Pathogenesis Of Non-small Cell Lung Cancer Research Articles

<p>Long Non-Coding RNA LINC00491 Contributes to the Malignancy of Non-Small-Cell Lung Cancer via Competitively Binding to microRNA-324-5p and Thereby Increasing Specificity Protein 1 Expression</p>

BackgroundA long non-coding RNA termed as long intergenic non-protein coding RNA 491 (LINC00491) has been validated as an oncogene to promote cancer progression in colon adenocarcinoma. The goal of this study was to determine the expression and carcinogenic functions of LINC00491 in non-small-cell lung cancer (NSCLC). Besides, it was aimed to understand how LINC00491 affects the malignant processes of NSCLC cells.MethodsThe expression of LINC00491 in NSCLC was investigated by bioinformatic analysis and reverse transcription-quantitative PCR. After LINC00491 knockdown, cell counting kit-8 assay, flow cytometry, migration and invasion detection assays as well as nude mice xenograft assay were conducted to test the roles of LINC00491 in NSCLC cells. Two online databases, StarBase 3.0 and miRDB, were utilized to determine the putative target miRNA of LINC00491, and the prediction was subsequently confirmed by luciferase reporter assay, RNA immunoprecipitation assay, reverse transcription-quantitative PCR, Western blotting, and rescue assays.ResultsLINC00491 was overexpressed in both NSCLC tissues and cell lines. Functional investigation revealed that depleted LINC00491 facilitated cell apoptosis and decreased cell proliferation, migration, and invasion in vitro. Additionally, the downregulation of LINC00491 impaired NSCLC cell tumor growth in vivo. Mechanistically, LINC00491 functioned as a competing endogenous RNA by sponging microRNA-324-5p (miR-324-5p) in NSCLC cells. miR-324-5p was weakly expressed in NSCLC and exerted tumor-suppressing actions during cancer progression. Furthermore, specificity protein 1 (SP1) was validated as the direct target of miR-324-5p in NSCLC and was under the regulation of LINC00491 via sponging miR-324-5p. Rescue experiments reconfirmed that miR-324-5p inhibition and SP1 overexpression both abrogated the suppressive roles of LINC00491 deficiency in NSCLC cells.ConclusionLINC00491 promoted the oncogenicity of NSCLC via serving as a miR-324-5p sponge, which further upregulated the expression of SP1. The LINC00491/miR-324-5p/SP1 pathway disclosed a new mechanism of NSCLC pathogenesis and may provide effective targets for better NSCLC treatment.

Long non-coding RNA PRNCR1 modulates non-small cell lung cancer cell proliferation, apoptosis, migration, invasion, and EMT through PRNCR1/miR-126-5p/MTDH axis.

Background: Non-small cell lung cancer (NSCLC) is a highly malignant tumor. Accumulating evidence suggested that prostate cancer non-coding RNA 1 (PRNCR1) participated in the pathogenesis of NSCLC, whereas the elaborate mechanism remains unclear. Hence, the role of PRNCR1 in the progression of NSCLC was investigated.Methods: Levels of PRNCR1, microRNA-126-5p (miR-126-5p), and metadherin (MTDH) were examined by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation was measured using Cell Counting Kit-8 (CCK-8). Flow cytometry was conducted to determine cell apoptosis. Besides, transwell assay was performed to detect cell migration and invasion in NSCLC cells. The expression levels of E-cadherin, N-cadherin, Vimentin, and MTDH were detected via Western blot. Dual-luciferase reporter, RNA immunoprecipitation, and RNA pull down assays were employed to verify the relationship between miR-126-5p and PRNCR1 or MTDH.Results: PRNCR1 and MTDH levels were highly expressed, while miR-126-5p expression was lowly expressed in NSCLC tissues and cell lines. Knockdown of PRNCR1 promoted cell apoptosis, impeded proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) in NSCLC cells, and these effects were abrogated by its target gene of miR-126-5p inhibitor. Moreover, MTDH as the target of PRNCR1, its overexpression reversed the impacts of miR-126-5p mimic on cell behaviors and EMT in vitro. Finally, PRNCR1 and miR-126-5p regulated MTDH expression.Conclusion: PRNCR1 modified cell behaviors and EMT via miR-126-5p/MTDH axis in NSCLC cells, providing a novel thinking for clinical treatment of NSCLC.

