The negative regulatory impact of miR-101-3p on KPNA2 was also verified. In vitro cell function assays revealed the suppressing effect of high miR-101-3p expression on cell invasion, migration and viability, as well as its promoting effect on apoptosis. Up-regulated miR-101-3p weakened the promoting effect of overexpressed KPNA2 on LUSC malignant progression. To conclude, miR-101-3p repressed viability, invasion, and migration, and facilitated cell apoptosis in LUSC by suppressing KPNA2.

MicroRNA-588 regulates the invasive, migratory and vasculogenic mimicry-forming abilities of hypoxic glioma cells by targeting ROBO1

BACKGROUND

The microenvironment of hypoxia is an important factor contributing to the development of glioblastoma (GBM). MicroRNA-588 and its potential target Roundabout-directed receptor 1 (ROBO1) have been reported to promote tumor invasion and proliferation in diseases such as gastric, pancreatic and hepatocellular carcinoma, while their function in GBM and response to hypoxic states remain elusive.

METHODS

A microarray was leveraged to identify differentially expressed microRNAs in U251 glioma cells cultured under normoxic and hypoxic conditions. The expression of miR-588 was assessed using quantitative real-time PCR (qRT‒PCR). Gain- and loss-of-function studies were used to evaluate the role of miR-588 under hypoxic and normoxic conditions. Cell invasion, migration, proliferation, and vasculogenic mimicry (VM) formation experiments were performed. The relationship between miR-588 and ROBO1 was confirmed using western blot and luciferase reporter assays. Intracranial xenograft tumor mouse models were used to study the function of miR-588 in vivo.

RESULTS

The expression of miR-588 was significantly upregulated in hypoxic glioma cells relative to normoxic glioma cells. miR-588 inhibited the invasive, migratory and VM-forming abilities of glioma cells in vitro and in vivo. Mechanistically, roundabout guidance receptor 1 (ROBO1) is a direct, functionally relevant target of miR-588 in glioma. ROBO1 knockdown suppressed the expression of matrix metallopeptidase 2 (MMP2) and matrix metallopeptidase 9 (MMP9), thereby inhibiting the invasive, migratory and VM-forming abilities of glioma.

CONCLUSIONS

MiR-588 regulated the behaviors of hypoxic glioma cells by targeting ROBO1. miR-588 can be used as a prognostic marker for glioma and has potential implications in glioma gene therapy.

Can serum progranulin level be used as a prognostic biomarker in non-small cell lung cancer?

Progranulin has been considered to be a poor prognostic biomarker for some types of malignancies. However, the clinical significance of serum progranulin level and the prognostic value are still not explored in advanced stages of lung cancer.  The current study investigates the prognostic significance of progranulin serum levels in advanced-stage non-small cell lung cancer (NSCLC) patients. This study involved 94 subjects (70 advanced-stage NSCLC patients and 24 healthy controls). Serum progranulin level was measured by enzyme-linked immunosorbent assay (ELISA) and was correlated with patient outcome. The association between circulating progranulin level and clinicopathological parameters was detected. Serum progranulin cut-off level predicting six-month survival was determined. Serum progranulin level was found significantly elevated in NSCLC patients than in the control group (p<0.001). We did not determine a significant difference between stage IIIB and stage IV NSCLC patients for serum progranulin levels (p=0.166). When we evaluated the laboratory parameters, only serum LDH level was found significantly correlated with serum progranulin level (p=0.043), also bone and liver metastasis showed a significant correlation with progranulin level (p=0.008 and p = 0.024, respectively). The cut-off level of serum progranulin in predicting six months of survival was determined as 16.03 ng/ml (AUC = 0.973, 95%Cl: 0.903-0.997, p<0.001) with 97.06% sensitivity and 88.89% specificity. Overall survival was determined shorter in patients with progranulin level ≥16 ng/ml than those with <16 ng/ml (p<0.001). Also, in the multivariate analysis using the Cox regression model serum progranulin level was found as an independent prognostic factor for NSCLC (p=0.001). Serum progranulin level may be a useful biomarker for predicting poor survival in advanced-stage NSCLC patients.

Circ_0010235 Regulates HOXA10 Expression to Promote Malignant Phenotypes and Radioresistance in Non-small Cell Lung Cancer Cells Via Decoying miR-588

Background:

Circular RNAs (circRNAs) are key modulators in carcinogenesis and radioresistance in multiple kinds of human cancers.

