Knockdown of Long Noncoding RNA ENST457720 Inhibits Proliferation of Non-Small Cell Lung Cancer Cells In Vitro and In Vivo

MAPKAPK5-AS1/miR-515-5p/CAB39 Axis Contributes to Non-small Cell Lung Cancer Cell Proliferation and Migration

Several studies have elucidated the pivotal function that long noncoding RNAs (lncRNAs) exerted on the initiation and development of various human carcinomas, encompassing non-small cell lung cancer (NSCLC). In spite of the fact that lncRNA MAPKAPK5 antisense RNA 1 (MAPKAPK5-AS1) has already been investigated by researchers and confirmed to play oncogenic roles in colorectal cancer, the underlying regulatory function of MAPKAPK5-AS1 in NSCLC cells still remain unclear. In our research, we found that MAPKAPK5-AS1 was expressed at high levels in NSCLC cells. Biological functional assays unclosed that downregulation of MAPKAPK5-AS1 repressed proliferative and migratory capacities whereas promoted apoptotic level in NSCLC cells. Molecular mechanism experiments confirmed that, in NSCLC cells, MAPKAPK5-AS1 combined with miR-515-5p and negatively modulated miR-515-5p expression level. Besides, calcium-binding protein 39 (CAB39) expression level was verified to be negatively modulated by miR-515-5p whereas positively modulated by MAPKAPK5-AS1 in NSCLC cells. Furthermore, rescued-function assays disclosed that inhibited miR-515-5p expression or overexpressed CAB39 could restore the suppressive influence of MAPKAPK5-AS1 silence on NSCLC progression. In summary, MAPKAPK5-AS1 upregulates CAB39 expression level to facilitate NSCLC progression by sequestering miR-515-5p, providing promising biomarkers for NSCLC treatment.

Long Non-Coding RNA CRYBG3 Promotes Lung Cancer Metastasis via Activating the eEF1A1/MDM2/MTBP Axis

The occurrence of distant tumor metastases is a major barrier in non-small cell lung cancer (NSCLC) therapy, and seriously affects clinical treatment and patient prognosis. Recently, long non-coding RNAs (lncRNAs) have been demonstrated to be crucial regulators of metastasis in lung cancer. The aim of this study was to reveal the underlying mechanisms of a novel lncRNA LNC CRYBG3 in regulating NSCLC metastasis. Experimental results showed that LNC CRYBG3 was upregulated in NSCLC cells compared with normal tissue cells, and its level was involved in these cells' metastatic ability. Exogenously overexpressed LNC CRYBG3 increased the metastatic ability and the protein expression level of the metastasis-associated proteins Snail and Vimentin in low metastatic lung cancer HCC827 cell line. In addition, LNC CRYBG3 contributed to HCC827 cell metastasis in vivo. Mechanistically, LNC CRYBG3 could directly combine with eEF1A1 and promote it to move into the nucleus to enhance the transcription of MDM2. Overexpressed MDM2 combined with MDM2 binding protein (MTBP) to reduce the binding of MTBP with ACTN4 and consequently increased cell migration mediated by ACTN4. In conclusion, the LNC CRYBG3/eEF1A1/MDM2/MTBP axis is a novel signaling pathway regulating tumor metastasis and may be a potential therapeutic target for NSCLC treatment.

LINC01152 upregulates MAML2 expression to modulate the progression of glioblastoma multiforme via Notch signaling pathway

