The lncRNA MIR4435-2HG promotes lung cancer progression by activating β-catenin signalling

A Comprehensive Review of Long Non-Coding RNAs in the Cancer-Immunity Cycle: Mechanisms and Therapeutic Implications

Long non-coding RNAs (lncRNAs) have emerged as pivotal regulators of the dynamic interplay between cancer progression and immune responses. This review explored their influence on key processes of the cancer-immunity cycle, such as immune cell differentiation, antigen presentation, and tumor immunogenicity. By modulating tumor escape from the immune response, therapeutic resistance, and tumor-stroma interactions, lncRNAs actively shape the tumor microenvironment. Due to their growing knowledge in the area of immune suppression, directly intervening in the induction of regulatory T cells (Tregs), M2 macrophages, and regulating immune checkpoint pathways such as PD-L1, CTLA-4, and others, lncRNAs can be considered promising therapeutic targets. Advances in single-cell technologies and immunotherapy have significantly expanded our understanding of lncRNA-driven regulatory networks, paving the way for novel precision medicine approaches. Ultimately, we discussed how targeting lncRNAs could enhance cancer immunotherapy, offering new avenues for biomarker discovery and therapeutic intervention.

The Emerging Role of LncRNA AWPPH in Multiple Cancers: A Review Study

Long non-coding RNAs (lncRNAs) are transcribed RNA molecules longer than 200 nucleotides in length that have no protein-coding potential. They are able to react with DNA, RNA, and protein. Hence they involve in regulating gene expression at the epigenetic, transcriptional, post-transcriptional, and translational levels. LncRNAs have been proven to play an important role in human malignancies and prognostic outcomes. In this review, we will comprehensively and functionally discuss the role of a novel identified lncRNA, namely lncRNA WAPPH located on human chromosome 2q13, in various cancers. Increasing research studies have shown that lncRNA AWPPH is deregulated in different malignancies, including breast cancer, gastric cancer, colorectal cancer, ovarian cancer, bladder cancer, leukemia, and others. LncRNA WAPPH serves as an oncogene in tumorigenesis and the development of cancer. Moreover, lncRNA AWPPH is involved in numerous biological processes of solid and blood cancers. Taken together, based on our scrutiny analysis, lncRNA AWPPH can be regarded as a putative biomarker for diagnosis or therapeutic target in human malignancies.

MIR4435-2HG: A novel biomarker for triple-negative breast cancer diagnosis and prognosis, activating cancer-associated fibroblasts and driving tumor invasion through EMT associated with JNK/c-Jun and p38 MAPK signaling pathway activation

BACKGROUND

Breast cancer has the highest incidence rate and causes the most fatalities among all female cancers worldwide. Triple-negative breast cancer (TNBC) is known for its strong invasiveness and higher rates of recurrence. In this research, we aimed to identify MIR4435-2HG as a promising long non-coding RNA (lncRNA) biomarker and therapeutic target for TNBC.

METHODS

Utilizing clinicopathological information and transcriptome data from The Cancer Genome Atlas (TCGA) database, we assessed the clinical relevance of MIR4435-2HG in breast cancer through univariate and multivariate COX regression, receiver operating characteristic (ROC) analysis, as well as Kaplan-Meier survival analysis. To investigate the biological role of MIR4435-2HG in TNBC, we conducted gene set enrichment analysis (GSEA), as well as Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Additionally, we constructed and validated a nomogram to predict disease-free survival (DFS). Both the R package "pRRophetic" and the Tumor Immune Dysfunction and Exclusion (TIDE) algorithm were employed to forecast the sensitivity to different therapeutics between the high- and low-MIR4435-2HG groups. We employed single-cell RNA sequencing analysis and tumor microenvironment infiltration analysis to investigate the potential involvement of MIR4435-2HG in the TNBC tumor microenvironment. Cellular biological behaviors were assessed utilizing CCK-8, transwell assays, and wound-healing assays. Furthermore, we performed RNA-seq, qRT-PCR, and western blotting analyses to elucidate and confirm the specific mechanisms underlying the role of MIR4435-2HG in TNBC.