Unproductive Effects of ALK Gene Amplification and Copy Number Gain in Non-Small-Cell Lung Cancer. ALK Gene Amplification and Copy Gain in NSCLC.

Background: The Anaplastic Lymphoma Kinase (ALK) gene is known to be affected by several genetic alterations, such as rearrangement, amplification and point mutation. The main goal of this study was to comprehensively analyze ALK amplification (ALK-A) and ALK gene copy number gain (ALK-CNG) in a large cohort of non-small-cell lung cancer (NSCLC) patients in order to evaluate the effects on mRNA and protein expression. Methods: ALK locus number status was evaluated in 578 NSCLC cases by fluorescence in situ hybridization (FISH). In addition, ALK immunohistochemistry and ALK mRNA in situ hybridization were performed. Results: Out of 578 cases, 17 cases showed ALK-A. In addition, 14 cases presented ALK-CNG and 72 cases presented chromosome 2 polyploidy. None of those carrying ALK-A and -CNG showed either ALK immunohistochemical expression or ALK mRNA expression through in situ hybridization. We observed a high frequency of extra copies of the ALK gene. Conclusions: Our findings demonstrated that ALK-A is not involved in mRNA production and consequently is not involved in protein production; these findings support the hypothesis that ALK-A might not play a role in the pathogenesis of NSCLC, underlining the absence of a specific clinical application.

Exome sequencing identifies somatic mutations in novel driver genes in non-small cell lung cancer.

Lung cancer is the leading cause of cancer death worldwide and accounts for more than one-third of all newly diagnosed cancer cases in China. Therefore, it is of great clinical significance to explore new driver gene mutations in non-small-cell lung cancer (NSCLC). Using an initial bioinformatic analysis, we identified somatic gene mutations in 13 patients with NSCLC and confirmed these mutations by targeted sequencing in an extended validation group of 88 patients. Recurrent mutations were detected in UNC5D (7.9%), PREX1 (5.0%), HECW1 (4.0%), DACH1 (2.0%), and GPC5 (2.0%). A functional study was also performed in UNC5D mutants. Mutations in UNC5D promoted tumorigenesis by abolishing the tumor suppressor function of the encoded protein. Additionally, in ten patients with lung squamous cell carcinoma, we identified mutations in KEAP1/NFE2L2 that influenced the expression of target genes in vivo and in vitro. Overall, the results of our study expanded the known spectrum of driver mutations involved in the pathogenesis of NSCLC.

MiR-331-3p Inhibits Tumor Cell Proliferation, Metastasis, Invasion by Targeting MLLT10 in Non-Small Cell Lung Cancer.

ObjectiveMounting research has established the role of microRNAs (miRNAs) as oncogenes or anti-oncogenes (tumor suppressors) in the development and progression of several cancers. The purpose of our current study is to delineate the roles and functional mechanisms of miR-331-3p and MLLT10 in non-small cell lung cancer (NSCLC) tumorigenesis.Patients and MethodsQuantitative reverse transcription-polymerase chain reaction (RT-qPCR) was employed to measure miR-331-3p expression levels in twenty-six matched tumor tissues and non-cancerous tissues collected from patients suffering from NSCLC, and from six NSCLC cell lines separately: A549, H1650, H292, H1299, H1944 and BEAS-2b. We employed the dual-luciferase activity assay to check whether the putative gene, MLLT10, was a downstream target of miR-331-3p in NSCLC pathogenesis and development. Western blot was conducted to analyze the protein expression levels of MLLT10 (AF10), E-cadherin, Vimentin, and GAPDH. CCK-8 assay, transwell migration assay, and transwell invasion assay were carried out to observe the functions of miR-331-3p and MLLT10 on NSCLC tumor cell proliferation, metastasis, and invasion, respectively. To identify whether the metastasis of NSCLC tumor cells was EMT-mediated, supplementary experiments involving E-cadherin and Vimentin were implemented.ResultsmiR-331-3p was downregulated in NSCLC, which promoted tumor cell proliferation, whereas the overexpression of miR-331-3p inhibited tumor cell proliferation. Being a direct target of miR-331-3p, MLLT10 was negatively modulated by miR-331-3p, which suppressed tumor cell proliferation, migration, and invasion in NSCLC. However, MLLT10 overexpression alleviated the above inhibitory effects. Furthermore, EMT-mediated metastasis was proved to be present in NSCLC.ConclusionmiR-331-3p played a suppressor role in NSCLC tumor cell proliferation, EMT-mediated metastasis, and invasion by targeting MLLT10. Our findings highlighted that miR-331-3p/MLLT10 axis could be useful as a clinical diagnostic marker and therapeutic target in NSCLC patients.