Glioblastoma multiforme (GBM) brings serious physical and psychological pain to GBM patients, whose survival rate remains not optimistic. Long noncoding RNAs (lncRNAs) have been reported to participate in the progression of many cancers, including GBM. However, the mechanism and function of long intergenic non-protein coding RNA 1152 (LINC01152) in GBM are still unclear. In our study, we aimed to explore the function and mechanism of LINC01152 in GBM. Then qRT-PCR analysis was implemented to search the expression of RNAs in GBM tissues and cells. Functional assays such as EdU assay, colony formation assay, TUNEL assay and flow cytometry analysis were conducted to estimate GBM cell proliferation and apoptosis. RNA pull down assay, luciferase reporter assay, RIP and ChIP assays were implemented to search the binding between molecules. As a result, we discovered that LINC01152 was upregulated in GBM tissues and cells. LINC01152 and mastermind like transcriptional coactivator 2 (MAML2) could both play the oncogenic part in GBM. Moreover, LINC01152 positively regulated MAML2 in GBM by sponging miR-466 and recruiting SRSF1. In turn, RBPJ/MAML2 transcription complex was found to activate the transcription of LINC01152 in GBM cells. In conclusion, LINC01152 could upregulate the expression of MAML2 to promote tumorigenesis in GBM via Notch signaling pathway.

Differential expression of long noncoding RNAs from dental pulp stem cells in the microenvironment of the angiogenesis

INTRODUCTION

Angiogenesis is important in pulp-dentin formation. Among the regulatory factors, long noncoding RNA (LncRNA) is a class of functional RNA molecules that are not translated into protein and involved in regulating multiple physiological processes. The different expression of LncRNA and its target gene in dental pulp stem cells (DPSCs) were explored and may provide a theoretical basis for future regulation of dental pulp angiogenesis.

METHODS

In this study, we cultured DPSCs from healthy dental pulp tissues and divided them into two groups: the normal DPSCs and the DPSCs cultured in vascular induction medium. In total, 40,173 LncRNA probes and 20,730 protein coding mRNAs were detected through microarray, which were then verified by the quantitative reverse transcription-polymerase chain reaction (qRT-PCR) method.

RESULTS

The result of differential expressions measured in LncRNA through microarray showed that 376 LncRNAs increased significantly and 426 were downregulated among the two groups of cells. Moreover, the mRNA microarray in normal cultured DPSCs showed that 629 LncRNAs were significantly upregulated, while 529 of them were downregulated compared with the DPSCs that were cultured in vascular induction medium. Gene ontology (GO) analysis inferred the molecular function of mRNAs. Pathway analysis showed that 52 signaling pathways were involved in the differentiation process of DPSCs. qRT-PCR analysis, conducted for validation, showed results consistent with the microarray analysis.

CONCLUSIONS

We found that a number of different regulators are involved in inducing vascular differentiation of DPSCs, which provides a foundation for subsequent experiments.

Silencing of LINC00461 enhances radiosensitivity of lung adenocarcinoma cells by down-regulating HOXA10 via microRNA-195

Lung adenocarcinoma is recognized as one of the most recurrent tumours in adults. Long non‐coding RNAs (lncRNAs) are non–protein‐coding transcripts and have been demonstrated to regulate biological functions during tumorigenesis. Our study aims to investigate the underlying molecular mechanisms of LINC00461/microRNA‐195 (miR‐195)/HOXA10 responsible for its involvement in lung adenocarcinoma. We firstly selected differentially expressed lncRNAs and genes by the Cancer Genome Atlas (TCGA) database and Gene Expression Omnibus (GEO). The functional role of LINC00461 in lung adenocarcinoma was then determined using ectopic expression, knockdown and reporter assay experiments. Besides, we detected the expression profiles of LINC00461, miR‐195, HOXA10 and apoptosis‐ and invasion‐related genes. Cell proliferation, migration and invasion were evaluated. In vivo tumour formation ability was analysed. Overexpressed LINC00461 and HOXA10 but down‐regulated miR‐195 were observed in primary and metastatic lung adenocarcinoma. LINC00461 negatively regulated miR‐195, while miR‐195 negatively regulated HOXA10. Forced LINC00461 expression decreased expression of miR‐195 and Bax, increased expression of HOXA10, MMP‐2, MMP‐9 and Bcl‐2, promoted cell proliferation, migration and invasion as well as tumour formation, and enhanced radiosensitivity of lung adenocarcinoma cells. However, these effects were reversed by lentivirus‐mediated miR‐195–forced expression, thereby suggesting that miR‐195 could antagonize the harmful effect of LINC00461 on lung adenocarcinoma cells. Collectively, the present study provides evidence supporting the inhibitory effect of LINC00461 silencing on lung adenocarcinoma, which suppresses lung adenocarcinoma cell migration, invasion and radiosensitivity via HOXA10 by binding to miR‐195, which provides a promising basis for the targeted intervention treatment for human lung adenocarcinoma.

