Long Noncoding RNA GAS5 Inhibits Tumorigenesis and Enhances Radiosensitivity by Suppressing miR-135b Expression in Non-Small Cell Lung Cancer

MicroRNA-135b mainly functions as an oncogene during tumor progression

Late diagnosis is considered one of the main reasons of high mortality rate among cancer patients that results in therapeutic failure and tumor relapse. Therefore, it is needed to evaluate the molecular mechanisms associated with tumor progression to introduce efficient markers for the early tumor detection among cancer patients. The remarkable stability of microRNAs (miRNAs) in body fluids makes them potential candidates to use as the non-invasive tumor biomarkers in cancer screening programs. MiR-135b has key roles in prognosis and survival of cancer patients by either stimulating or inhibiting cell proliferation, invasion, and angiogenesis. Therefore, in the present review we assessed the molecular biology of miR-135b during tumor progression to introduce that as a novel tumor marker in cancer patients. It has been reported that miR-135b mainly acts as an oncogene by regulation of transcription factors, signaling pathways, drug response, cellular metabolism, and autophagy. This review paves the way to suggest miR-135b as a tumor marker and therapeutic target in cancer patients following the further clinical trials and animal studies.

Exploring the enigma: history, present, and future of long non-coding RNAs in cancer

Long noncoding RNAs (lncRNAs), which are more than 200 nucleotides in length and do not encode proteins, play crucial roles in governing gene expression at both the transcriptional and posttranscriptional levels. These molecules demonstrate specific expression patterns in various tissues and developmental stages, suggesting their involvement in numerous developmental processes and diseases, notably cancer. Despite their widespread acknowledgment and the growing enthusiasm surrounding their potential as diagnostic and prognostic biomarkers, the precise mechanisms through which lncRNAs function remain inadequately understood. A few lncRNAs have been studied in depth, providing valuable insights into their biological activities and suggesting emerging functional themes and mechanistic models. However, the extent to which the mammalian genome is transcribed into functional noncoding transcripts is still a matter of debate. This review synthesizes our current understanding of lncRNA biogenesis, their genomic contexts, and their multifaceted roles in tumorigenesis, highlighting their potential in cancer-targeted therapy. By exploring historical perspectives alongside recent breakthroughs, we aim to illuminate the diverse roles of lncRNA and reflect on the broader implications of their study for understanding genome evolution and function, as well as for advancing clinical applications.

Targeting microRNAs as a promising anti-cancer therapeutic strategy against traffic-related air pollution-mediated lung cancer

Air pollutants are increasingly emitted into the atmosphere because of the high dependency of humans on fossil-derived fuels. Wind speed and direction assisted high dispersibility and uncontrolled nature of air pollution across geo-/demographical borders, making it one of the major global concerns. Besides climate change, air pollution has been found to be associated with various diseases, such as cancer. Lung cancer, which is the world's most common type of cancer, has been found to be associated with traffic-related air pollution. Research and political efforts have been taken to explore green/renewable energy sources. However, these efforts at the current intensity cannot cope with the increasing need for fossil fuels. More specifically, political tensions such as the Russian-Ukraine war, economic tension (e.g., China-USA economic tensions), and other issues (e.g., pandemic, higher inflation rate, and poverty) significantly hindered phasing out fossil fuels. In this context, an increasing global population will be exposed to traffic-related air pollution, which justifies the current uptrend in the number of lung cancer patients. To combat this health burden, novel treatments with higher efficiency and specificity must be designed. One of the potential "life changer" options is microRNA (miRNA)-based therapy to target the expression of oncogenic genes. That said, this review discusses the association of traffic-related air pollution with lung cancer, the changes in indigenous miRNAs in the body during lung cancer, and the current status of miRNA therapeutics for lung cancer treatment. We believe that the article will significantly appeal to a broad readership of oncologists, environmentalists, and those who work in the field of (bio)energy. It may also gain the policymakers' attention to establish better health policies and regulations about air pollution, for example, by promoting (bio)fuel exploration, production, and consumption.

Modulation of long noncoding RNAs by polyphenols as a novel potential therapeutic approach in lung cancer: A comprehensive review

Lung cancer stands as a formidable global health challenge, necessitating innovative therapeutic strategies. Polyphenols, bioactive compounds synthesized by plants, have garnered attention for their diverse health benefits, particularly in combating various cancers, including lung cancer. The advent of whole-genome and transcriptome sequencing technologies has illuminated the pivotal roles of long noncoding RNAs (lncRNAs), operating at epigenetic, transcriptional, and posttranscriptional levels, in cancer progression. This review comprehensively explores the impact of polyphenols on both oncogenic and tumor-suppressive lncRNAs in lung cancer, elucidating on their intricate regulatory mechanisms. The comprehensive examination extends to the potential synergies when combining polyphenols with conventional treatments like chemotherapy, radiation, and immunotherapy. Recognizing the heterogeneity of lung cancer subtypes, the review emphasizes the need for the integration of nanotechnology for optimized polyphenol delivery and personalized therapeutic approaches. In conclusion, we collect the latest research, offering a holistic overview of the evolving landscape of polyphenol-mediated modulation of lncRNAs in lung cancer therapy. The integration of polyphenols and lncRNAs into multidimensional treatment strategies holds promise for enhancing therapeutic efficacy and navigating the challenges associated with lung cancer treatment.

Non-coding RNAs and exosomal non-coding RNAs in lung cancer: insights into their functions

Lung cancer is the second most common form of cancer worldwide Research points to the pivotal role of non-coding RNAs (ncRNAs) in controlling and managing the pathology by controlling essential pathways. ncRNAs have all been identified as being either up- or downregulated among individuals suffering from lung cancer thus hinting that they may play a role in either promoting or suppressing the spread of the disease. Several ncRNAs could be effective non-invasive biomarkers to diagnose or even serve as effective treatment options for those with lung cancer, and several molecules have emerged as potential targets of interest. Given that ncRNAs are contained in exosomes and are implicated in the development and progression of the malady. Herein, we have summarized the role of ncRNAs in lung cancer. Moreover, we highlight the role of exosomal ncRNAs in lung cancer.

LncRNA GAS5 regulated by FTO-mediated m6A demethylation promotes autophagic cell death in NSCLC by targeting UPF1/BRD4 axis

Long non-coding RNA (lncRNA) growth arrest-specific transcript 5 (GAS5) has been shown to be a regulator for many cancers, including non-small cell lung cancer (NSCLC). Therefore, its role and mechanism in the process of NSCLC deserve to be further revealed. The expression levels of GAS5, fat mass and obesity-associated protein (FTO) and bromodomain-containing protein 4 (BRD4) were detected by quantitative real-time PCR. Western blot analysis was used to examine the protein expression of FTO, BRD4, up-frameshift protein 1 (UPF1) and autophagy-related markers. Methylated RNA immunoprecipitation was used to assess the m6A level of GAS5 regulated by FTO. Cell proliferation and apoptosis were determined using MTT assay, EdU assay and flow cytometry. Autophagy ability was assessed by immunofluorescence staining and transmission electron microscope. Xenograft tumor model was constructed to explore the effects of FTO and GAS5 on NSCLC tumor growth in vivo. The interaction between UPF1 and GAS5 or BRD4 was confirmed by pull-down assay, RIP assay, dual-luciferase reporter assay, and chromatin immunoprecipitation. Fluorescent in situ hybridization was used to analyze the co-localization of GAS5 and UPF1. Actinomycin D treatment was employed to evaluate BRD4 mRNA stability. GAS5 was downregulated in NSCLC tissues and was associated with poor prognosis in NSCLC patients. FTO was highly expressed in NSCLC, and it inhibited GAS5 expression by reducing GAS5 m6A methylation level. GAS5 suppressed by FTO could promote the autophagic death of NSCLC cells in vitro and inhibit NSCLC tumor growth in vivo. In addition, GAS5 was able to interact with UPF1 to reduce the mRNA stability of BRD4. Knockdown of BRD4 reversed the inhibition of GAS5 or UPF1 silencing on the autophagic cell death of NSCLC. The findings of the study showed that lncRNA GAS5 mediated by FTO could contribute to the autophagic cell death of NSCLC by interacting with UPF1 to reduce BRD4 mRNA stability, suggesting that GAS5 might be a vital therapy target for NSCLC progression.

Role of Sox9 in BPD and its effects on the Wnt/β-catenin pathway and AEC-II differentiation

The excessive activation of the Wnt/β-catenin signaling pathway is an important regulatory mechanism that underlies the excessive proliferation and impaired differentiation of type 2 alveolar epithelial cells (AEC-II) in bronchopulmonary dysplasia (BPD). Sox9 has been shown to be an important repressor of the Wnt/β-catenin signaling pathway and plays an important regulatory role in various pathophysiological processes. We found that the increased expression of Sox9 in the early stages of BPD could downregulate the expression of β-catenin and promote the differentiation of AEC-II cells into AEC-I, thereby alleviating the pathological changes in BPD. The expression of Sox9 in BPD is regulated by long noncoding RNA growth arrest-specific 5. These findings may provide new targets for the early intervention of BPD.