Circular RNA circ_0000284 plays an oncogenic role in the progression of non-small cell lung cancer through the miR-377-3p-mediated PD-L1 promotion

BackgroundCircular RNAs (circRNAs), a subgroup of non-coding RNAs, are recognized as pivotal mediators in various types of cancers. CircRNA_0000284 (circ_0000284) was manifested to participate in the development of non-small cell lung cancer (NSCLC). The novel functional mechanism of circ_0000284 in NSCLC was investigated in our current study.MethodsWe exploited quantitative real-time polymerase chain reaction (qRT-PCR) to analyze the relative RNA (circRNA, miRNA and mRNA) expression. The assessment of cell proliferation and colony formation was executed by Cell Counting Kit-8 (CCK-8) and colony formation assay, respectively. Transwell assay was implemented to examine cell migration and invasion. All protein levels were assayed using western blot. The role of circ_0000284 in vivo was evaluated via xenograft model. The target relation was estimated by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays.ResultsAs for the biological characterization, circ_0000284 was highly stable and localized in the cytoplasm. Circ_0000284 was up-regulated in NSCLC and could predict poor prognosis of NSCLC patients. Both in vitro and in vivo, down-regulation of circ_0000284 refrained tumorigenesis of NSCLC. Besides, microRNA-377-3p (miR-377-3p) was a miRNA target of circ_0000284, and targeted programmed death-ligand 1 (PD-L1). Circ_0000284 was a cancer-promoting circRNA in NSCLC via regulating the miR-377-3p/PD-L1 axis.ConclusionThus, our results unraveled that circ_0000284 facilitated the progression of NSCLC by up-regulating the PD-L1 expression as a competing endogenous RNA (ceRNA) of miR-377, possibly developing a different perspective in understanding the molecular pathogenesis of NSCLC.

Knockdown of lncRNA XIST Suppresses Cell Tumorigenicity in Human Non-Small Cell Lung Cancer by Regulating miR-142-5p/PAX6 Axis.

BackgroundLong noncoding RNA X inactivate-specific transcript (lncRNA XIST) has been identified to contribute to the development and progression of non-small cell lung cancer (NSCLC). Thus, it is important to explore more specific functions and molecular mechanisms of XIST in NSCLC tumorigenesis.Materials and MethodsThe expression of XIST, microRNA (miR)-142-5p and paired box 6 (PAX6) was measured using quantitative real-time polymerase chain reaction or Western blot, respectively. Cell proliferation was analyzed using cell counting kit-8 (CCK-8) assay. Flow cytometry was utilized to measure apoptotic cells. Cell migration and invasion were determined by Transwell assay. The interaction between miR-142-5p and XIST or PAX6 was confirmed by the dual-luciferase reporter assay and RNA immunoprecipitation assay. In vivo experiments were performed through the murine xenograft model.ResultsXIST was elevated in NSCLC, and XIST knockdown suppressed cell proliferation, migration, invasion and induced apoptosis in vitro as well as repressed tumor growth in vivo. MiR-142-5p was a target of XIST, and silencing miR-142-5p reversed the anti-tumor functions mediated by XIST knockdown in NSCLC cells. PAX6 was confirmed to be a target of miR-142-5p, and the inhibitory effects caused by miR-142-5p restoration in NSCLC cell malignant phenotypes were attenuated by PAX6 overexpression. Besides that, XIST could indirectly regulate PAX6 expression by sponging miR-142-5p in vivo and in vitro.ConclusionXIST suppresses cell tumorigenicity in human NSCLC by regulating miR-142-5p/PAX6 axis, which indicates a novel insight into the pathogenesis of NSCLC and lays a foundation for the molecular therapy of NSCLC.