Aims:

To explore the role of circ_0010235 in non-small cell lung cancer (NSCLC).

Study Design:

Cell culture study and animal study.

Methods:

The detection of circ_0010235, microRNA-588 (miR-588), and homeobox protein A10 (HOXA10) was implemented via reverse transcription-quantitative polymerase chain reaction (RT-qPCR). CCK-8, EdU, flow cytometry, transwell, and wound healing assays. These strategies were applied to evaluate cell functions. The western blot technique was employed for protein examination. The colony formation assay was used to determine cell survival after radiation treatment. In vivo research was performed by tumor xenograft assay. The binding analysis was also carried out through dual-luciferase reporter and RNA immunoprecipitation studies.

Results:

Circ_0010235 had an enhanced expression in NSCLC. Circ_0010235 deficiency inhibited cell proliferation, invasiveness, and migratory ability but promoted apoptosis and radiosensitivity. Downregulation of circ_0010235 decelerated tumor growth and promoted radiation sensitivity in vivo. Circ_0010235 was controlled biologically in NSCLC cells by combining with miR-588 and targeting miR-588. HOXA10 acted as a target of miR-588. MiR-588 upregulation inhibited NSCLC cell malignant phenotypes and elevated radiosensitivity via downregulating HOXA10. Circ_0010235 could regulate the level of HOXA10 by sponging miR-588.

Conclusion:

Circ_0010235 contributed to the malignant progression of NSCLC, but suppressed the radiation sensitivity via targeting miR-588 to induce HOXA10 upregulation.

N6-Methyladenosine-Related Long Non-Coding RNAs Are Identified as a Potential Prognostic Biomarker for Lung Squamous Cell Carcinoma and Validated by Real-Time PCR

Currently, the precise mechanism by which N6-methyladenosine (m6A) modification of long non-coding RNAs (lncRNAs) promotes the occurrence and development of lung squamous cell carcinoma (LUSC) and influences tumor microenvironment (TME) remains unclear. Therefore, we studied the prognostic value of m6A-related lncRNAs and their relationship with TME in 495 LUSC samples from The Cancer Genome Atlas (TCGA) database. Pearson’s correlation and univariate Cox regression analysis identified 6 m6A-related lncRNAs with prognostic values for LUSC patients. LUSC patients were divided into two subgroups (clusters 1 and 2) using principal component analysis. The expression of PD-L1 was lower in tumor tissues and cluster 2 of LUSC patients. Cluster 2 of LUSC patients had a high immune score, stromal score, and unique immune cell infiltration. The focal adhesion kinase (FAK) pathway and cytokine receptor pathways are enriched in cluster 1. The m6A-related lncRNA prognostic markers (m6A-LPMs) were established using the least absolute shrinkage and selection operator (LASSO) Cox regression analysis. The risk score was calculated by 4 m6A-LPMs and associated with OS, TME, clinicopathological characteristics of LUSC patients. After adjusting for age, gender, and stage, the risk score was also an independent prognostic factor for LUSC patients. Real-time PCR results showed that the expression of 4 m6A-LPMs was consistent with our prediction results. Our study found that 4 m6A-LPMs (AC138035.1, AC243919.2, HORMAD2-AS1, and AL122125.1) are closely associated with LUSC prognosis, in future, they may as novel diagnostic biomarkers for LUSC and provide new immunotherapy targets for LUSC patients.

LncRNA ZFAS1 regulates the proliferation, oxidative stress, fibrosis, and inflammation of high glucose-induced human mesangial cells via the miR-588/ROCK1 axis

BACKGROUND

Diabetic nephropathy (DN) is a critical and the most common microvascular complication and its pathogenesis is still faintly understood. Thus, this study was performed to examine the long non-coding RNA ZNFX1 Antisense Gene Protein 1 (lncRNA ZFAS1) biological function and mechanism of regulation in DN.

METHOD

Human glomerular mesangial cells (HGMC) were induced with high glucose (HG, 25 mM) to establish HG-induced cell viability, pro-inflammation observed in DN. After, target miRNA and mRNA were predicted through Lncbase and Targetscan. Subsequently, the expression of ZFAS1, miR-588, and ROCK1 in DN clinical samples and cell-model was examined through qRT-PCR and western blot analysis. We upheld the targeted interaction between miR-588 and ZFAS1 or ROCK1 through a dual-luciferase reporter assay. The proliferation of the cell was also examined through CCK-8 assay, while the level of HG-induced oxidative stress was established by measuring reactive oxygen species (ROS) level, and also the activities of antioxidant enzymes in the cell. Lastly, the level of accumulated extracellular matrix (ECM) protein-fibronectin and collagen type IV, and inflammatory cytokines produced by the cell was analyzed through western blot analysis and ELISA.