Non-Coding RNAs as Key Regulators in Lung Cancer

For several decades, most lung cancer investigations have focused on the search for mutations in candidate genes; however, in the last decade, due to the fact that most of the human genome is occupied by sequences that do not code for proteins, much attention has been paid to non-coding RNAs (ncRNAs) that perform regulatory functions. In this review, we principally focused on recent studies of the function, regulatory mechanisms, and therapeutic potential of ncRNAs including microRNA (miRNA), long ncRNA (lncRNA), and circular RNA (circRNA) in different types of lung cancer.

Integrated multi-omics analysis for lung adenocarcinoma in Xuanwei, China

BACKGROUND

Xuanwei lung cancer (XWLC) is well-known for its high incidence and mortality. However, the molecular mechanism is still unclear.

METHODS

We performed a comprehensive transcriptomic, proteomic, and phosphoproteomic characterization of tumors and matched normal adjacent tissues from three XWLC patients with lung adenocarcinoma (LUAD).

RESULTS

Integrated transcriptome and proteome analysis revealed dysregulated molecules and pathways in tumors and identified enhanced metabolic-disease coupling. Non-coding RNAs were widely involved in post-transcriptional regulatory mechanisms to coordinate the progress of LUAD and partially explained the molecular differences between RNA and protein expression patterns. Phosphoproteome provided evidence support for new phosphate sites, reporting the potential roles of core kinase family members and key kinase pathways involved in metabolism, immunity, and homeostasis. In addition, by comparing with the previous LUAD researches, we emphasized the higher degree of oxidative phosphorylation in Xuanwei LUAD and pointed that VIPR1 deficiency aggravated metabolic dysfunction.

CONCLUSION

Our integrated multi-omics analysis provided a powerful resource for a systematic understanding of the molecular structure of XWLC and proposed therapeutic opportunities based on redox metabolism.

Comprehensive landscape and future perspective of long noncoding RNAs in non-small cell lung cancer: it takes a village

Long noncoding RNAs (lncRNAs) are a distinct subtype of RNA that lack protein-coding capacity but exert significant influence on various cellular processes. In non-small cell lung cancer (NSCLC), dysregulated lncRNAs act as either oncogenes or tumor suppressors, contributing to tumorigenesis and tumor progression. LncRNAs directly modulate gene expression, act as competitive endogenous RNAs by interacting with microRNAs or proteins, and associate with RNA binding proteins. Moreover, lncRNAs can reshape the tumor immune microenvironment and influence cellular metabolism, cancer cell stemness, and angiogenesis by engaging various signaling pathways. Notably, lncRNAs have shown great potential as diagnostic or prognostic biomarkers in liquid biopsies and therapeutic strategies for NSCLC. This comprehensive review elucidates the significant roles and diverse mechanisms of lncRNAs in NSCLC. Furthermore, we provide insights into the clinical relevance, current research progress, limitations, innovative research approaches, and future perspectives for targeting lncRNAs in NSCLC. By summarizing the existing knowledge and advancements, we aim to enhance the understanding of the pivotal roles played by lncRNAs in NSCLC and stimulate further research in this field. Ultimately, unraveling the complex network of lncRNA-mediated regulatory mechanisms in NSCLC could potentially lead to the development of novel diagnostic tools and therapeutic strategies.

Long non-coding RNAs in non-small cell lung cancer: implications for preventing therapeutic resistance

Lung cancer has the highest mortality and morbidity rates among all cancers worldwide. Despite many complex treatment options, including radiotherapy, chemotherapy, targeted drugs, immunotherapy, and combinations of these treatments, efficacy is low in cases of resistance to therapy, metastasis, and advanced disease, contributing to low overall survival. There is a pressing need for the discovery of novel biomarkers and therapeutic targets for the early diagnosis of lung cancer and to determine the efficacy and outcomes of drug treatments. There is now substantial evidence for the diagnostic and prognostic value of long noncoding RNAs (lncRNAs). This review briefly discusses recent findings on the roles and mechanisms of action of lncRNAs in the responses to therapy in non-small cell lung cancer.

Long non-coding RNAs in lung cancer: Unraveling the molecular modulators of MAPK signaling

Lung cancer (LC) continues to pose a significant global medical burden, necessitating a comprehensive understanding of its molecular foundations to establish effective treatment strategies. The mitogen-activated protein kinase (MAPK) signaling system has been scientifically associated with LC growth; however, the intricate regulatory mechanisms governing this system remain unknown. Long non-coding RNAs (lncRNAs) are emerging as crucial regulators of diverse cellular activities, including cancer growth. LncRNAs have been implicated in LC, which can function as oncogenes or tumor suppressors, and their dysregulation has been linked to cancer cell death, metastasis, spread, and proliferation. Due to their involvement in critical pathophysiological processes, lncRNAs are gaining attention as potential candidates for anti-cancer treatments. This article aims to elucidate the regulatory role of lncRNAs in MAPK signaling in LC. We provide a comprehensive review of the key components of the MAPK pathway and their relevance in LC, focusing on aberrant signaling processes associated with disease progression. By examining recent research and experimental findings, this article examines the molecular mechanisms through which lncRNAs influence MAPK signaling in lung cancer, ultimately contributing to tumor development.

Evaluation of Circ_0000977-Mediated Regulatory Network in Breast Cancer: A Potential Discriminative Biomarker for Triple-Negative Tumors

Previous investigations have revealed that circular RNAs (circRNAs) play pivotal roles in cancer development and progression by participating in several biological procedures, such as competing endogenous RNA (ceRNA) networks. Recently, circRNAs have been proposed as non-invasive, stable, and affordable cell-free biomarkers for cancer screening and test monitoring. Although, their clinical usefulness vastly remains to be evaluated in breast cancer (BC). Triple-negative breast cancer (TNBC), as the most challenging BC subtype, is an urgent requirement of identifying specific biomarkers and discovering the molecular mechanisms that lead to aggressive behaviors of tumor cells. The therapeutic strategies for TN patients have remained limited due to the impracticality of endocrine therapies and a remarkable portion of patients with TNBC experience recurrence, chemoresistance, and metastasis. TNBC Microarray expression profile analysis found that circ_0000977 is one of the most dysregulated circRNA in TNBC in comparison with non-TNBC. It could be a clue referring to the potential clinical utility of circ_0000977 in TNBC. The current study aims to assess the clinical implications and potential ceRNA regulatory network of circ_0000977 in TNBC. We confirmed circ_0000977 down-regulation in TNBC cell lines and tumors versus non-TNBC samples by real-time PCR. Subsequently, an assessment of the diagnostic value of circ_0000977 in plasma samples from triple-negative patients revealed a potential diagnostic cell-free biomarker in triple-negative BC. Finally, our integrative approach uncovered potential circ-0000977/miR-135b-5p/mRNAs regulatory network in TNBC. The inhibitory effect of miR-135b-5p on its downstream mRNAs was assessed by knocking down it in MDA-MB-231 cells. Functional and correlation analyses revealed APC and GATA3 could be regulated by circ_0000977/miR-135b-5p ceRNA axis, which presents valuable insight into circ-0000977-mediated gene silencing involved in the ceRNA network of TNBC. This study uncovered the potential clinical implication of circ_0000977 for the diagnosis and treatment of TNBC patients.

A review on the importance of miRNA-135 in human diseases

MicroRNA-135 (miR-135) is a microRNA which is involved in the pathoetiology of several neoplastic and non-neoplastic conditions. Both tumor suppressor and oncogenic roles have been reported for this miRNA. Studies in prostate, renal, gallbladder and nasopharyngeal cancers as well as glioma have shown down-regulation of miR-135 in cancerous tissues compared with controls. These studies have also shown the impact of miR-135 down-regulation on enhancement of cell proliferation and aggressive behavior. Meanwhile, miR-135 has been shown to be up-regulated in bladder, oral, colorectal and liver cancers. Studies in breast, gastric, lung and pancreatic cancers as well as head and neck squamous cell carcinoma have reported dual roles for miR-135. Dysregulation of miR-135 has also been noted in various non-neoplastic conditions such as Alzheimer’s disease, atherosclerosis, depression, diabetes, Parkinson, pulmonary arterial hypertension, nephrotic syndrome, endometriosis, epilepsy and allergic conditions. In the current review, we summarize the role of miR-135 in the carcinogenesis as well as development of other disorders.