LncRNA-ENST00000501520 promotes the proliferation of malignant-transformed BEAS-2B cells induced with coal tar pitch mediated by target genes

As a human carcinogen, coal tar pitch (CTP) can significantly increase the risk of lung cancer. However, the mechanism underlying CTP-induced lung carcinogenesis has not been well understood. This study aims to explore the role of the LncRNA-ENST00000501520 in the proliferation of malignant-transformed human bronchial epithelial cells (BAES-2B) induced by CTP extract for the first time. BEAS-2B cells were stimulated with 2.4 μg/mL CTP extract, and then passaged for three times, which were named passage 1 and then passaged until passage 30 (named as CTP group). The ENST000001520 of cells in CTP group was interfered using siRNA. The results showed that ENST000001520 located in cell nucleus (>80%) had no or weak ability of protein encoding. After interference of ENST000001520, the migration and proliferation of cells in CTP group were inhibited, and the cell cycle was arrested in the G0/G1 phase; however, the apoptosis of cells in CTP group was promoted. The target genes (SKB1, CLTB, TAP2, PIPK2, and SOCS3) of ENST000001520 were screened out, and the mRNA and protein expression of SBK1 and SOCS3 was significantly decreased after ENST000001520 interference. SBK1 and SOCS3 may play a promoting role in occurrence and development of cancers. The study suggests that LncRNA-ENST00000501520 could promote the proliferation in malignant-transformed BEAS-2B cells induced with CTP extract which may be mediated by target genes. This study may provide a new target for prevention and treatment of lung cancer.

Long non‑coding RNA FER1L4 inhibits cell proliferation and metastasis through regulation of the PI3K/AKT signaling pathway in lung cancer cells

Lung cancer is among the most common malignancies worldwide; however, the current understanding of its detailed mechanism remains limited. Long non-coding RNAs (lncRNAs) were previously identified to serve significant roles in tumorigenesis. The present study aimed to investigate the role of a novel lncRNA, Fer-1-like family member 4 (FER1L4), in lung tumorigenesis. In the present study, it was demonstrated that the expression level of FER1L4 was significantly decreased in clinical lung cancer tissues and in cultured lung cancer cells, as evidenced by reverse transcription-quantitative polymerase chain reaction analysis. Overexpression of FER1L4 in lung cancer cell lines A549 and 95D inhibited colony formation, cell proliferation and cell migration capacity, measured by colony formation assays, cell proliferation assays and Transwell assays, respectively. Overexpression of FER1L4 led to a reduction in the expression levels of phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) in A549 and 95D cells, whereas, activation of PI3K/Akt signaling using a small molecular inhibitor of phosphatase and tensin homolog, reversed the inhibitory effects of FER1L4 on cell proliferation and metastasis. All of these results suggested that the lncRNA FER1L4 suppressed cell proliferation and metastasis by inhibiting the PI3K/Akt signaling pathway in lung cancer.