RESULTS

ZFAS1 was significantly upregulated in the DN blood samples and HG-induced HGMC. Prediction result revealed that the ZFAS1 endogenously targets the miR-588 seed sequence while miR-588 plays a role in post-transcriptional regulation of ROCK1 mRNA. Moreover, we found that miR-588 expression was significantly downregulated in DN blood samples and negatively correlates with ZFAS1 expression. Further results show that silencing ZFAS1 had a protective effect on HG-induced proliferation, oxidative stress, fibrosis, and inflammation in HGMC while miR-588 inhibition and ROCK1 overexpression reversed this effect.

CONCLUSIONS

Altogether, our data suggest that ZFAS1 regulates the proliferation, oxidative stress, fibrosis, and inflammation of high glucose-induced diabetic nephropathy through the miR-588/ROCK1 axis.

SNHG8 promotes cell proliferation, migration, and invasion of nasopharyngeal carcinoma cells as an oncogene through miR-588/HMGA2 axis

Nasopharyngeal carcinoma (NC) poses a threat to the life of patients. Long non-coding RNA (LncRNA) is a novel kind of non-coding RNA, which plays a pivotal role through sponge microRNA (miRNA). Abnormal expression of small nucleolar RNA host gene 8 (SNHG8) is involved in various tumors; however, the role of SNHG8 in NC remains unknown. Quantitative real-time PCR (qRT-PCR) and Western blotting was employed to detect the expression levels of SNHG8, miR-588, and high mobility group A2 (HMGA2). Cell proliferation, migration, and invasion were analyzed by CCK-8 and transwell assays. miR-588 binding sites in SNHG8 were predicted by LncBase analysis. Luciferase reporter and RNA pull-down assay were used to confirm the interaction of SNHG8 and miR-588. SNHG8 was highly expressed in NC cells. The prognosis of the patients with NC in the high expression levels of SNHG8 was poorer than that in the low expression levels. The expression of SNHG8 was closely related to tumor size, TNM stage, and distal metastasis. Knockdown of SNHG8 inhibited cell proliferation, migration, and invasion of NC. SNHG8 targeted miR-588. Inhibition of miR-588 could partially reverse the knockdown of SNHG8 in NC cells, and miR-588 targeted HMGA2. In conclusion, SNHG8 promotes proliferation, migration, and invasion of NC cells through miR-588/HMGA2 in NC as an oncogene.

Plasma circN4BP2L2 is a promising novel diagnostic biomarker for epithelial ovarian cancer

BACKGROUND

Circular RNAs (circRNAs) are more stable than linear RNA molecules, which makes them promising diagnostic biomarkers for diseases. By circRNA-sequencing analysis, we previously found that circN4BP2L2 was significantly decreased in epithelial ovarian cancer (EOC) tissues, and was predictive of disease progression. The aim of this study was to evaluate the diagnostic value of plasma circN4BP2L2 in EOC.

METHODS

Three hundred seventy-eight plasma samples were acquired prior to surgery. Samples were obtained from 126 EOC patients, 126 benign ovarian cyst patients, and 126 healthy volunteers. CircN4BP2L2 was assessed using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Cancer antigen 125 (CA125) and human epididymis protein 4 (HE4) were assessed using enzyme-linked immunosorbent assay (ELISA). EOC cells were transfected with small interference RNAs (siRNAs) and cell proliferation, migration, invasion, cell cycle and cell apoptosis were performed to assess the effect of circN4BP2L2 in EOC. Receiver operating curve (ROC), the area under the curve (AUC), sensitivity and specificity were estimated.