LncRNA in tumorigenesis of non-small-cell lung cancer: From bench to bedside

Lung cancer has been one of the leading causes of cancer-related death worldwide, and non-small-cell lung cancer (NSCLC) accounts for the majority of lung cancer morbidity, yet the pathogenesis of NSCLC has not been fully elucidated. Recently, long-chain non-coding RNA (lncRNA) has attracted widespread attention. LncRNA is a type of non-coding RNA whose transcript length exceeds 200 nucleotides. After constant research, academics updated their understanding of lncRNA, especially its role in the biological processes of cancer cells, including epigenetic regulation, cell proliferation, and cell differentiation. Notably, examination of lncRNAs could serve as potential hallmarks for clinicopathological features, long-term prognosis, and drug sensitivity. Therefore, it is necessary to explore the functions of lncRNA in NSCLC and innovate potential strategies against NSCLC based on lncRNA-related research. Herein, we reviewed the functions of lncRNA in the occurrence, diagnosis, treatment, and prognosis of NSCLC, which not only help promote a comprehensive view of lncRNA in NSCLC, but also shed light on the potential of lncRNA-based diagnosis and treatment of NSCLC.

Long noncoding RNAs (lncRNAs) in human lymphomas

Lymphomas are a diverse group of haematologic malignancies, which occur in infection-fighting cells of the lymphatic system. Long non-coding RNAs (lncRNAs) are non-coding RNAs, which have recently received significant attention as the main mediators of gene expression. In this review, we summarize the current knowledge on lncRNAs involved in lymphomas, their molecular functions, as well as their potential clinical value. Relevant literature was identified by a PubMed search of English language papers using the following terms: Lymphoma, LncRNA, leukemia, proliferation, apoptosis, and prognosis. LncRNAs are imperative for lymphoma carcinogenesis through affecting apoptosis, cell proliferation, invasion, and response to chemotherapy. The expression level of lncRNAs can affect chemotherapy-induced apoptosis. Taken together, lncRNA dysregulation in lymphoma cells is not only an epiphenomenon but also lncRNA transcription is critically related to the initiation and progression of lymphomas. Aberrant expression of lncRNAs can lead to the transformation of normal lymphocytes into lymphoma cells.

Research Progress of Long Non-Coding RNA GAS5 in Malignant Tumors

With completing the whole genome sequencing project, awareness of lncRNA further deepened. The growth arrest-specific transcript 5 (GAS5) was initially identified in growth-inhibiting cells. GAS5 is a lncRNA (long non-coding RNA), and it plays a crucial role in various human cancers. There are small ORFs (open reading frames) in the exons of the GAS5 gene sequence, but they do not encode functional proteins. In addition, GAS5 is also the host gene of several small nucleolar RNAs (snoRNA). These snoRNAs are believed to play a suppressive role during tumor progression by methylating ribosomal RNA (rRNA). As a result, GAS5 expression levels in tumor tissues are significantly reduced, leading to increased malignancy, poor prognosis, and drug resistance. Recent studies have demonstrated that GAS5 can interact with miRNAs by base-pairing and other functional proteins to inhibit their biological functions, impacting signaling pathways and changing the level of intracellular autophagy, oxidative stress, and immune cell function in vivo. In addition, GAS5 participates in regulating proliferation, invasion, and apoptosis through the above molecular mechanisms. This article reviews the recent discoveries on GAS5, including its expression levels in different tumors, its biological behavior, and its molecular regulation mechanism in human cancers. The value of GAS5 as a molecular marker in the prevention and treatment of cancers is also discussed.

The histidine phosphatase LHPP: an emerging player in cancer

Cancers continue to have high incidence and mortality rates worldwide. Therefore, cancer control remains the main public health goal. Growing research evidence suggests that phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP) plays an important role in inhibiting tumor cell progression. It has been reported in the literature that LHPP is expressed at low levels in tumor tissues and cells and that patients with low LHPP expression have a poorer prognosis. Functional studies have shown that LHPP can inhibit tumor cell proliferation, metastasis, and apoptosis by affecting different target genes. In addition, researchers have used iDPP nanoparticles to deliver LHPP plasmids to treat tumors, demonstrating the great potential of LHPP plasmids for cancer therapy. In our review, we highlight the biological functions and important downstream target genes of LHPP in tumors, providing a theoretical basis for the treatment of human cancers. Although not thoroughly studied in terms of tumor mechanisms, LHPP still represents a promising and effective anticancer drug target.

Potentials of long non-coding RNAs as biomarkers of colorectal cancer

Colorectal cancer (CRC) is the third most common malignant tumor worldwide and the fourth major cause of cancer-related death, with high morbidity and increased mortality year by year. Although significant progress has been made in the therapy strategies for CRC, the great difficulty in early diagnosis, feeble susceptibility to radiotherapy and chemotherapy, and high recurrence rates have reduced therapeutic efficacy resulting in poor prognosis. Therefore, it is urgent to understand the pathogenesis of CRC and unravel novel biomarkers to improve the early diagnosis, treatment and prediction of CRC recurrence. Long non-coding RNAs (lncRNAs) are non-coding RNAs with a length of more than 200 nucleotides, which are abnormally expressed in tumor tissues and cell lines, activating or inhibiting specific genes through multiple mechanisms including transcription and translation. A growing number of studies have shown that lncRNAs are important regulators of microRNAs (miRNAs, miRs) expression in CRC and may be promising biomarkers and potential therapeutic targets in the research field of CRC. This review mainly summarizes the potential application value of lncRNAs as novel biomarkers in CRC diagnosis, radiotherapy, chemotherapy and prognosis. Additionally, the significance of lncRNA SNHGs family and lncRNA-miRNA networks in regulating the occurrence and development of CRC is mentioned, aiming to provide some insights for understanding the pathogenesis of CRC and developing new diagnostic and therapeutic strategies.

The Mechanism of Long Non-coding RNA in Cancer Radioresistance/Radiosensitivity: A Systematic Review

Background and purpose: Radioresistance remains a significant challenge in tumor therapy. This systematic review aims to demonstrate the role of long non-coding RNA (lncRNA) in cancer radioresistance/radiosensitivity.

Material and methods: The electronic databases Pubmed, Embase, and Google Scholar were searched from January 2000 to December 2021 to identify studies addressing the mechanisms of lncRNAs in tumor radioresistance/sensitivity, each of which required both in vivo and in vitro experiments.

Results: Among the 87 studies identified, lncRNAs were implicated in tumor radioresistance/sensitivity mainly in three paradigms. 1) lncRNAs act on microRNA (miRNA) by means of a sponge, and their downstream signals include some specific molecular biological processes (DNA repair and chromosome stabilization, mRNA or protein stabilization, cell cycle and proliferation, apoptosis-related pathways, autophagy-related pathways, epithelial-mesenchymal transition (EMT), cellular energy metabolism) and some signaling mediators (transcription factors, kinases, some important signal transduction pathways) that regulate various biological processes. 2) lncRNAs directly interact with proteins, affecting the cell cycle and autophagy to contribute to tumor radioresistance. 3) lncRNAs act like transcription factors to initiate downstream signaling pathways and participate in tumor radioresistance.

Conclusion: lncRNAs are important regulators involved in tumor radioresistance\sensitivity. Different lncRNAs may participate in the radioresistance with the same regulatory paradigm, and the same lncRNAs may also participate in the radioresistance in different ways. Future research should focus more on comprehensively characterizing the mechanisms of lncRNAs in tumor radioresistance to help us identify corresponding novel biomarkers and develop new lncRNA-based methods to improve radioresistance.

Identification and coregulation pattern analysis of long noncoding RNAs following subacute spinal cord injury

Long noncoding RNAs (lncRNAs) have been demonstrated to play critical regulatory roles in posttranscriptional and transcriptional regulation in eukaryotic cells. However, the characteristics of many lncRNAs, particularly their expression patterns in the lesion epicenter of spinal tissues following subacute spinal cord injury (SCI), remain unclear. In this study, we determined the expression profiles of lncRNAs in the lesion epicenter of spinal tissues after traumatic SCI and predicted latent regulatory networks. Standard Allen's drop surgery was conducted on mice, and hematoxylin and eosin staining was used to observe the damaged area. High-throughput sequencing was performed to identify the differential expression profiles of lncRNAs. Quantitative real-time polymerase chain reaction was conducted to evaluate the quality of the sequencing results. Bioinformatics analyses, including Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis, coexpression analysis, and protein-protein interaction analysis, were performed. Targeted binding of lncRNA-miRNA-mRNA was predicted by TargetScan and miRanda. A total of 230 differentially expressed lncRNAs were identified and preliminarily verified, and some potential regulatory networks were constructed. These findings improve our understanding of the mechanisms underlying subacute SCI; differentially expressed lncRNAs are closely involved in pathophysiological processes by regulating multiple pathways. Further studies are essential for revealing the exact mechanism underlying competing endogenous RNA pathways in vivo and in vitro.

