Long non-coding RNA DLX6-AS1 knockdown suppresses the tumorigenesis and progression of non-small cell lung cancer through microRNA-16-5p/BMI1 axis

The interaction between lncRNAs and transcription factors regulating autophagy in human cancers: A comprehensive and therapeutical survey

Autophagy, as a highly conserved cellular process, participates in cellular homeostasis by degradation and recycling of damaged organelles and proteins. Besides, autophagy has been evidenced to play a dual role through cancer initiation and progression. In the early stage, it may have a tumor-suppressive function through inducing apoptosis and removing damaged cells and organelles. However, late stages promote tumor progression by maintaining stemness features and induction of chemoresistance. Therefore, identifying and targeting molecular mechanisms involved in autophagy is a potential therapeutic strategy for human cancers. Multiple transcription factors (TFs) are involved in the regulation of autophagy by modulating the expression of autophagy-related genes (ATGs). In addition, a wide array of long noncoding RNAs (lncRNAs), a group of regulatory ncRNAs, have been evidenced to regulate the function of these autophagy-related TFs through tumorigenesis. Subsequently, the lncRNAs/TFs/ATGs axis shows great potential as a therapeutic target for human cancers. Therefore, this review aimed to summarize new findings about the role of lncRNAs in regulating autophagy-related TFs with therapeutic perspectives.

The lncRNA DLX6-AS1/miR-16-5p axis regulates autophagy and apoptosis in non-small cell lung cancer: A Boolean model of cell death

Long non-coding RNA (lncRNA) distal-less homeobox 6 antisense RNA 1 (DLX6-AS1) is elevated in a variety of cancers, including non-small cell lung cancer (NSCLC) and cervical cancer. Although it was found that the microRNA-16-5p (miR-16), which is known to regulate autophagy and apoptosis, had been downregulated in similar cancers. Recent research has shown that in tumors with similar characteristics, DLX6-AS1 acts as a sponge for miR-16 expression. However, the cell death-related molecular mechanism of the DLX6-AS1/miR-16 axis has yet to be investigated. Therefore, we propose a dynamic Boolean model to investigate gene regulation in cell death processes via the DLX6-AS1/miR-16 axis. We found the finest concordance when we compared our model to many experimental investigations including gain-of-function genes in NSCLC and cervical cancer. A unique positive circuit involving BMI1/ATM/miR-16 is also something we predict. Our results suggest that this circuit is essential for regulating autophagy and apoptosis under stress signals. Thus, our Boolean network enables an evident cell-death process coupled with NSCLC and cervical cancer. Therefore, our results suggest that DLX6-AS1 targeting may boost miR-16 activity and thereby restrict tumor growth in these cancers by triggering autophagy and apoptosis.

miRNAs and exosomal miRNAs in lung cancer: New emerging players in tumor progression and therapy response

Non-coding RNAs have shown key roles in cancer and among them, short RNA molecules are known as microRNAs (miRNAs). These molecules have length less than 25 nucleotides and suppress translation and expression. The functional miRNAs are produced in cytoplasm. Lung cancer is a devastating disease that its mortality and morbidity have undergone an increase in recent years. Aggressive behavior leads to undesirable prognosis and tumors demonstrate abnormal proliferation and invasion. In the present review, miRNA functions in lung cancer is described. miRNAs reduce/increase proliferation and metastasis. They modulate cell death and proliferation. Overexpression of oncogenic miRNAs facilitates drug resistance and radio-resistance in lung cancer. Tumor microenvironment components including macrophages and cancer-associated fibroblasts demonstrate interactions with miRNAs in lung cancer. Other factors such as HIF-1α, lncRNAs and circRNAs modulate miRNA expression. miRNAs have also value in the diagnosis of lung cancer. Understanding such interactions can pave the way for developing novel therapeutics in near future for lung cancer patients.

Hsa_circ_0102899 promotes epithelial-mesenchymal transition in non-small cell lung cancer

OBJECTIVE

The significance of circular RNAs (circRNAs) has been identified in the progression of non-small cell lung cancer (NSCLC). Consistently, our study probed the functional actions of hsa_circ_0102899 (circ_0102899) in NSCLC cells.

METHODS

circ_0102899 expression was checked in NSCLC tissues, as well as its correlation with clinical characteristics of patients, Using A459 cells, transfection to alter gene expression was performed, thus measuring the changes of proliferation, apoptosis, migration, and apoptosis, as well as epithelial-mesenchymal transition (EMT)-related proteins. circ_0102899's effects in vivo were validated by tumor xenograft assay. Finally, the regulatory mechanism of circ_0102899 was investigated.

RESULTS

circ_0102899 indicated a high-expression level in NSCLC tissues which was associated with NSCLC tumor characteristics. Functionally, circ_0102899 knockdown not only inhibited the growth and EMT process of NSCLC cells, but also inhibited tumor formation in vivo. In terms of the regulatory mechanism, circ_0102899 had a binding to miR-885-5p to target eukaryotic translation initiation factor 4γ2 (EIF4G2). circ_0102899 mediated miR-885-5/EIF4G2 axis to accelerate the process of cell malignant behavior in NSCLC.

CONCLUSION

circ_0102899 promotes EMT and metastasis in NSCLC by regulating the miR-885-5p/EIF4G2 axis.