RESULTS

Plasma circN4BP2L2 was significantly downregulated in EOC patients. Decreased circN4BP2L2 was significantly associated with advanced tumor stage, worse histological grade, lymph node metastasis and distant metastasis in EOC. CircN4BP2L2 inhibited tumor cell migration and invasion in vitro. CircN4BP2L2 could significantly separate EOC from benign (AUC = 0.82, P <  0.01) or normal (AUC = 0.90, P <  0.01) cohort. Early stage EOC vs benign (AUC = 0.81, P <  0.01) or normal (AUC = 0.90, P <  0.01) cohort could also be distinguished by circN4BP2L2. In discrimination between EOC cohort and benign or normal cohort, circN4BP2L2 performed equally well in both pre- and post-menopausal women. The combination of circN4BP2L2, CA125 and HE4 showed high sensitivity and specificity in detecting EOC cases.

CONCLUSIONS

Plasma circN4BP2L2 is significantly downregulated in EOC and might serve as a promising novel diagnostic biomarker for EOC patients, especially in early stage EOC cases. CircN4BP2L2 might act as an adjunct to CA125 and HE4 in detecting EOC. Further large-scale studies are warranted to verify our results.

Mining sponge phenomena in RNA expression data

In the last few years, the interactions among competing endogenous RNAs (ceRNAs) have been recognized as a key post-transcriptional regulatory mechanism in cell differentiation, tissue development, and disease. Notably, such sponge phenomena substracting active microRNAs from their silencing targets have been recognized as having a potential oncosuppressive, or oncogenic, role in several cancer types. Hence, the ability to predict sponges from the analysis of large expression data sets (e.g. from international cancer projects) has become an important data mining task in bioinformatics. We present a technique designed to mine sponge phenomena whose presence or absence may discriminate between healthy and unhealthy populations of samples in tumoral or normal expression data sets, thus providing lists of candidates potentially relevant in the pathology. With this aim, we search for pairs of elements acting as ceRNA for a given miRNA, namely, we aim at discovering miRNA-RNA pairs involved in phenomena which are clearly present in one population and almost absent in the other one. The results on tumoral expression data, concerning five different cancer types, confirmed the effectiveness of the approach in mining interesting knowledge. Indeed, 32 out of 33 miRNAs and 22 out of 25 protein-coding genes identified as top scoring in our analysis are corroborated by having been similarly associated with cancer processes in independent studies. In fact, the subset of miRNAs selected by the sponge analysis results in a significant enrichment of annotation for the KEGG32 pathway "microRNAs in cancer" when tested with the commonly used bioinformatic resource DAVID. Moreover, often the cancer datasets where our sponge analysis identified a miRNA as top scoring match the one reported already in the pertaining literature.

Gene Expression Profiling of Tricarboxylic Acid Cycle and One Carbon Metabolism Related Genes for Prognostic Risk Signature of Colon Carcinoma

Colorectal cancer (CRC) is one of the most prevalent malignant tumors worldwide. Colon adenocarcinoma (COAD) is the most common pathological type of CRC and several biomarkers related to survival have been confirmed. Yet, the predictive effect of a single gene biomarker is not enough. The tricarboxylic acid (TCA) cycle and carbon metabolism play an important role in tumors. Thus, we aimed to identify new gene signatures from the TCA cycle and carbon metabolism to better predict the survival of COAD. This study performed mRNA expression profiling in large COAD cohorts (n = 417) from The Cancer Genome Atlas (TCGA) database. Univariate Cox regression and multivariate Cox regression analysis were performed, and receiver operating characteristic (ROC) curve was used to screen the variable combinations model which is most relevant to patient prognosis survival mostly. Univariable or multivariate analysis results showed that SUCLG2, SUCLG1, ACLY, SUCLG2P2, ATIC and ACO2 have associations with survival in COAD. Combined with clinical variables, we confirmed model 1 (AUC = 0.82505), most relevant to patient prognosis survival. Model 1 contains three genes: SUCLG2P2, SUCLG2 and ATIC, in which SUCLG2P2 and SUCLG2 were low-expressed in COAD, however, ATIC was highly expressed, and the expressions above are related to stages of CRC. Pearson analysis showed that SUCLG2P2, SUCLG2 and ATIC were correlated in normal COAD tissues, while only SUCLG2P2 and SUCLG2 were correlated in tumor tissues. Finally, we verified the expressions of these three genes in COAD samples. Our study revealed a possible connection between the TCA cycle and carbon metabolism and prognosis and showed a TCA cycle and carbon metabolism related gene signature which could better predict survival in COAD patients.