Long noncoding RNA Gas5 induces cell apoptosis and inhibits tumor growth via activating the CHOP-dependent endoplasmic reticulum stress pathway in human hepatoblastoma HepG2 cells

In recent years, long noncoding RNAs (lncRNAs) have been demonstrated to be important tumor-associated regulatory factors. LncRNA growth arrest-specific transcript 5 (Gas5) acts as an anti-oncogene in most cancers. Whether Gas5 acts as an oncogene or anti-oncogene in hepatocellular carcinoma (HCC) remains unclear. In the present study, the expression and role of Gas5 in HCC were investigated in vitro and in vivo. Lower expression levels of Gas5 were determined in HCC tissues and cells by quantitative reverse transcription-polymerase chain reaction. Overexpressed Gas 5 lentiviral vectors were constructed to analyze their influence on cell viability, migration, invasion, and apoptosis. Fluorescence in situ hybridization was used to identify the subcellular localization of Gas5. Protein complexes that bound to Gas5 were isolated from HepG2 cells through pull-down experiments and analyzed by mass spectrometry. A series of novel Gas5-interacting proteins were identified and bioinformatics analysis was carried out. These included ribosomal proteins, proteins involved in protein folding, sorting, and transportation in the ER, some nucleases and protein enzymes involved in gene transcription, translation, and other proteins with various functions.78 kDa glucose-regulated protein (GRP78) was identified as a direct target of Gas5 by Rip-qPCR and Western blot analysis assay. Gas5 inhibited HepG2 cell growth and induced cell apoptosis via upregulating CHOP to activate the ER stress signaling pathway. Further studies indicated that the knockdown of CHOP by shRNA partially reversed Gas5-mediated apoptosis in HepG2 cells. Magnetic resonance imaging showed that the ectopic expression of Gas5 inhibited the growth of HCC in nude mice. These findings suggest that Gas5 functions as a tumor suppressor and induces apoptosis through activation of ER stress by targeting the CHOP signal pathway in HCC.

Long Noncoding RNA GAS5: A New Factor Involved in Bone Diseases

Long noncoding RNAs (lncRNAs), as an important type of RNA encoded in the human transcriptome, have shown to regulate different genomic processes in human cells, altering cell type and function. These factors are associated with carcinogenesis, cancer metastasis, bone diseases, and immune system diseases, among other pathologies. Although many lncRNAs are involved in various diseases, the molecular mechanisms through which lncRNAs contribute to regulation of disease are still unclear. The lncRNA growth arrest-specific 5 (GAS5) is a key player that we initially found to be associated with regulating cell growth, differentiation, and development. Further work has shown that GAS5 is involved in the occurrence and prognosis of bone diseases, such as osteoporosis, osteosarcoma, and postosteoporotic fracture. In this review, we discuss recent progress on the roles of GAS5 in bone diseases to establish novel targets for the treatment of bone diseases.

The roles of long non-coding RNAs in lung cancer

Lung cancer is the most common malignancy, being a serious threat of human lives. The incidence and mortality of lung cancer has been increasing rapidly in the past decades. Although the development of new therapeutic modes, such as target therapy, the overall survival rate of lung cancer remains low. It is urgent to advance the understanding of molecular oncology and find novel biomarkers and targets for the early diagnosis, treatment, and prognostic prediction of lung cancer. Long non-coding RNAs (lncRNAs) are non-protein coding RNA transcripts that are more than 200 nucleotides in length. LncRNAs exert diverse biological functions by regulating gene expressions at transcriptional, translational, and post-translational levels. In the past decade, it has been shown that lncRNAs are extensively involved in the pathogenesis of various diseases, including lung cancer. In this review, we highlighted the lncRNAs characterized in lung cancer and discussed their translational potential in lung cancer clinics.

LncRNA GAS5 enhances radiosensitivity of hepatocellular carcinoma and restricts tumor growth and metastasis by miR-144-5p/ATF2

BACKGROUND

This study aimed to evaluate the biologic role of growth arrest-specific 5 (GAS5) in radiosensitivity of hepatocellular carcinoma (HCC).

METHODS

The levels of GAS5, miR-144-5p, and activating transcription factor 2 (ATF2) were quantified in HCC tissues and cell lines. RNA immunoprecipitation (RIP) and RNA pull-down assays were used to test the interaction between GAS5 and miR-144-5p. The regulatory relationship between miR-144-5p and ATF2 was identified by the dual-luciferase reporter (DLR) assay. A nude mouse model of HCC was induced to verify the effect of GAS5 on radiosensitivity of HCC in vivo.

RESULTS

Lower levels of GAS5 and ATF2, and higher levels of miR-144-5p, were found in radiation-resistant human HCC tissues and cell lines. Overexpression of ATF2 or GAS5 enhanced the radiosensitivity of HCC cell lines, while knockdown of ATF2 or GAS5 decreased the radiosensitivity. In addition, GAS5 acted as a miR-144-5p sponge, and miR-144-5p inversely regulated ATF2. Also, GAS5 mediated ATF2 levels through miR-144-5p, and increased the radiosensitivity of HCC by suppressing miR-144-5p both in vivo and in vitro.

CONCLUSION

Overexpression of GAS5 upregulates ATF2 through miR-144-5p and is able to enhance the radiosensitivity of HCC.

LncRNA EGOT/miR-211-5p Affected Radiosensitivity of Rectal Cancer by Competitively Regulating ErbB4

BACKGROUND/AIMS

Long non-coding ribonucleic acids (lncRNAs) are involved in the progression of cancers and affect the response to radiation therapy. This study was to investigate the mechanism of lncRNA EGOT in the radiosensitivity of rectal cancer.

METHODS

The mRNA expression of EGOT, miR-211-5p and ErbB4 in rectal cancer tissues and cells was detected by qRT-PCR. The protein expression of ErbB4 was detected by Western blot. Dual-luciferase reporter assay and ribonucleic acid immunoprecipitation (RIP) were used to confirm the interaction between EGOT and miR-211-5p or miR-211-5p and ErbB4. Transfection technology was used to down-regulate and up-regulate the expression of EGOT and miR-211-5p in rectal cancer cells, respectively. MTT, colony formation and flow cytometry were used to detect the effect of EGOT and miR-211-5p on proliferation, invasion, migration and apoptosis of rectal cancer cells.

RESULTS

The expression of EGOT was up-regulated in rectal cancer tissues and cells, and the expression of EGOT was related to the late stage of pathology. EGOT knockdown inhibited the proliferation and colony formation of rectal cancer cells and induced the apoptosis of rectal cancer cells. Moreover, EGOT knockdown was significantly enhanced the effects of radiotherapy on rectal cancer in vivo and in vitro. Furthermore, EGOT was found to serve as a sponge of miR-211-5p, and ErbB4 was a downstream target of miR-211-5p. EGOT enhanced the expression of ErbB4 by regulating miR-211-5p. MiR-211-5p inhibitor restored the effect of EGOT knockdown on the radiosensitivity of rectal cancer.

CONCLUSION

Down-regulation of EGOT could inhibit the growth of rectal cancer cells by regulating the miR-211-5p/ErbB4 axis and improve the radiosensitivity of rectal cancer cells. EGOT may be a new therapeutic target for rectal cancer.

MiR-129-5p promotes radio-sensitivity of NSCLC cells by targeting SOX4 and RUNX1

BACKGROUND

Dysregulation of microRNAs (miRNAs) figures prominently in radio-sensitivity of non-small cell lung cancer (NSCLC). MiR-129-5p can block the development of a variety of tumors. However, whether miR-129-5p modulates radio-sensitivity of NSCLC cells remains unknown.

OBJECTIVE

This study was aimed to explore the role and the underlying mechanism of miR-129-5p in the radiosensitivity of NSCLC.

METHODS

Radio-resistant NSCLC cell lines (A549-R and H1299-R) were constructed using A549 and H1299 cells. Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to quantify miR-129-5p, SRY-box transcription factor 4 (SOX4) mRNA, and RUNX family transcription factor 1 (RUNX1) mRNA expression levels. Cell apoptosis and cell cycle were detected by flow cytometry. Cell counting kit-8 (CCK-8) assay and colony formation experiments were used to measure cell proliferation. γ-H2AX was examined by Western blot to confirm DNA injury. Dual-luciferase reporter experiments were applied to analyze the interactions among miR-129-5p, RUNX1, and SOX4.

RESULTS

In A549-R and H1299-R cells, compared with the wild type cell lines, miR-129-5p expression was remarkably reduced while SOX4 and RUNX1 expressions were increased. The transfection of miR-129-5p into NSCLC cell lines, markedly induced cell apoptosis, DNA injury, and cell cycle arrest, and inhibited cell proliferation and colony formation. RUNX1 and SOX4 were validated as target genes of miR-129-5p, and the restoration of RUNX1 or SOX4 could counteract the influence of miR-129-5p on A549-R cells.

CONCLUSION

MiR-129-5p sensitizes A549-R and H1299-R cells to radiation by targeting RUNX1 and SOX4.