RESULTS

In our study, we have identified MIR4435-2HG as a significant diagnostic and prognostic factor for TNBC. We observed that MIR4435-2HG is widely expressed and might have a significant impact on the reshaping of the TNBC tumor microenvironment. Patients with TNBC in the high-MIR4435-2HG group may show reduced sensitivity to cisplatin, doxorubicin, and gemcitabine and have an increased propensity for immune escape. Knockdown of MIR4435-2HG inhibits cancer-associated fibroblasts (CAFs) activation. Notably, MIR4435-2HG predominantly enhances the migratory and invasive capabilities of TNBC cells through the epithelial-mesenchymal transition (EMT) process. Mechanistically, we validated that MIR4435-2HG activates the JNK/c-Jun and p38 non-classical MAPK signaling pathway in TNBC cells.

CONCLUSIONS

Our findings highlight the significant potential of MIR4435-2HG as a highly promising biomarker for TNBC. Targeting MIR4435-2HG could represent an appealing therapeutic approach for TNBC.

The long noncoding RNA MIR4435-2HG enhances the migration, promotion, and glycolysis of nonsmall cell lung cancer cells by targeting the miR-371a-5p/SOX2/PI3K/Akt axis

Background

Nonsmall cell lung cancer is a leading cause of cancer-related death worldwide. The long noncoding RNA MIR4435-2HG has been shown to play a carcinogenic role in various cancers. The purpose of this study was to explore the role and regulatory mechanism of MIR4435-2HG in non-small cell lung cancer.

Methods

Quantitative real-time polymerase chain reaction was used to detect MIR4435-2HG and SRY-box transcription factor 2 in nonsmall cell lung cancer cells. Gain- or loss-of-function assays of MIR4435-2HG and SRY-box transcription factor 2 were subsequently conducted. Cell proliferation, apoptosis, migration, glycolysis, and invasion were tested. A nude mouse tumor model was constructed to determine the role of MIR4435-2HG and SRY-box transcription factor 2 in the growth of tumor cells in vivo. Furthermore, the interactions between MIR4435-2HG, miR-371a-5p and SRY-box transcription factor 2 were analyzed via a dual-luciferase reporter gene assay.

Results

Quantitative real-time polymerase chain reaction revealed that MIR4435-2HG and SRY-box transcription factor 2 were upregulated in nonsmall cell lung cancer cells. Forced MIR4435-2HG overexpression led to increased cell proliferation, migration, invasion, and glycolysis and repressed cell apoptosis. Overexpressing MIR4435-2HG promoted SRY-box transcription factor 2 expression and PI3K/Akt/mTOR pathway activation. Downregulating MIR4435-2HG had antitumor effects both in vitro and in vivo. SRY-box transcription factor 2 overexpression mostly reversed the suppressive effects of MIR4435-2HG downregulation. Mechanistic studies revealed that MIR4435-2HG, a competitive endogenous RNA, directly targeted and inhibited miR-371a-5p. Rescue assays revealed that miR-371a-5p overexpression or SRY-box transcription factor 2 downregulation significantly inhibited MIR4435-2HG-mediated oncogenic effects.

Conclusion

MIR4435-2HG promotes nonsmall cell lung cancer cell malignant behaviors and glycolysis by regulating the miR-371a-5p/SOX2 axis.

Current insights and future directions of LncRNA Morrbid in disease pathogenesis

Non-coding RNAs have emerged as important regulators of gene expression and contributors to many diseases. LncRNA Morrbid, a long non-coding RNA, has been widely studied in recent years. Current literature reports that lncRNA Morrbid is involved in various diseases such as tumors, cardiovascular diseases, inflammatory diseases and metabolic disorder. However, controversial conclusions exist in current studies. As a potential therapeutic target, it is necessary to comprehensively review the current evidence. In this work, we carefully review the literature on Morrbid and discuss each of the hot topics related to lncRNA Morrbid.

ncRNAs-mediated TIMELESS overexpression in lung adenocarcinoma correlates with reduced tumor immune cell infiltration and poor prognosis