Comprehensive network analysis of different subtypes of molecular disorders in lung cancer

Lung cancer is the leading cause of cancer-related death worldwide. In this study, we attempted to identify the common pathogenesis of lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) based on a modular and comprehensive analysis method. Data were downloaded and the differences analyzed in LUAD samples, LUSC samples, and normal samples, respectively. Co-expression analysis, enrichment analysis, and hypergeometric testing were used to predict transcription factors (TFs) and ncRNAs, as well as target genes. We obtained 4,596 differentially expressed genes which were clustered into 14 modules dysfunction. The 14 clustered genes (including DOK2, COL5A1, and TSPAN8) were identified as the core genes of the module. Module genes are substantially involved in biological processes, such as extracellular matrix, carbohydrate binding and renal system development, and signal transduction as well, including PPAR signal transduction, cGMP-PKG signal transduction, PI3K-Akt signal transduction, and Apelin signal transduction. We identified ncRNA (miR-335-5p, ANCR, TUG1) and transcription factors (RELA, SP1) to regulate dysfunction module genes essentially. The analysis showed that comprehensive co-expression analysis contributes to understanding the TF ncRNA. Moreover, it assisted in further understanding of the molecular pathogenesis of co-expression of modular genes that regulate LUAD and LUSC. It provided a precious resource and theoretical basis for further experiments.

Long non-coding RNA SNHG8 promotes autophagy as a ceRNA to upregulate ATG7 by sponging microRNA-588 in colorectal cancer

Colorectal cancer (CRC) is the third most common cancer worldwide. Long non-coding RNA (lncRNA) small nucleolar RNA host gene 8 (SNHG8) acts as an oncogene in different types of cancer, including prostate, breast and ovarian cancer. SNHG8 promotes the tumorigenesis of CRC; however, its underlying molecular mechanism remains unclear. The present study aimed to explore the mechanism of SNHG8 on CRC development via various assays, including western blot, pull-down, PCR and immunofluorescence assays. The results of the present study demonstrated that SNHG8 expression was substantially upregulated in primary tumor tissues from The Cancer Genome Atlas dataset. Western blot and immunofluorescence analyses demonstrated that SNHG8 facilitated cell proliferation and autophagy in CRC cells. Notably, the function of SNHG8 in enhancing autophagy was dependent on autophagy-related gene 7 (ATG7). In addition, western blot analysis indicated that the effect of SNHG8 on autophagy in CRC cells was dependent on the miR-588/ATG7 axis. Taken together, the results of the present study suggest that SNHG8 promotes autophagy in CRC cells.

Circular RNA ABCB10 contributes to laryngeal squamous cell carcinoma (LSCC) progression by modulating the miR-588/CXCR4 axis

Laryngeal squamous cell carcinoma (LSCC) is a common head and neck cancer with a high metastasis and poor prognosis. Circular RNAs (circRNAs) are a type of non-coding RNAs (ncRNAs) with regulatory function and broadly participate in cancer development. However, the correlation of circular RNA ABCB10 (circABCB10) with LSCC remains unclear. Here, we were interested in the role of circABCB10 in the modulation of LSCC progression. Our data demonstrated that the depletion of circABCB10 significantly inhibited the proliferation and induced the apoptosis of LSCC cells. Meanwhile, circABCB10 knockdown was able to remarkably reduce the invasion and migration of LSCC cells. Mechanically, circABCB10 served as a sponge for microRNAs-588 (miR-588) and miR-588 could target and down-regulated chemokine receptor 4 (CXCR4) expression in LSCC cells. The overexpression of CXCR4 or miR-588 inhibitor could reverse circABCB10 depletion-attenuated malignant phenotypes of LSCC cells. Functionally, the depletion of circABCB10 alleviated the tumor growth of LSCC cells in the tumorigenicity analysis of nude mice. The CXCR4 expression was decreased while the miR-588 expression was enhanced by circABCB10 depletion in vivo. Thus, we concluded that circABCB10 was involved in the malignant progression of LSCC by regulating miR-588/CXCR4 axis. Our finding provides new insights into the mechanism of circRHOT1 contributing to the development of LSCC. CircABCB10 and miR-588 may be used as potential targets for the treatment of LSCC.