Upregulation of Long Noncoding RNA_GAS5 Suppresses Cell Proliferation and Metastasis in Laryngeal Cancer via Regulating PI3K/AKT/mTOR Signaling Pathway

BACKGROUND

Laryngeal cancer is one of the most common malignant tumors among head and neck cancers. Accumulating studies have indicated that long noncoding RNAs (lncRNAs) play an important role in laryngeal cancer occurrence and progression, however, the functional roles and relative regulatory mechanisms of lncRNA growth arrest-specific transcript 5 (GAS5) in laryngeal cancer progression remain unclear.

METHODS

The expression of lncRNA GAS5 in both laryngeal cancer tissues and cell lines was evaluated using quantitative reverse transcription-polymerase chain reaction (RT-qPCR) assay. The relationships between lncRNA GAS5 expression and clinical parameters were also analyzed. To determine the biological function of lncRNA GAS5, a lncRNA GAS5-specific plasmid was first transfected into laryngeal cancer cells using lentiviral technology. Cell counting kit-8 assay, flow cytometry, and Transwell assays were used to detect in vitro cell proliferation, apoptosis, cycle distribution, and metastasis abilities, respectively. Furthermore, in vivo cell growth experiments were also performed using nude mice. Additionally, western blotting was performed to identify the underlying regulatory mechanism.

RESULTS

In the current study, lncRNA GAS5 was downregulated in laryngeal cancer tissues and its low expression was closely associated with poor tumor differentiation, advanced TNM stage, lymph node metastasis, and shorter overall survival time. In addition, lncRNA GAS5 upregulation significantly inhibited laryngeal cancer cell proliferation both in vitro and in vivo. Moreover, in response to lncRNA GAS5 overexpression, more laryngeal cancer cells were arrested at the G2/M stage, accompanied by increased cell apoptosis rates and suppressed migration and invasion capacities. Mechanistically, our data showed that the overexpression of lncRNA GAS5 significantly regulated the PI3K/AKT/mTOR signaling pathway.

CONCLUSION

LncRNA GAS5 might act as a suppressor gene during laryngeal cancer development, as it suppressed cell proliferation and metastasis by regulating the PI3K/AKT/mTOR signaling pathway; thus, lncRNA GAS5 is a promising therapeutic biomarker for the treatment of laryngeal cancer.

The long intergenic noncoding RNA GAS5 reduces cisplatin-resistance in non-small cell lung cancer through the miR-217/LHPP axis

Long noncoding RNAs (lncRNAs) are known to exert their effects to tumor progression. In this study, the role of the lncRNA GAS5 (growth arrest specific 5) was confirmed in reducing non-small cell lung cancer (NSCLC) cisplatin (DDP) resistance. In NSCLC tissue samples, GAS5 expression decreased significantly. Low GAS5 levels were positively correlated with NSCLC characteristics including TNM, tumor size and lymphatic metastasis. Functionally, GAS5 significantly reduced NSCLC/DDP cell migration, invasion and epithelial-mesenchymal transition (EMT) progression in vitro. In vivo, GAS5 upregulation inhibited remarkably NSCLC/DDP cell tumor growth. Mechanism analysis suggested that GAS5 was a molecular sponge of miR-217, inhibiting the expression of phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP). In conclusion, this study reveals that the GAS5/miR-217/LHPP pathway reduces NSCLC cisplatin resistance and that LHPP may serve as a potential therapeutic target for NSCLC cisplatin resistance.

Role of circular RNA expression in the pathological progression after spinal cord injury

Differential expression of non-coding RNA after traumatic spinal cord injury (TSCI) is closely related to the pathophysiological process. The purposes of this study were to systematically profile and characterize expression of circular RNA (circRNA) in the lesion epicenter of spinal tissues after TSCI, and predict the structure and potential function of the regulatory circRNA/miRNA network. Forty-eight C57BL/6 mice were randomly and equally assigned to two groups: one subjected to TSCI at T8–10 with an Allen’s drop impactor, and a second subjected to laminectomy without TSCI. Spinal cord samples were stained with hematoxylin and eosin, sequenced, and validated. RNA-Seq, Gene Ontology analysis, Kyoto Encyclopedia of Genes and Genomes analysis, and network analyses (Targetscan and miRanda) were used to predict and annotate the circRNA/miRNA/mRNA network. Luciferase reporter, quantitative reverse transcription polymerase chain reaction, and western blot assays were used to profile expression and regulation patterns of the network in mouse models of TSCI. Hematoxylin-eosin staining revealed severe damage to the blood-spinal cord barrier after TSCI. Differentially expressed circRNA and miRNA profiles were obtained after TSCI; differentially expressed circRNAs, which were abundant in the cytoplasm, were involved in positive regulation of transcription and protein phosphorylation. miR-135b-5p was the most significantly downregulated miRNA after TSCI; circRNAAbca1 and KLF4 were predicted to be its target circRNA and mRNA, respectively. Subsequently, the circAbca1/miR-135b-5P/KLF4 regulatory axis was predicted and constructed, and its targeted binding was verified. After inhibiting circAbca1, GAP43 expression was upregulated. Differential expression of circRNAs might play an important role after TSCI. circAbca1 plays a neuroinhibitory role by targeted binding of the miR-135b-5P/KLF4 axis. The identified circRNA/miRNA/mRNA network could provide the basis for understanding pathophysiological mechanisms underlying TSCI, as well as guide the formulation of related therapeutic strategies. All animal protocols were approved by the Research Ethics Committee of West China Hospital of China (approval No. 2017128) on May 16, 2017.

Emerging role of non-coding RNAs in response of cancer cells to radiotherapy

Radiotherapy is an effective method for treatment of a large proportion of human cancers. Yet, the efficacy of this method is precluded by the induction of radioresistance in tumor cells and the radiation-associated injury of normal cells surrounding the field of radiation. These restrictions necessitate the introduction of modalities for either radiosensitization of cancer cells or protection of normal cells against adverse effects of radiation. Non-coding RNAs (ncRNAs) have essential roles in the determination of radiosensitivity. Moreover, ncRNAs can modulate radiation-induced side effects in normal cells. Several microRNAs (miRNAs) such as miR-620, miR-21 and miR-96-5p confer radioresistance, while other miRNAs including miR-340/ 429 confer radiosensitivity. The expression levels of a number of miRNAs are associated with radiation-induced complications such as lung fibrosis or oral mucositis. The expression patterns of several long non-coding RNAs (lncRNAs) such as MALAT1, LINC00630, HOTAIR, UCA1 and TINCR are associated with response to radiotherapy. Taken together, lncRNAs and miRNAs contribute both in modulation of response of cancer cells to radiotherapy and in protection of normal cells from the associated side effects. The current review provides an overview of the roles of these transcripts in these aspects.

Long non-coding RNAs as potential biomarkers in the prognosis and diagnosis of lung cancer: A review and target analysis

Long non-coding RNAs (lncRNA) have been emerged as a novel class of molecular regulators in cancer. They are dysregulated in many types of cancer; however, there is not enough knowledge available on their expression and functional profiles. Lung cancer is the leading cause of the cancer deaths worldwide. Generally, lncRNAs may be associated with lung tumor pathogenesis and they may act as biomarkers for the cancer prognosis and diagnosis. Compared to other invasive prognostic and diagnostic methods, detection of lncRNAs might be a user-friendly and noninvasive method. In this review article, we selected 27 tumor-associated lncRNAs by literature reviewing to further discussing in detail for using as diagnostic and prognostic biomarkers in lung cancer. Also, in an in silico target analysis, the "Experimentally supported functional regulation" approach of the LncTarD web tool was used to identifying the target genes and regulatory mechanisms of the selected lncRNAs. The reports on diagnostic and prognostic potential of all selected lncRNAs were discussed. However, the target genes and regulatory mechanisms of the 22 lncRNAs were identified by in silico analysis and we found the pathways that are controlled by each target group of lncRNAs. They use epigenetic mechanisms, ceRNA mechanisms, protein interaction and sponge mechanism. Also, 10, 23, 5, and 28 target genes for each of these mechanisms were identified, respectively. Finally, each group of target genes controls 50, 12, 7, and 2 molecular pathways, respectively. In conclusion, LncRNAs could be used as biomarkers in lung cancer due to their roles in control of several signaling pathways related to lung tumors. Also, it seems that lncRNAs, which use epigenetic mechanisms for modulating a large number of pathways, could be considered as important subjects for lung cancer-related diagnostic and prognostic biomarkers.

The ceRNA network of lncRNA and miRNA in lung cancer

Since lung cancer is a major causative for cancer-related deaths, the investigations for discovering biomarkers to diagnose at an early stage and to apply therapeutic strategies have been continuously conducted. Recently, long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) are being exponentially studied as promising biomarkers of lung cancer. Moreover, supportive evidence provides the competing endogenous RNA (ceRNA) network between lncRNAs and miRNAs participating in lung tumorigenesis. This review introduced the oncogenic or tumor-suppressive roles of lncRNAs and miRNAs in lung cancer cells and summarized the involvement of the lncRNA/miRNA ceRNA networks in carcinogenesis and therapeutic resistance of lung cancer.