Long non-coding RNA BX357664 inhibits cell proliferation and metastasis in human lung cancer

Long non-coding RNAs (lncRNAs) have been investigated in human carcinogenesis. The lncRNA BX357664 has emerged as a novel lncRNA that was initially recognized by a microarray analysis. The present study aimed to identify the expression and functional roles of lncRNA BX357664 in lung cancer. The transcription level of BX357664 was initially revealed to be downregulated in clinical lung cancer tissues and in a series of lung cancer cell lines. Clinical data demonstrated that the high expression of BX357664 was associated with tumor size, distant metastasis and Tumor-Node-Metastasis stage. Following the overexpression of BX357664 in A549 and 95D cells, the potential of cells to form colonies, as well as the proliferation and motility abilities, were revealed to be decreased. Furthermore, the cell cycle was arrested in the G0/G1 phase by BX357664 modulation. Transwell analysis and a wound-healing assay also demonstrated that overexpression of BX357664 in A549 and 95D cells significantly inhibited cell migration and invasion. These data suggested that BX357664 inhibits cell proliferation and metastasis in lung cancer. The results of the present study provided evidence that BX357664 is a novel lncRNA that may aid in the diagnosis and treatment of lung cancer.

Long noncoding RNA homeobox A11 antisense promotes transforming growth factor β1‑induced fibrogenesis in cardiac fibroblasts

Cardiac fibrosis is closely associated with various heart diseases and is an important pathological feature of cardiac remodeling. However, detailed mechanisms underlying cardiac fibrosis remain largely unknown. Long noncoding RNAs (lncRNAs) are reported to serve significant roles in the development of cardiac fibrosis. The present study aimed to identify the role of a novel lncRNA, homeobox A11 antisense (HOXA11‑AS), in cardiac fibrosis. Overexpression of HOXA11‑AS in mouse cardiac fibroblasts (CFs) increased the expression of transforming growth factor β1 (TGFβ1) and its downstream molecules, while knockdown of HOXA11‑AS inhibited the TGFβ1 signaling pathway. Furthermore, as determined by colony formation and MTT assays, HOXA11‑AS overexpression promoted colony formation and viability in mouse CFs, while HOXA11‑AS knockdown had the opposite effect. In addition, overexpression of HOXA11‑AS increased cell migration and invasion in the Transwell assays, whereas expression knockdown decreased the metastatic ability of cells. In order to explore the detailed mechanism, co‑transfection of HOXA11‑AS expression plasmid and siTGFβ1 into CFs resulted in increased cell proliferative rate and cell metastasis through the TGFβ1 signaling pathway. Taken together, the present study suggested that the lncRNA HOXA11‑AS may be a potential therapeutic target against cardiac fibrosis, and provided a novel insight into the diagnosis and treatment of clinical cardiac fibrosis.

Diagnostic efficacy of long non-coding RNA in lung cancer: a systematic review and meta-analysis

The detection of long non-coding RNA (lncRNA) is a novel method for lung cancer diagnosis. However, the diagnostic efficacy of lncRNA in different studies is inconsistent. Therefore, we conducted this meta-analysis to elucidate the diagnostic efficacy of lncRNA in identification of lung cancer including small cell lung cancer. The online PubMed, Medline, EMBASE, CNKI and Wanfang literature databases were searched to identify all related articles about the diagnostic efficacy of lncRNA for lung cancer. 28 articles including 3044 patients with lung cancer and 2598 controls were enrolled in our meta-analysis. lncRNA sustained a high diagnostic efficacy, pooled sensitivity of 0.82 (95% CI 0.79 to 0.84), specificity of 0.82 (95% CI 0.78 to 0.84) and area under the curve (AUC) of 0.88 (95% CI 0.85 to 0.91) in identification of patients with lung cancer from controls. Furthermore, the diagnostic efficacy of paralleled lncRNA was better than single lncRNA (sensitivity: 0.86 vs 0.80; specificity: 0.88 vs 0.78; AUC: 0.93 vs 0.86). MALAT1 had a better diagnostic efficacy than GAS5 (AUC: 0.90 vs 0.81; sensitivity: 0.83 vs 0.70; specificity: 0.83 vs 0.78). lncRNA in tissues was observed to achieve lower diagnostic efficacy than that in plasma or serum (AUC: 0.87 vs 0.90 vs 0.90) when stratified by sample types. In summary, our meta-analysis suggests that lncRNA might be a promising biomarker(s) for identifying lung cancer and the combination of lncRNA or with other biomarkers had a better diagnostic efficacy.