Downregulation of miR-588 is associated with tumor progression and unfavorable prognosis in patients with osteosarcoma

Osteosarcoma (OS) is a primary malignant tumor characterized by a high metastatic potential and poor prognosis. The dysregulation of miR-588 has been demonstrated to serve crucial roles in the progression of numerous types of cancer. The present study aimed to investigate the expression and function of miR-588 in the development of OS. To do so, clinical samples were collected and analyzed, and in vitro experiments were conducted. A total of 104 patients with OS were recruited between 2012 and 2014. The expression of miR-588 was analyzed by reverse transcription quantitative PCR. The association between miR-588 expression and the clinicopathological characteristics and survival rate of patients with OS was evaluated. Furthermore, Cell Counting Kit-8 and Transwell assays were used to evaluate the effect of miR-588 on the proliferation and the migratory and invasive abilities of various OS cell lines. The results demonstrated that miR-588 expression in OS tissues and cells was significantly lower compared with normal tissues and cells. In addition, miR-588 expression was closely associated with the Musculoskeletal Tumor Society (MSTS) staging of patients with OS. miR-588 expression and MSTS staging were therefore considered as independent indicators for the prognosis of patients with OS. In addition, miR-588 downregulation significantly stimulated the proliferation and migratory and invasive abilities of OS cells. Taken together, these findings indicated that miR-588 may serve as an independent prognostic factor and tumor suppressor in OS.

The Impact of Air Pollution Exposure on the MicroRNA Machinery and Lung Cancer Development

Small non-coding RNA molecules (miRNAs) play an important role in the epigenetic regulation of gene expression. As these molecules have been repeatedly implicated in human cancers, they have been suggested as biomarkers of the disease. Additionally, miRNA levels have been shown to be affected by environmental pollutants, including airborne contaminants. In this review, we searched the current literature for miRNAs involved in lung cancer, as well as miRNAs deregulated as a result of exposure to air pollutants. We then performed a synthesis of the data and identified those molecules commonly deregulated under both conditions. We detected a total of 25 miRNAs meeting the criteria, among them, miR-222, miR-21, miR-126-3p, miR-155 and miR-425 being the most prominent. We propose these miRNAs as biomarkers of choice for the identification of human populations exposed to air pollution with a significant risk of developing lung cancer.

miR-588 is a prognostic marker in gastric cancer

In an effort to identify a novel microRNA (miRNA) as a gastric cancer (GC) treatment target and prognostic biomarker, we surveyed The Cancer Genome Atlas database and found that miR-588 expression is low in GC tissues. This was confirmed by real-time reverse transcription polymerase chain reaction assays of GC patient plasma samples and SGC7901 and MNK28 cells. A constructed miRNA-mRNA network showed that CXCL5, CXCL9, and CXCL10 are target genes of miR-588. Analysis of the miRWalk database revealed that miR-588 directly binds to CXCL5 and CXCL9. Overexpression of miR-588 reduced GC cell proliferation in vitro and in vivo. High expression of miR-588 inhibited Ki-67 expression in vivo. The FunRich database also showed that CXCL5, CXCL9, and CXCL10 are involved in immune responses, while the Database of Immune Cell Expression showed they are differentially expressed in CD8+ T cells. High expression of CXCL9 and CXCL10 correlated positively with infiltrating levels of CD4+ T and CD8+ T cells in stomach adenocarcinoma. High expression of miR-588, CXCL5, CXCL9, and CXCL10 was associated with prolonged survival of GC patients. These findings indicate that miR-588 is a biomarker for tumor-associated immune infiltration and a prognostic marker in GC patients.

Enrichment of Up-regulated and Down-regulated Gene Clusters Using Gene Ontology, miRNAs and lncRNAs in Colorectal Cancer

AIM AND OBJECTIVE

It is interesting to find the gene signatures of cancer stages based on the omics data. The aim of study was to evaluate and to enrich the array data using gene ontology and ncRNA databases in colorectal cancer.

METHODS

The human colorectal cancer data were obtained from the GEO databank. The downregulated and up-regulated genes were identified after scoring, weighing and merging of the gene data. The clusters with high-score edges were determined from gene networks. The miRNAs related to the gene clusters were identified and enriched. Furthermore, the long non-coding RNA (lncRNA) networks were predicted with a central core for miRNAs.

RESULTS

Based on cluster enrichment, genes related to peptide receptor activity (1.26E-08), LBD domain binding (3.71E-07), rRNA processing (2.61E-34), chemokine (4.58E-19), peptide receptor (1.16E-19) and ECM organization (3.82E-16) were found. Furthermore, the clusters related to the non-coding RNAs, including hsa-miR-27b-5p, hsa-miR-155-5p, hsa-miR-125b-5p, hsa-miR-21-5p, hsa-miR-30e-5p, hsa-miR-588, hsa-miR-29-3p, LINC01234, LINC01029, LINC00917, LINC00668 and CASC11 were found.