Long Non-Coding RNA MEG3 Modifies Cell-Cycle, Migration, Invasion, and Proliferation Through AKAP12 by Sponging miR-29c in Meningioma Cells

Meningioma (MEN) is a common central nervous system disease. Accumulating evidence indicated that long non-coding RNA maternally expressed gene 3 (MEG3) participated in the progression of MEN. However, the potential mechanisms of MEG3 in altering the aggressive phenotypes of MEN need further exploration. Levels of MEG3, microRNA (miR)-29c, and A-kinase anchor protein 12 (AKAP12) were determined using quantitative real-time Polymerase Chain Reaction (qRT-PCR) assay. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were performed to verify the relationship between miR-29c and MEG3 or AKAP12. The protein level of AKAP12 was detected by western blot. Moreover, cell-cycle arrest, migration, invasion, and proliferation were assessed by flow cytometry, wound healing, transwell assays, and CCK-8 assay, respectively. Levels of MEG3 and AKAP12 were downregulated, while miR-29c was effectively increased in MEN tissues and cell line. Mechanically, MEG3 was a sponge of miR-29c to regulate the expression of AKAP12. Functionally, increase of MEG3 diminished cell-cycle, migration, invasion, and proliferation in MEN cells, and reintroduction of miR-29c could eliminate these effects. In addition, AKAP12 depletion overturned the inhibitory effects of miR-29c absence on cell-cycle, migration, invasion, and proliferation in vitro. Also, AKAP12 was co-regulated by MEG3/miR-29c axis. MEG3 mediated the aggressive behaviors of MEN cells via miR-29c/AKAP12 axis, supporting that MEG3 served as a promising biomarker for the diagnosis and treatment of human MEN.

miRNA as promising theragnostic biomarkers for predicting radioresistance in cancer: A systematic review and meta-analysis

Radioresistance remains as an obstacle in cancer treatment. This systematic review and meta-analysis aimed to evaluate the association between the expression of miRNAs and responses to radiotherapy and the prognosis of different tumors. In total, 77 miRNAs in 19 cancer types were studied, in which 24 miRNAs were upregulated and 58 miRNAs were downregulated in cancer patients. Five miRNAs were differentially expressed. Moreover, 75 miRNAs were found to be related to radioresistance, while 5 were observed to be related to radiosensitivity. The pooled HR and 95 % confidence interval for the combined studies was 1.135 (0.819-1.574; P-value = 0.4). The HR values of the subgroup analysis for miR-21 (HR = 2.344; 95 % CI: 1.927-2.850; P-value = 0.000), nasopharyngeal carcinoma (HR = 0.448; 95 % CI: 0.265-0.760; P = 0.003) and breast cancer (HR = 1.131; 95 % CI: 0.311-4.109; P = .85) were obtained. Our results highlighted that across the published literature, miRNAs can modulate tumor radioresistance or sensitivity by affecting radiation-related signaling pathways. It seems that miRNAs could be considered as a theragnostic biomarker to predict and monitor clinical response to radiotherapy. Thus, the prediction of radioresistance in malignant patients will improve radiotherapy outcomes and radiotherapeutic resistance.

Long Non-Coding RNA GAS5 Targeting microRNA-21 to Suppress the Invasion and Epithelial-Mesenchymal Transition of Uveal Melanoma

Objective

Human uveal melanoma (UM) is a common ocular malignant tumor with a high risk of metastasis. Emerging evidence indicates that long non-coding RNAs (lncRNAs) are correlated with the development of UM. Here, we aimed to determine the biological significance of lncRNA growth arrest-specific transcript 5 (GAS5) in UM.

Methods

The expression levels of GAS5 and microRNA-21 (miR-21) in UM tissues and cells were detected by qRT-PCR analysis. CCK-8 assay was performed to investigate the viability of UM cells after cell transfections, and the migration and invasion of UM cells were determined by transwell assay. The protein expression levels were detected by Western blot assay. The relationship between miR-21 and GAS5 in UM cells was confirmed by bioinformatics prediction and luciferase report assay.

Results

Our experiments demonstrated that GAS5 was markedly downregulated in UM cells and clinical specimens. Overexpression of GAS5 inhibited, whereas knockdown of GAS5 promoted the viability, migration, and invasion of UM cells. The epithelial-to-mesenchymal transition (EMT) process of UM cells was also suppressed by upregulating of GAS5 and enhanced by downregulating of GAS5. Additionally, as a competitive endogenous RNA (ceRNA), GAS5 directly binded to the oncogenic miR-21 in UM cells, and overexpression of miR-21 attenuated the EMT-suppressing effect of GAS5.

Conclusion

Taken together, our findings suggest that GAS5/miR-21 axis is implicated in the pathogenesis of UM and might serve as a potential therapeutic target.

Long Noncoding RNA PTPRG Antisense RNA 1 Reduces Radiosensitivity of Nonsmall Cell Lung Cancer Cells Via Regulating MiR-200c-3p/TCF4

Background:

PTPRG antisense RNA 1 has been well-documented to exert an oncogenic role in diverse neoplasms. However, the precise role of PTPRG antisense RNA 1 in regulating radiosensitivity of nonsmall cell lung cancer cells remains largely elusive.

Methods:

Expression levels of PTPRG antisense RNA 1 and miR-200c-3p in nonsmall cell lung cancer tissues and cells were detected by quantitative real-time polymerase chain reaction, while transcription factor 4 expression was examined by immunohistochemistry and Western blot. After nonsmall cell lung cancer cells were exposed to X-ray with different doses in vitro, Cell Counting Kit-8 assay and colony formation assay were conducted to determine the influence of PTPRG antisense RNA 1 on cell viability. Interaction between miR-200c-3p and PTPRG antisense RNA 1 as well as transcription factor 4 was investigated by dual luciferase reporter assay.

Result:

In nonsmall cell lung cancer tissues, the expressions of PTPRG antisense RNA 1 and transcription factor 4 were significantly upregulated, whereas the expression of miR-200c-3p was downregulated. It was also proved that PTPRG antisense RNA 1 and 3′-untranslated region of transcription factor 4 can bind to miR-200c-3p. Under X-ray irradiation, overexpressed PTPRG antisense RNA 1 could promote the viability and enhance the radioresistance of nonsmall cell lung cancer cells, and this effect was partially weakened by miR-200c-3p mimics. Transcription factor 4 was identified as a target gene of miR-200c-3p, which could be positively regulated by PTPRG antisense RNA 1.

Conclusion:

PTPRG antisense RNA 1 reduces the radiosensitivity of nonsmall cell lung cancer cells via modulating miR-200c-3p/TCF4 axis.

Knockdown of LINC00473 promotes radiosensitivity of non-small cell lung cancer cells via sponging miR-513a-3p

Non-small cell lung cancer (NSCLC) is the most common form of lung cancer. Radioresistance is a significant obstacle in NSCLC radiotherapy. Long non-coding RNA LINC00473 has been found to impact the radiotherapy in several malignant tumours. This study aimed to investigate the underlying role and mechanism of LINC00473 in regulating radiosensitivity of NSCLC cells. The levels of LINC00473 and miR-513a-3p were measured by quantitative Real-Time PCR. The relationship of LINC00473 with overall survival was tested by the Kaplan-Meier method. The effects of LINC00473 on cell viability and cell survival were assessed by cell counting kit-8 (CCK-8) and colony survival assay in NSCLC cells exposed to different doses of radiation. A luciferase reporter assay was used to investigate the correlation between LINC00473 and miR-513a-3p. The present study showed that the relative LINC00473 expression was upregulated and miR-513a-3p expression was downregulated in radioresistant NSCLC patients compared with radiosensitive patients. And upregulated LINC00473 expression was associated with poor prognosis of NSCLC patients after radiotherapy. Radiation led to an increase in LINC00473 expression in a dose- and time-dependent manner. The knockdown of LINC00473 markedly promoted radiosensitivity in NSCLC cells under different doses of radiation. LINC00473 was a sponge of miR-513a-3p and negatively regulated the miR-513a-3p expression. In conclusion, the inhibition of miR-513a-3p markedly reversed the promoted effect of LINC00473 knockdown on cell radiosensitivity. LINC00473 inhibition enhances radiosensitivity of NSCLC by sponging miR-513a-3p, providing a promising therapeutic target to increase the sensitivity of radiotherapy in NSCLC patients.