Microarray data analysis on gene and miRNA expression to identify biomarkers in non-small cell lung cancer

BackgroundThe aim of this study was to gain further investigation of non-small cell lung cancer (NSCLC) tumorigenesis and identify biomarkers for clinical management of patients through comprehensive bioinformatics analysis.MethodsmiRNA and mRNA microarray datasets were downloaded from GEO (Gene Expression Omnibus) database under the accession number GSE102286 and GSE101929, respectively. Genes and miRNAs with differential expression were identified in NSCLC samples compared with controls, respectively. The interaction between differentially expressed genes (DEGs) and differentially expressed miRNAs (DEmiRs) was predicted, followed by functional enrichment analysis, and construction of miRNA-gene regulatory network, protein-protein interaction (PPI) network, and competing endogenous RNA (ceRNA) network. Through comprehensive bioinformatics analysis, we anticipate to find novel therapeutic targets and biomarkers for NSCLC.ResultsA total of 123 DEmiRs (5 up- and 118 down-regulated miRNAs) and 924 DEGs (309 up- and 615 down-regulated genes) were identified. These genes and miRNAs were significantly involved in different pathways including adherens junction, relaxin signaling pathway, and axon guidance. Furthermore, hsa-miR-9-5p, has-miR-196a-5p and hsa-miR-31-5p, as well as hsa-miR-1, hsa-miR-218-5p and hsa-miR-135a-5p were shown to have higher degree in the miRNA-gene regulatory network and ceRNA network, respectively. Furthermore, BIRC5 and FGF2, as well as RTKN2 and SLIT3 were hubs in the PPI network and ceRNA network, respectively.ConclusionSeveral pathways (adherens junction, relaxin signaling pathway, and axon guidance) miRNAs (hsa-miR-9-5p, has-miR-196a-5p, hsa-miR-31-5p, hsa-miR-1, hsa-miR-218-5p and hsa-miR-135a-5p) and genes (BIRC5, FGF2, RTKN2 and SLIT3) may play important roles in the pathogenesis of NSCLC.

DNMT1 promotes cell proliferation via methylating hMLH1 and hMSH2 promoters in EGFR-mutated non-small cell lung cancer.

Aberrant DNA methylation is a common form of epigenetic alterations and it has been proved to be closely related to many cancers, while its role in epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) is not clear. This study focuses on the role of DNA methyltransferase 1 (DNMT1) in EGFR-mutated NSCLC pathogenesis. First, the expression of DNMT1 was up-regulated, while the expressions of human mutL homolog 1(hMLH1) and human mutS homolog 2 (hMSH2) were down-regulated in EGFR-mutated NSCLC patients and cell line HCC827. The results of the correlation analysis showed that DNMT1 expression was inversely correlated with the expressions of hMLH1 and hMSH2. Then, we found that DNMT1 enhanced the promoter methylation levels of hMLH1 and hMSH2, thus suppressing their expressions. DNMT1 knockdown inhibited the proliferation of HCC827 cells, while both hMLH1 knockdown and hMSH2 knockdown could eliminate its inhibitory effect on cell proliferation. In xenograft mouse models, lentiviral vector-sh-DNMT1 could significantly reduce tumor volumes, confirmed that DNMT1 inhibited tumor cell proliferation in vivo. In conclusion, DNMT1 suppressed the expressions of hMLH1 and hMSH2 via elevating their promoter methylation, thus promoting cell proliferation in EGFR-mutated NSCLC.