CONCLUSION

The comprehensive bioinformatics analyses provided the gene networks related to some non-coding RNAs that might help in understanding the molecular mechanisms in CRC.

Identification of Key Genes Related to Lung Squamous Cell Carcinoma Using Bioinformatics Analysis

Lung squamous cell carcinoma (LUSC) is often diagnosed at the advanced stage with poor prognosis. The mechanisms of its pathogenesis and prognosis require urgent elucidation. This study was performed to screen potential biomarkers related to the occurrence, development and prognosis of LUSC to reveal unknown physiological and pathological processes. Using bioinformatics analysis, the lung squamous cell carcinoma microarray datasets from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases were analyzed to identify differentially expressed genes (DEGs). Furthermore, PPI and WGCNA network analysis were integrated to identify the key genes closely related to the process of LUSC development. In addition, survival analysis was performed to achieve a prognostic model that accomplished good prediction accuracy. Three hundred and thirty–seven up–regulated and 119 down-regulated genes were identified, in which four genes have been found to play vital roles in LUSC development, namely CCNA2, AURKA, AURKB, and FEN1. The prognostic model contained 5 genes, which were all detrimental to prognosis. The AUC of the established prognostic model for predicting the survival of patients at 1, 3, and 5 years was 0.692, 0.722, and 0.651 in the test data, respectively. In conclusion, this study identified several biomarkers of significant interest for additional investigation of the therapies and methods of prognosis of lung squamous cell carcinoma.

MiR-144: A New Possible Therapeutic Target and Diagnostic/Prognostic Tool in Cancers

MicroRNAs (miRNAs) are small and non-coding RNAs that display aberrant expression in the tissue and plasma of cancer patients when tested in comparison to healthy individuals. In past decades, research data proposed that miRNAs could be diagnostic and prognostic biomarkers in cancer patients. It has been confirmed that miRNAs can act either as oncogenes by silencing tumor inhibitors or as tumor suppressors by targeting oncoproteins. MiR-144s are located in the chromosomal region 17q11.2, which is subject to significant damage in many types of cancers. In this review, we assess the involvement of miR-144s in several cancer types by illustrating the possible target genes that are related to each cancer, and we also briefly describe the clinical applications of miR-144s as a diagnostic and prognostic tool in cancers.

MicroRNA in Lung Cancer Metastasis

Tumor metastasis is a hallmark of cancer, with distant metastasis frequently developing in lung cancer, even at initial diagnosis, resulting in poor prognosis and high mortality. However, available biomarkers cannot reliably predict cancer spreading sites. The metastatic cascade involves highly complicated processes including invasion, migration, angiogenesis, and epithelial-to-mesenchymal transition that are tightly controlled by various genetic expression modalities along with interaction between cancer cells and the extracellular matrix. In particular, microRNAs (miRNAs), a group of small non-coding RNAs, can influence the transcriptional and post-transcriptional processes, with dysregulation of miRNA expression contributing to the regulation of cancer metastasis. Nevertheless, although miRNA-targeted therapy is widely studied in vitro and in vivo, this strategy currently affords limited feasibility and a few miRNA-targeted therapies for lung cancer have entered into clinical trials to date. Advances in understanding the molecular mechanism of metastasis will thus provide additional potential targets for lung cancer treatment. This review discusses the current research related to the role of miRNAs in lung cancer invasion and metastasis, with a particular focus on the different metastatic lesions and potential miRNA-targeted treatments for lung cancer with the expectation that further exploration of miRNA-targeted therapy may establish a new spectrum of lung cancer treatments.

MicroRNA-588 regulates invasion, migration and epithelial-mesenchymal transition via targeting EIF5A2 pathway in gastric cancer

Background

miRNAs are potential regulators of genes in many cancers. Here, we confirmed that the expression of miR-588 decreased in gastric cancer (GC) tissues and cells.

Materials and methods

Sixty-seven GC tissues along with noncancerous tissues adjacent to them were included in the study. Quantitative real-time reverse transcription-PCR study was done to quantify the expression levels of mature miRNA. The expression of proteins was determined by Western blot and transwell chamber assay for invasion and migration studies. Immunohistochemical analysis and luciferase assay were done for evaluating the expression of epithelial–mesenchymal transition (EMT) markers and activity of EIF5A2, respectively. In vivo metastatic assay was done by injecting MGC-803 cells into nude mice.