Various LncRNA Mechanisms in Gene Regulation Involving miRNAs or RNA-Binding Proteins in Non-Small-Cell Lung Cancer: Main Signaling Pathways and Networks

Long non-coding RNAs (lncRNAs) are crucial players in the pathogenesis of non-small-cell lung cancer (NSCLC). A competing binding of lncRNAs and mRNAs with microRNAs (miRNAs) is one of the most common mechanisms of gene regulation by lncRNAs in NSCLC, which has been extensively researched in the last two decades. However, alternative mechanisms that do not depend on miRNAs have also been reported. Among them, the most intriguing mechanism is mediated by RNA-binding proteins (RBPs) such as IGF2BP1/2/3, YTHDF1, HuR, and FBL, which increase the stability of target mRNAs. IGF2BP2 and YTHDF1 may also be involved in m6A modification of lncRNAs or target mRNAs. Some lncRNAs, such as DLGAP1-AS2, MALAT1, MNX1-AS1, and SNHG12, are involved in several mechanisms depending on the target: lncRNA/miRNA/mRNA interactome and through RBP. The target protein sets selected here were then analyzed using the DAVID database to identify the pathways overrepresented by KEGG, Wikipathways, and the Reactome pathway. Using the STRING website, we assessed interactions between the target proteins and built networks. Our analysis revealed that the JAK-STAT and Hippo signaling pathways, cytokine pathways, the VEGFA-VEGFR2 pathway, mechanisms of cell cycle regulation, and neovascularization are the most relevant to the effect of lncRNA on NSCLC.

linc00511 Knockdown Inhibits Lung Cancer Progression by Regulating miR-16-5p/MMP11

Lung cancer (LC) is a malignant tumor that extremely impairs people. According to numerous studies, long non-coding RNA (lncRNA) was inextricably involved in the advancement of LC. The work aspired to identify linc00511 expression in LC and to dig for the underlying mechanisms linc00511 regulated LC progression. Experimental outcomes revealed that linc00511 was obviously upregulated in LC, and linc00511 knockdown significantly impaired the malignant phenotype of LC cells in vitro. For an in-depth study on the contribution of linc00511 to LC advancement, it was disclosed that miR-16-5p had binding sites to the sequence of linc00511, which also inversely affected linc00511 expression in LC. Further experimental data demonstrated that miR-16-5p directly and negatively targeted matrix metallopeptidase 11 (MMP11). Also, rescue experiments displayed that miR-16-5p inhibition or MMP11 overexpressing offset the suppressive impacts of linc00511 silencing on LC progression. To sum up, our findings indicated that linc00511 performed a crucial role in facilitating LC progression, and mechanistic studies demonstrated that linc00511 aggravated LC progression via targeting the miR-16-5p/MMP11 axis.

METTL3-induced DLGAP1-AS2 promotes non-small cell lung cancer tumorigenesis through m6A/c-Myc-dependent aerobic glycolysis

The critical roles of N6-methyladenosine (m6A) modification have been demonstrated by more and more evidence. However, the cross talk of m6A and long noncoding RNAs (lncRNAs) in non-small cell lung cancer (NSCLC) tumorigenesis is still unclear. Here, this work focused on the functions and molecular mechanism of m6A-modified lncRNA DLGAP1 antisense RNA 2 (DLGAP1-AS2) in NSCLC. Microarray analysis found that lncRNA DLGAP1-AS2 is upregulated in NSCLC cells. Clinical data showed that DLGAP1-AS2 high-expression was correlated with advanced pathological stage and poor prognosis. Functionally, DLGAP1-AS2 overexpression promoted the aerobic glycolysis and DLGAP1-AS2 knockdown suppressed the tumor growth of NSCLC cells. Mechanistically, m6A methyltransferase METTL3 enhanced the stability of DLGAP1-AS2 via m6A site binding. Moreover, DLGAP1-AS2 interacted with YTHDF1 to enhance the stability of c-Myc mRNA through DLGAP1-AS2/YTHDF1/m6A/c-Myc mRNA. In conclusion, our work indicates the functions of m6A-modified DLGAP1-AS2 in the NSCLC aerobic glycolysis, disclosing a potential m6A-dependent manner for NSCLC treatment.

Strategies of LncRNA DLX6-AS1 on Study and Therapeutics

Accumulating evidence has revealed the vital regulatory roles of lncRNA DLX6-AS1 in various tumors at pre-transcriptional, transcriptional, and post-transcriptional levels, which makes it a potential prognosis factor and therapeutic target. In addition, the presence of lncRNA DLX6-AS1 in the exosomes of peripheral blood of patients with tumors may also contribute to it being a possible cancer-related biomarker. However, most literature studies are devoted to studying the effect of lncRNA DLX6-AS1 as a sponging molecule of miRNAs, the research of which is likely to get stuck into a dilemma. Literature studies published already have demonstrated an exciting cell malignant phenotype inhibition with the knockdown of lncRNA DLX6-AS1 in various tumor cell lines. With the comprehensive development of delivery systems, high-throughput sequencing, and aptamers, the problems of finding novel research methods and exploring the therapeutic options which are based on lncRNA DLX6-AS1 in vivo could come into a period to deal with. This review aims to summarize the research statuses of lncRNA DLX6-AS1, discuss other study methodologies and therapeutic strategies on it, which might be of help to the deep learning of lncRNA DLX6-AS1 and its application from basic to clinical research.