The Non-Coding RNA GAS5 and Its Role in Tumor Therapy-Induced Resistance

The growth arrest-specific transcript 5 (GAS5) is a >200-nt lncRNA molecule that regulates several cellular functions, including proliferation, apoptosis, invasion and metastasis, across different types of human cancers. Here, we reviewed the current literature on the expression of GAS5 in leukemia, cervical, breast, ovarian, prostate, urinary bladder, lung, gastric, colorectal, liver, osteosarcoma and brain cancers, as well as its interaction with various miRNAs and its effect on therapy-related resistance in these malignancies. The general consensus is that GAS5 acts as a tumor suppressor across different tumor types and that its up-regulation results in tumor sensitization to chemotherapy or radiotherapy. GAS5 seems to play a previously unappreciated, but significant role in tumor therapy-induced resistance.

A Systematic Analysis of Dysregulated Long Non-Coding RNAs/microRNAs/mRNAs in Lung Squamous Cell Carcinoma

BACKGROUND

Lung squamous cell carcinoma (LUSC) accounts up for approximately 30% of all lung cancers with a high mortality. The study was aimed at finding genes critical in the diagnosis and prognosis of LUSC.

MATERIALS AND METHODS

The differentially expressed (DE) genes (DEGs) and DE lncRNAs (DELs) from 501 LUSC and 49 normal lung tissues, and DE miRNAs (DEMs) from 478 LUSC and 45 normal lung tissues were respectively obtained via the TCGA database. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and co-expression network analyses were performed. Survival analysis and receiver operating characteristic curve of hub mRNAs were also analyzed. Competitive endogenous RNA networks of lncRNAs, miRNAs and mRNAs were constructed.

RESULTS

A total of 5747 DEGs, 378 DEMs and 3141 DELs in LUSC were identified in LUSC. The DEGs including AUARK, CDK1, KIF11 and EXO1 were proven to be significant metastatic indicators in LUSC, and 2 DEGs were significantly associated with the survival in LUSC patients. Some genes might have connections with many other gene nodes through a co-expression network. Four lncRNAs, 2 mRNAs and 2 miRNAs were identified as the candidates for the competitive miRNA-mRNA-lncRNA network and might serve as prognostic markers in LUSC.

CONCLUSIONS

We identified the differentially expressed lncRNAs, miRNAs and mRNAs in LUSC, providing further insights into the molecular mechanism of LUSC tumorigenesis and the potential prognostic biomarkers or therapeutic targets for LUSC.

LncRNA growth arrest-special 5 polymorphisms and predisposition to cancer: A meta-analysis

AIM

The lncRNA growth arrest-special 5 (GAS5) is a critical tumor suppressor lncRNA, and its expression level has been found to be decreased in many types of cancers. So GAS5 polymorphisms are also likely to influence predisposition to many types of malignant diseases. Nevertheless, the relationships between GAS5 polymorphisms and cancer are still controversial. Thus, the authors designed this meta-analysis to get a more statistically reliable conclusion.

METHODS

The authors searched PubMed, Embase, and Web of Science for eligible studies. A total of 12 eligible studies involving 8693 cancer cases and 10,805 controls were pooled and analyzed in this meta-analysis.

RESULTS

Among GAS5 polymorphisms, only GAS5 rs145204276 insertion/deletion polymorphism could be analyzed in a meta-analysis with regard to predisposition to cancer since no any other GAS5 polymorphisms were explored by at least two individual genetic association studies. All eligible studies were found to be of Asian origin. Although the overall pooled meta-analysis results did not show any significant associations between rs145204276 insertion/deletion polymorphism and a predisposition to cancer, rs145204276 insertion/deletion polymorphism was demonstrated to be significantly associated with a predisposition to gastric cancer (dominant comparison: P<0.0001; recessive comparison: P=0.005; over-dominant comparison: P=0.0003; over-dominant comparison: P<0.0001) in Asians in further subgroup analyses.

CONCLUSIONS

This meta-analysis demonstrated that GAS5 rs145204276 insertion/deletion polymorphism was associated with a predisposition to gastric cancer in Asians. Nevertheless, considering that this positive finding was only based on three eligible studies from the same area, future studies with larger sample sizes in other populations are still warranted to test the robustness of our findings.

Long Non-Coding RNA GAS5 Suppresses Tumor Progression and Enhances the Radiosensitivity of Prostate Cancer Through the miR-320a/RAB21 Axis

Background

Long non-coding RNAs (lncRNAs) function as a class of significant mediators in prostate cancer (PCa), and this study mainly discussed the molecular mechanism of lncRNA growth arrest-specific 5 (GAS5) in PCa progression and radiosensitivity.

Materials and Methods

GAS5 and microRNA-320a (miR-320a) levels were determined by quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability and migration were severally examined through 3-(4, 5-dimethylthiazol-2-y1)-2, 5-diphenyl tetrazolium bromide (MTT) and transwell assays. PCa cells were treated with X-ray irradiation. Cell survival and apoptosis rate were assayed using colony formation assay and flow cytometry, respectively. The apoptosis-related protein and Rab GTPase 21 (RAB21) protein levels were measured by Western blot. The relation between miR-320a and GAS5 or RAB21 was assessed via the dual-luciferase reporter assay. The effect of GAS5 on radiosensitivity of PCa in vivo was evaluated by xenotransplantation assay.

Results

GAS5 was down-regulated in PCa tissues and cells. GAS5 overexpression suppressed cell viability and migration while facilitated radiosensitivity of PCa cells. GAS5 was a molecular sponge of miR-320a. The effects of GAS5 up-regulation on PCa cells were accomplished by sponging miR-320a. MiR-320a targeted RAB21 and GAS5 up-regulated RAB21 expression via targeting miR-320a. RAB21 knockdown reversed the effects of miR-320a inhibition on PCa cells. GAS5 promoted the radiosensitivity of PCa by the miR-320a/RAB21 axis in vivo.

Conclusion

Collectively, GAS5 restrained tumor development and expedited the radiosensitivity in PCa by the miR-320a/RAB21 axis, which provided a molecular regulatory mechanism of GAS5/miR-320a/RAB21 in PCa development and radioresistance.

MiR-135b Induces Osteosarcoma Invasion by the Modulation of FOXO-1 and c-Myc

Background: Osteosarcoma (OS) is the most common type of bone malignancy. Many studies have attempted to find the association between microRNAs and cancer-associated processes. Alterations in miRNA expression through genetic or epigenetic changes, impairment of transcription factors, and ectopic expression of miRNAs induce the development and progression of cancer. Although miR-135b has been thoroughly documented as an oncogene in the majority of studies, some controversies remain about the conflicting role of miR-135b as a tumor-suppressor. Objectives: The present study aimed at investigating the oncogenic and/or tumor-suppressing role of miR-135b in human OS. Methods: In this study, 21 OS tissue samples, along with 21 adjacent bone tissues (normal) as control specimens were collected to analyze the expression of miR-135b. The Saos2 cell-line was transiently transfected with the miR-135b mimic and inhibitor to assess its effect on two critical transcription factors, namely FOXO-1 and c-Myc. qRT-PCR was performed to quantify the expression of miR-135b in both OS tissues and the Saos2 cell-line. The MTT, cell migration, and cell invasion assays were used to characterize the miR-135b function. The western blot analysis was carried out to monitor the targets of miR-135b. Finally, the changes in cellular functions such as migration and invasion, following the transfection of miR-135b mimic and inhibitor, were verified. Results: The results showed that in comparison with the adjacent normal bone tissues, the expression of miR-135b was higher in OS tissue samples, which inversely correlated with the expression rate of FOXO-1, whereas the expression of c-Myc had a direct relationship to miR-135b expression. Functionally, the miR-135b mimic led to an increase in cell proliferation, invasion, and migration of OS cancer cells. Conclusions: MiR-135b induces the proliferation and invasion of OS cells by the degradation of FOXO-1 and upregulation of c-Myc.

Long Noncoding RNA GAS5 Promotes Osteogenic Differentiation of Human Periodontal Ligament Stem Cells by Regulating GDF5 and p38/JNK Signaling Pathway

Both extracellular matrix (ECM) and stem cells contribute to the formation of bones. Accumulating evidence proved that the growth differentiation factor 5 (GDF5) plays a vital role in ECM osteogenesis regulation; the use of human periodontal ligament stem cells (hPDLSCs) may contribute to alveolar bone regeneration. Moreover, long noncoding RNAs (lncRNA) serves as a regulator in the growing process of cellular organisms including bone formation. Previous efforts has led us to the discovery that the expression of growth arrest specific transcript 5 (GAS5) changed in the osteogenic differentiation of hPDLSCs. Moreover, the expression of GAS5, as it turns out, is correlated to GDF5. This study attempts to investigate the inner workings of GAS5 in its regulation of osteoblastic differentiation of hPDLSCs. Cell transfection, Alkaline phosphatase (ALP) staining, Alizarin red S (ARS) staining, qRT-PCR, immunofluorescence staining analysis and western blotting were employed in this study. It came to our notice that GAS5 and GDF5 expression increased during osteogenesis induction of hPDLSCs. Knocking down of GAS5 inhibited the osteogenic differentiation of hPDLSCs, whereas overexpressing GAS5 promoted these effects. Molecular mechanism study further demonstrated that overexpressing GAS5 bolsters GDF5 expression and boosts the phosphorylation of JNK and p38 in hPDLSCs, with opposite effects in GAS5 knockdown group. To sum up, long noncoding RNA GAS5 serves to regulate the osteogenic differentiation of PDLSCs via GDF5 and p38/JNK signaling pathway. Our findings expand the theoretical understanding of the osteogenesis mechanism in hPDLSCs, providing new insights into the treatment of bone defects.