Results

In the 5-year predicted survival study of GC patients included in the study, we found that miR-588 acted as a specific prognostic marker. Overexpression of miR-588 resulted in suppression of cell invasion, migration and progression of EMT, whereas suppression of miR-588 inverted the effects in both in vivo and in vitro experiments. miR-588 retained EIF5A2 by directly binding to the 3′-UTR. EIF5A2 was overexpressed in GC tissue samples, and the expression of miR-588 was inversely correlated to the levels of EIF5A2. The impact of miR-588 on invasion, migration and progression of EMT may be partially due to miR-588–mediated alterations of EiF5A2.

Conclusion

Overall, the findings of the study suggest that miR-588 acts as a tumor suppressor by regulating the invasion, migration and EMT via EIF5A2 pathway, hence presenting miR-588 as a prognostic marker as well as a therapeutic target for GC.

miR-34b-5p inhibition attenuates lung inflammation and apoptosis in an LPS-induced acute lung injury mouse model by targeting progranulin

Inflammation and apoptosis play important roles in the initiation and progression of acute lung injury (ALI). Our previous study has shown that progranulin (PGRN) exerts lung protective effects during LPS-induced ALI. Here, we have investigated the potential roles of PGRN-targeting microRNAs (miRNAs) in regulating inflammation and apoptosis in ALI and have highlighted the important role of PGRN. LPS-induced lung injury and the protective roles of PGRN in ALI were first confirmed. The function of miR-34b-5p in ALI was determined by transfection of a miR-34b-5p mimic or inhibitor in intro and in vivo. The PGRN level gradually increased and subsequently significantly decreased, reaching its lowest value by 24 hr; PGRN was still elevated compared to the control. The change was accompanied by a release of inflammatory mediators and accumulation of inflammatory cells in the lungs. Using bioinformatics analysis and RT-PCR, we demonstrated that, among 12 putative miRNAs, the kinetics of the miR-34b-5p levels were closely associated with PGRN expression in the lung homogenates. The gain- and loss-of-function analysis, dual-luciferase reporter assays, and rescue experiments confirmed that PGRN was the functional target of miR-34b-5p. Intravenous injection of miR-34b-5p antagomir in vivo significantly inhibited miR-34b-5p up-regulation, reduced inflammatory cytokine release, decreased alveolar epithelial cell apoptosis, attenuated lung inflammation, and improved survival by targeting PGRN during ALI. miR-34b-5p knockdown attenuates lung inflammation and apoptosis in an LPS-induced ALI mouse model by targeting PGRN. This study shows that miR-34b-5p and PGRN may be potential targets for ALI treatments.

MicroRNA-588 is downregulated and may have prognostic and functional roles in human breast cancer

Background

We explored the expression pattern, prognostic potential, and functional role of microRNA-588 (miR-588) in human breast cancer (BC).

Material/Methods

The expression pattern of miR-588 was assessed by qPCR in BC cell lines and human BC carcinomas. The correlations between miR-588 and BC patients’ clinicopathological characteristics, as well as BC patients’ overall survival, were statistically assessed. In in vitro culture, MCF-7 and MDA-MB-231 cells were infected with lentivirus to overexpress endogenous miR-588. The subsequent effects of miR-588 upregulation on BC cell proliferation and cisplatin chemosensitivity were examined.

Results

miR-588 was found to be significantly downregulated in both BC cell lines and carcinoma tissues of BC patients. Low expression of miR-588 was closely correlated with BC patients’ poor prognosis of TNM stage, lymph node metastasis, and estrogen receptor status. In addition, patients with low miR-588-expressing carcinomas had much shorter overall survival. In MCF-7 and MDA-MB-231 cells, lentiviral infection induced significant miR-588 upregulation, and miR-588 upregulation had an anti-tumor effect in BC cells by significantly inhibiting cancer proliferation and increasing cisplatin chemosensitivity.

Conclusions

miR-588 is downregulated in BC and its aberrant expression is closely associated with patients’ poor prognosis and overall survival, thus suggesting a biomarker role. miR-588 also has anti-tumor function in BC, making it a potential therapeutic target for BC treatment.