Role of LINC00152 in non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) accounts for about 85% of all lung cancer cases. The pathogenesis of NSCLC involves complex gene networks that include different types of non-coding RNAs, such as long non-coding RNAs (lncRNAs). The role of lncRNAs in NSCLC is gaining an increasing interest as their function is being explored in various human cancers. Recently, a new oncogenic lncRNA, LINC00152 (cytoskeleton regulator RNA (CYTOR)), has been identified in different tumor types. In NSCLC, the high expression of LINC00152 in tumor tissue and peripheral blood samples has been shown to be associated with worse prognoses of NSCLC patients. Overexpression of LINC00152 has been confirmed to promote the proliferation, invasion, and migration of NSCLC cells in vitro, as well as increase tumor growth in vivo. This review discusses the role of LINC00152 in NSCLC.

LncRNA DSCAM-AS1 promotes non-small cell lung cancer progression via regulating miR-577/HMGB1 axis.

Non-small cell lung cancer (NSCLC) is a major source of cancer mortality. Long non-coding RNA DSCAM-AS1 has been certified to be involved in the pathogenesis of NSCLC. This study aimed to further investigate the potential mechanism of DSCAM-AS1 in NSCLC progression. The expressions of DSCAM-AS1, miR-577, and high mobility group box 1 (HMGB1) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot assay. Cell viability was assessed by Cell Counting Kit-8 (CCK-8) assay. Flow cytometry assay was conducted to monitor cell apoptosis. Cell migration and invasion were measured by transwell assay. Wnt/β-catenin pathway-related factors were detected by western blot assay. The relationship between DSCAM-AS1, miR-577, and HMGB1 was validated by bioinformatics analysis and dual-luciferase reporter assay. The xenograft mouse model was established to analyze tumor growth in vivo. DSCAM-AS1 and HMGB1 were upregulated, while miR-577 was downregulated in NSCLC tissues and cells. DSCAM-AS1 promoted cell proliferation, migration and invasion, and restrained cell apoptosis in NSCLC cells. Overexpression of HMGB1 reversed the effects of DSCAM-AS1 depletion on the progression of NSCLC. DSCAM-AS1 modulated HMGB1 expression by sponging miR-577. DSCAM-AS1 regulated the Wnt/β-catenin pathway by regulating miR-577 and HMGB1. DSCAM-AS1 knockdown blocked the tumor growth in vivo. In conclusion, DSCAM-AS1 facilitated NSCLC progression by regulating the HMGB1-mediated Wnt/β-catenin pathway, providing a promising therapeutic target for NSCLC.

The genomic landscape of nonsmall cell lung carcinoma in never smokers.

Lung cancer is the number one cause of cancer-related death worldwide with cigarette smoking as its major risk factor. Although the incidence of lung cancer in never smokers is rising, this subgroup of patients is underrepresented in genomic studies of lung cancer. Here, we assembled a prospective cohort of 46 never-smoking, nonsmall cell lung cancer (NSCLC) patients and performed whole-exome and low-coverage whole-genome sequencing on tumors and matched germline DNA. We observed fewer somatic mutations, genomic breakpoints and a smaller fraction of the genome with chromosomal instability in lung tumors from never smokers compared to smokers. The lower number of mutations, enabled us to identify TSC22D1 as a potential driver gene in NSCLC. On the other hand, the frequency of mutations in actionable genes such as EGFR and ERBB2 and of amplifications in MET were higher, while the mutation rate of TP53, which is a negative prognostic factor, was lower in never smokers compared to smokers. Together, these observations suggest a more favorable prognosis for never smokers with NSCLC. Classification of somatic mutations into six-substitution type patterns or into 96-substitution type signatures revealed distinct clusters between smokers and never smokers. Particularly, we identified in never smokers signatures related to aging, homologous recombination damage and APOBEC/AID activity as the most important underlying processes of NSCLC. This further indicates that second-hand smoking is not driving NSCLC pathogenesis in never smokers.

BATF acts as an oncogene in non-small cell lung cancer.