Exosomal Long Non-Coding RNAs in Lung Diseases

Within the non-coding genome landscape, long non-coding RNAs (lncRNAs) and their secretion within exosomes are a window that could further explain the regulation, the sustaining, and the spread of lung diseases. We present here a compilation of the current knowledge on lncRNAs commonly found in Chronic Obstructive Pulmonary Disease (COPD), asthma, Idiopathic Pulmonary Fibrosis (IPF), or lung cancers. We built interaction networks describing the mechanisms of action for COPD, asthma, and IPF, as well as private networks for H19, MALAT1, MEG3, FENDRR, CDKN2B-AS1, TUG1, HOTAIR, and GAS5 lncRNAs in lung cancers. We identified five signaling pathways targeted by these eight lncRNAs over the lung diseases mentioned above. These lncRNAs were involved in ten treatment resistances in lung cancers, with HOTAIR being itself described in seven resistances. Besides, five of them were previously described as promising biomarkers for the diagnosis and prognosis of asthma, COPD, and lung cancers. Additionally, we describe the exosomal-based studies on H19, MALAT1, HOTAIR, GAS5, UCA1, lnc-MMP2-2, GAPLINC, TBILA, AGAP2-AS1, and SOX2-OT. This review concludes on the need for additional studies describing the lncRNA mechanisms of action and confirming their potential as biomarkers, as well as their involvement in resistance to treatment, especially in non-cancerous lung diseases.

Long noncoding RNA-GAS5 attenuates progression of glioma by eliminating microRNA-10b and Sirtuin 1 in U251 and A172 cells

Long noncoding RNA (lncRNA) growth arrest-specific 5 (GAS5) is implicated in several cancers via modulating microRNAs (miRs). However, little information is available about the correlation between GAS5 and miR-10b. Therefore, we sought out to investigate the biological role of GAS5-miR-10b node mainly in glioma cells. We artificially modulated GAS5 to explore its roles in viability assayed by cell counting kit-8 (CCK-8), motile activities by 24-Transwell assay, as well as apoptosis by a flow cytometer and Western blot assay. miR-10b and Sirtuin 1 (Sirt1) were quantified by qRT-PCR. After co-transfection, we analyzed the viability, migration, invasion, apoptosis, and Sirt1 expression. Western blot was implemented to detect the phosphorylated forms of PTEN, PI3K, AKT, MEK, and ERK. GAS5 inhibited proliferation and motile behaviors, and fortified apoptosis. As for the viability and motile activities, the property of GAS5 was reversed in miR-10b-replenished U251 and A172 cells, while maintained in miR-10b-deficient cells. Additionally, GAS5-induced apoptosis was abolished by miR-10b overexpression while fortified by miR-10b silence. Besides, GAS5 negatively modulated Sirt1 via miR-10b. Moreover, Sirt1 negatively modulated PTEN and positively mediated the abovementioned regulators. GAS5 represses the process of glioma cells by decreasing miR-10b, which as accompanied by Sirt1 silence-induced inactivation of PTEN/PI3K/AKT and MEK/ERK cascades.

lncRNA PCAT18 inhibits proliferation, migration and invasion of gastric cancer cells through miR-135b suppression to promote CLDN11 expression

BACKGROUND

Gastric cancer is a severe disease with a high occurrence rate worldwide. And lncRNAs are demonstrated to be responsible for cancer growth and metastasis. So, it is of great importance to explore the lncRNAs involved mechanism of gastric cancer occurrence and development deeply.

METHODS

Transfection was conducted to build over-expression and down-expression models. Moreover, RT-qPCR and western blot were used to detect the transcriptional and translational levels. The biological functions such as proliferation, migration and invasion of AGS cells were evaluated by MTT analysis, colony formation assay, scarification detection and transwell assay, respectively. The potential binding of miR-135b and its downstream and upstream molecules was validated by dual luciferase reporter gene assay or RIP. Also, the in-vivo mice model was further used to demonstrate the role of lncRNA PCAT18 in gastric cancer.

RESULTS

PCAT18 down-expression promoted proliferation, migration and invasion of gastric cancer cells. Furtherly, over-expression of miR-135b also promoted these biological characteristics of AGS cells. Importantly, we found that PCAT18 could bind miR-135b which also was bound with CLDN11. We found that miR-135b is negatively correlated with CLDN11; PCAT18 and CLDN11 are positively correlated. Moreover, miR-135b mimics could down-regulate protein level of CLDN11, whereas CLDN11 could reverse this effect. In in-vivo experiment, PCAT18 over-expression restrained tumor growth and metastasis.

CONCLUSIONS

Over-expressed lncRNA PCAT18 inhibits proliferation, migration and invasion of gastric cancer cells through regulation of miR-135b/CLDN11.

miR-212-5p exerts tumor promoter function by regulating the Id3/PI3K/Akt axis in lung adenocarcinoma cells

microRNAs may function as oncogenes or tumor suppressor genes that play crucial roles in human carcinogenesis and cancer development. Growing evidence revealed that the tumor suppressor Id3 is involved in tumor progression, carcinogenesis, and the tumor microenvironment. We identified miR-212-5p as a negative posttranscriptional modulator of Id3. Dual luciferase reporter assay was used to verify that Id3 is a direct target gene of miR-212-5p. Id3 was lowly expressed and miR-212-5p was highly expressed in non-small-cell lung cancer (NSCLC) tissues and cells. In addition, we found that NSCLC patients having a higher level of miR-212-5p expression had a shorter survival time. Besides this, miR-212-5p could directly target Id3 and reduce its expression. miR-212-5p overexpression significantly accelerated cell proliferation, migration, and invasion by reversing the effects of Id3. Id3 overexpression by silencing miR-212-5p expression suppressed phosphatidylinositol 3 kinase (PI3K)/Akt activity and consequently promoted apoptosis and inhibited cell proliferation in lung cancer cells. Consistent with the in vitro results, a xenograft mouse model was used to validate the fact that miR-212-5p could promote tumorigenesis by targeting Id3 and activate the PI3K/Akt pathway in vivo as well. Taken together, the present results indicated that miR-212-5p may be involved in progression of NSCLC through the PI3K/Akt signaling pathway by targeting Id3.

Glycyrrhizin Protects γ-Irradiated Mice from Gut Bacteria-Associated Infectious Complications by Improving miR-222-Associated Gas5 RNA Reduction in Macrophages of the Bacterial Translocation Site

Gut bacteria-associated sepsis is a serious concern in patients with gastrointestinal acute radiation syndrome (GIARS). In our previous studies, gut bacteria-associated sepsis caused high mortality rates in mice exposed to 6-9 Gy of γ-rays. IL-12⁺CD38⁺ iNOS⁺ Mϕ (M1Mϕ) located in the bacterial translocation site (mesenteric lymph nodes [MLNs]) of unirradiated mice were characterized as host defense antibacterial effector cells. However, cells isolated from the MLNs of GIARS mice were mostly CCL1⁺IL-10⁺LIGHT⁺miR-27a⁺ Mϕ (M2bMϕ, inhibitor cells for the M1Mϕ polarization). Reduced long noncoding RNA Gas5 and increased miR-222 expression in MLN-Mϕ influenced by the irradiation were shown to be associated with M2bMϕ polarization. In this study, the mortality of mice exposed to 7 Gy of γ-rays (7 Gy GIARS mice) was completely controlled after the administration of glycyrrhizin (GL), a major active ingredient in licorice root (Glycyrrhiza glabra). Bacterial translocation and subsequent sepsis were minimal in 7 Gy GIARS mice treated with GL. Increased Gas5 RNA level and decreased miR-222 expression were shown in MLN-Mϕ isolated from 7 Gy GIARS mice treated with GL, and these macrophages did not display any properties of M2bMϕ. These results indicate that gut bacteria-associated sepsis in 7 Gy GIARS mice was controlled by the GL through the inhibition of M2bMϕ polarization at the bacteria translocation site. Expression of Ccl1, a gene required for M2bMϕ survival, is silenced in the MLNs of 7 Gy GIARS mice because of Gas5 RNA, which is increased in these cells after the suppression of miR-222 (a Gas5 RNA expression inhibitor) by the GL.