One of the main causes of cancer incidence and mortality worldwide is lung cancer. This study focused on the function of basic leucine zipper ATF-like transcription factor (BATF) in non-small cell lung cancer (NSCLC). Using NSCLC patient data from The Cancer Genome Atlas, the present study demonstrated that BATF expression in NSCLC tissues was significantly higher compared with that in adjacent non-tumor tissues (P=6.56×10−6). Lentivirus-mediated short hairpin RNA (shRNA) was used to knock down BATF expression in the human A549 NSCLC cell line and assessed by reverse transcription-quantitative PCR and western blotting. Cell proliferation was evaluated by MTT assay and Celigo imaging cytometry. Apoptosis was detected by fluorescence-activated cell sorting and caspase 3/7 activity analysis. The results revealed that knockdown of BATF inhibited the proliferation of A549 cells. Compared with that of the control group, the apoptosis rate of the BATF-shRNA group was significantly higher. In summary, knockdown of BATF inhibited the proliferation of A549 cells and promoted apoptosis. These results provide important information about the underlying mechanism of the pathogenesis of NSCLC.

Identification of key microRNAs and hub genes in non-small-cell lung cancer using integrative bioinformatics and functional analyses.

Non-small-cell lung cancer (NSCLC) is an extremely debilitating respiratory malignancy. However, the pathogenesis of NSCLC has not been fully clarified. The main objective of our study was to identify potential microRNAs (miRNAs) and their regulatory mechanism in NSCLC. Using a systematic review, two NSCLC-associated miRNA data sets (GSE102286 and GSE56036) were obtained from Gene Expression Omnibus, and the differentially expressed miRNAs (DE-miRNAs) were accessed by GEO2R. Survival analysis of candidate DE-miRNAs was conducted using the Kaplan-Meier plotter database. To further illustrate the roles of DE-miRNAs in NSCLC, their potential target genes were predicted by miRNet and were annotated by the Database for Annotation, Visualization and Integrated Discovery (DAVID) program. Moreover, the protein-protein interaction (PPI) and miRNA-hub gene regulatory network were established using the STRING database and Cytoscape software. The function of DE-miRNAs in NSCLC cells was evaluated by transwell assay. Compared with normal tissues, a total of eight DE-miRNAs was commonly changed in two data sets. The survival analysis showed that six miRNAs (miR-21-5p, miR-31-5p, miR-708-5p, miR-30a-5p, miR-451a, and miR-126-3p) were significantly correlated with overall survival. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that target genes of upregulated miRNAs were enriched in pathways in cancer, microRNAs in cancer and proteoglycans in cancer, while the target genes of downregulated miRNAs were mainly associated with pathways in cancer, the PI3K-Akt signaling pathway and HTLV-I infection. Based on the miRNA-hub gene network and expression analysis, PTEN, EGFR, STAT3, RHOA, VEGFA, TP53, CTNNB1, and KRAS were identified as potential target genes. Furthermore, all six miRNAs exhibited significant effects on NSCLC cell invasion. These findings indicate that six DE-miRNAs and their target genes may play important roles in the pathogenesis of NSCLC, which will provide novel information for NSCLC treatments.

Downregulation Of microRNA-133b And Its Clinical Value In Non-Small Cell Lung Cancer.

BackgroundPrevious studies have investigated the expression of miR-133b in non-small cell lung cancer (NSCLC); however, its underlying mechanism in relation to the pathogenesis of NSCLC remains unclear.MethodsThe aim of this study was to investigate the correlation between miR-133b expression and clinical parameters based on the Cancer Genome Atlas (TCGA) and real-time quantitative real-time PCR (RT-qPCR) data. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to identify the biological function of miR-133b. A protein-protein interaction (PPI) network was constructed to screen for hub genes. The Gene Expression Profiling Interaction Analysis (GEPIA) and the Human Protein Atlas databases (HPAD) were employed to validate the hub genes. The cBioPortal database was used to identify neighboring genes with alteration frequencies greater than 20% gene alterations.ResultsmiR-133b was downregulated in NSCLC tissues, and expression was correlated with lymph node metastasis (P < 0.05). A total of 362 genes were considered as the potential targets of miR-133b in NSCLC. These candidate target genes highly enriched in various key pathways such as the PI3K-Akt pathways, P53 signal pathways, and ECM-receptor interaction. PPI revealed 10 genes as hub genes with node degrees ≥10.ConclusionThe study validated that miR-133b is downregulated in NSCLC. In addition, miR-133b might function as a biomarker for the diagnosis and prognosis of NSCLC. Bioinformatics analysis revealed that miR-133b could be involved in NSCLC metastasis.

YTHDF1 links hypoxia adaptation and non-small cell lung cancer progression

Hypoxia occurs naturally at high-altitudes and pathologically in hypoxic solid tumors. Here, we report that genes involved in various human cancers evolved rapidly in Tibetans and six Tibetan domestic mammals compared to reciprocal lowlanders. Furthermore, m6A modified mRNA binding protein YTHDF1, one of evolutionary positively selected genes for high-altitude adaptation is amplified in various cancers, including non-small cell lung cancer (NSCLC). We show that YTHDF1 deficiency inhibits NSCLC cell proliferation and xenograft tumor formation through regulating the translational efficiency of CDK2, CDK4, and cyclin D1, and that YTHDF1 depletion restrains de novo lung adenocarcinomas (ADC) progression. However, we observe that YTHDF1 high expression correlates with better clinical outcome, with its depletion rendering cancerous cells resistant to cisplatin (DDP) treatment. Mechanistic studies identified the Keap1-Nrf2-AKR1C1 axis as the downstream mediator of YTHDF1. Together, these findings highlight the critical role of YTHDF1 in both hypoxia adaptation and pathogenesis of NSCLC.

Construction of a competing endogenous RNA network using differentially expressed lncRNAs, miRNAs and mRNAs in non‑small cell lung cancer.

The competing endogenous RNA (ceRNA) network is crucial for the development and progression of tumors, including non-small cell lung cancer (NSCLC). However, what type of ceRNA network regulates NSCLC has not been clarified. The present study aimed to elucidate the long non-coding RNA (lncRNA)/microRNA (miRNA)/mRNA ceRNA network in NSCLC, particularly for the significance of lncRNAs in NSCLC. NSCLC-specific differentially expressed lncRNAs, miRNAs and mRNAs in the Cancer Genome Atlas (TCGA) were analyzed and their relationship was analyzed by a ceRNA network. Their potential functions of differentially expressed mRNAs were analyzed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Furthermore, the expression levels of four selected lncRNAs in TCGA were determined and their associated survival of patients was examined. In addition, the expression profiles of these four lncRNAs in 48 NSCLC specimens and cell lines, their cellular distribution and associated clinical parameters were examined. We successfully constructed a ceRNA network, including 113 lncRNAs, 12 miRNAs and 36 mRNAs differentially expressed between NSCLC and non-tumor tissues. LINC00525, MED4-AS1, STEAP2-AS1 and SYNPR-AS1 lncRNAs were selected and validated for their association with the survival of NSCLC patients. The expression of these lncRNAs was upregulated in 48 NSCLC tissues and was varying in NSCLC cells. While LINC00525 was mainly expressed in the cytoplasm, MED4-AS1 was in both the nucleus and cytoplasm of A549 cells. In addition, the expression of LINC00525 was significantly associated with smoking history (P<0.05); MED4-AS1 was significantly associated with women, poor differentiation and lymph node metastasis (P<0.05); STEAP2-AS1 was significantly associated with women (P<0.01); and SYNPR-AS1 was significantly associated with women and adenocarcinoma (P<0.05). These lncRNAs may be valuable biomarkers for prognosis of NSCLC and the ceRNA network may provide new insights in the pathogenesis of NSCLC.

Long Non-Coding RNAs (lncRNAs) Tumor-Suppressive Role of lncRNA on Chromosome 8p12 (TSLNC8) Inhibits Tumor Metastasis and Promotes Apoptosis by Regulating Interleukin 6 (IL-6)/Signal Transducer and Activator of Transcription 3 (STAT3)/Hypoxia-Inducible Factor 1-alpha (HIF-1α) Signaling Pathway in Non-Small Cell Lung Cancer.

BackgroundLong non-coding RNAs (lncRNAs) exert various functions in human cancers. However, the biological functions of lncRNAs in non-small cell lung cancer (NSCLC) are unknown. In the present study we investigated the tumor-suppressive role of lncRNA on chromosome 8p12 (TSLNC8) in the pathogenesis and progression of NSCLC.Material/MethodsqRT-PCR was carried out to evaluate the expression of TSLNC8 in lung cancer cell lines. The effects of TSLNC8 on A549 cells proliferation, migration, and invasion were analyzed using CCK-8 assay, wound healing assay, Transwell assay, and Western blot analysis. We used flow cytometry to assess cell apoptosis, and cell autophagy was assessed by Western blot analysis and immunofluorescence staining. Levels of proteins in the IL-6/STAT3/HIF-1α pathway were measured by Western blot analysis.ResultsThe results revealed that TSLNC8 was significantly downregulated in lung cancer cells compared to normal bronchial epithelial cells. Further experiments showed that overexpression of TSLNC8 in A549 cells significantly inhibited proliferation in a time-dependent manner and promoted cell apoptosis. We found that TSLNC8 overexpression suppressed cell migration and invasion, and upregulation of TSLNC8 regulated the protein levels of Beclin-1, p62, ATG14, and LC3-II and inhibited the IL-6/STAT3/HIF-1α signaling pathway.ConclusionslncRNA TSLNC8 remarkably inhibited the proliferation and migration and accelerated apoptosis of lung cancer cells by targeting the IL-6/STAT3/HIF-1α signaling pathway. TSLNC8 may be a potential therapeutic target for the diagnosis and treatment of NSCLC.

Circular RNA HIPK3 induces cell proliferation and inhibits apoptosis in non-small cell lung cancer through sponging miR-149

ABSTRACTCircular RNAs (circRNAs) are a class of endogenous noncoding RNAs that are demonstrated to be potent regulators in the development of various types of human cancers, including non-small cell lung cancer (NSCLC). In the present study, the level of circRNA-HIPK3 were measured by Taq-man based quantitative real-time PCR (qRT-PCR) analysis in both NSCLC patient specimens and cells, which showed that circRNA-HIPK3 was upregulated in both NSCLC tissues and cell lines. Cell counting kit-8 (CCK-8), migration and flow-cytometry assays indicated that circRNA-HIPK3 participated in the regulation of the proliferation, migration, invasion and apoptosis of NSCLC cells. MiR-193a expression was increased by circHIPK3 silencing. We then showed that miR-149 interacts with FOXM1 by binding to the 3ʹ-untranslated region (UTR). Further, ectopic overexpression of miR-149 by transfecting miR-149 mimics significantly inhibited growth, migration and invasion of HSCLCs, which was found to be mediated through FOXM1. Moreover, miR-149 overexpression decreases the viability and proliferation of HSCLCs. Therefore, our data suggest that circHIPK3 regulates the function of NSCLCs through miR-149-mediated FOXM1 expression regulation, potentially providing a novel insight into the pathogenesis of NSCLC.

MiR-650 promotes non-small cell lung cancer cell proliferation and invasion by targeting ING4 through Wnt-1/β-catenin pathway.

Non-small cell lung cancer (NSCLC) is the most frequent cancer worldwide with a poor 5-year survival. miR-650 acts as an oncogene and regulates tumor progress in various cancers. Molecular mechanisms of miR-650 in NSCLC cell proliferation and invasion was studied. The mRNA levels of miR-650 and special genes were calculated using RT-qPCR. MTT and transwell assays were applied to measure the proliferative and invasive ability. Kaplan-Meier method was used to assess the survival of NSCLC patients. miR-650 was upregulated in NSCLC and upregulation of miR-650 was associated with a poor overall survival of NSCLC, while the results of ING4 demonstrated the opposite results. miR-650 promoted proliferation and invasion through Wnt-1/β-catenin pathway by targeting inhibitor of growth 4 (ING4) in A549 cells. ING4 was a direct target gene of miR-650 and the expression of ING4 was mediated by exogenous altering the expression of miR-650. Remarkably, alterations of ING4 expression eliminated the functions of miR-650 on the proliferation and metastasis of NSCLC. miR-650 enhanced A549 cell proliferation and invasion through Wnt-1/β-catenin pathway by directly targeting the 3′-UTR of ING4 mRNA. The newly identified miR-650/ING4 axis provides a novel insight into the pathogenesis of NSCLC.