Lung adenocarcinoma (LUAD) has a poor prognosis. Circadian genes such as TIMELESS have been associated with several pathologies, including cancer. The expression of TIMELESS and the relationship between TIMELESS, infiltration of tumors and prognosis in LUAD requires further investigation. In this study, we investigated the expression of TIMELESS and its association with survival across several types of human cancer using data from The Cancer Genome Atlas (TCGA) and the Genotype-Tissue Expression Program. Noncoding RNAs (ncRNAs) regulating overexpression of TIMELESS in lung adenocarcinoma (LUAD) were explored with expression, correlation, and survival analyses. Immune cell infiltration and biomarkers were analyzed between different TIMELESS expression levels. The relationship between TIMELESS expression and immunophenoscores, which were used to predict response to immunotherapy, was evaluated. TIMELESS was identified as a potential oncogene in LUAD. NcRNA analysis showed MIR4435-2HG/hsa-miR-1-3p may interact with TIMELESS in a competitive endogenous RNA network in LUAD tumor tissues. Most immune cells were significantly decreased in TCGA LUAD tumor tissues with high TIMELESS expression except for CD4+T cells and Th2 cells. TIMELESS expression in LUAD tumor tissues was significantly negatively correlated with neutrophil biomarkers, dendritic cell biomarkers (HLA-DPB1, HLA-DQB1, HLA-DRA, HLA-DPA1, CD1C) and an immunophenoscore that predicted outcomes associated with the use of immune checkpoint inhibitors. These findings imply that ncRNAs-mediated TIMELESS overexpression in LUAD tumor tissues correlated with poor prognosis, reduced immune cell infiltration in the tumor microenvironment, and poor response to immune checkpoint inhibitors.

Biological Roles and Pathogenic Mechanisms of LncRNA MIR4435-2HG in Cancer: A Comprehensive Review

The long non-coding RNA MIR4435-2HG has been confirmed to play a crucial regulatory role in various types of tumors. As a novel type of non-coding RNA, MIR4435-2HG plays a key role in regulating the expression of tumor-related genes, interfering with cellular signaling pathways, and affecting tumor immune evasion. Its unique structure allows it to regulate the expression of various tumor-related genes through different pathways, participating in the regulation of tumor signaling pathways, such as regulating the expression of oncogenes and tumor suppressor genes, influencing the biological behaviors of proliferation, metastasis, and apoptosis in tumors. Numerous studies have found a high expression of MIR4435-2HG in various tumor tissues, closely related to the clinical pathological characteristics of tumors, such as staging, lymph node metastasis and prognosis. Some studies have discovered that MIR4435-2HG can regulate the sensitivity of tumor cells to chemotherapy drugs, affecting tumor cell drug resistance. This provides new insights into overcoming tumor drug resistance by regulating MIR4435-2HG. Therefore, studying its molecular mechanisms, expression regulation, and its relationship with the clinical features of tumors is of great significance for revealing the mechanisms of tumor occurrence and developing new therapeutic targets.

LncRNA MIR4435-2HG drives cancer progression by modulating cell cycle regulators and mTOR signaling in stroma-enriched subtypes of urothelial carcinoma of the bladder

BACKGROUND

The risk for recurrence and metastasis after treatment for urothelial carcinoma of the bladder (UCB) is high. Therefore, identifying efficient prognostic markers and novel therapeutic targets is urgently needed. Several long noncoding RNAs (lncRNAs) have been reported to be correlated with UCB progression. In this study, we found that the subtype-specific lncRNA MIR4435-2 host gene (MIR4435-2HG) plays a novel oncogenic role in UCB.

METHODS

RNA-Seq data of TCGA/BLCA were analyzed. The expression of MIR4435-2HG was measured by qRT-PCR in 16 pairs of bladder cancer tissues and adjacent normal tissues. The clinical relecance of MIR4435-2HG was validated via in situ hybridization performed on an in-house cohort of 116 UCB patient samples. RNA pull-down followed by mass spectrometry was performed to identify MIR4435-2HG-binding proteins. To identify signaling pathways involved in MIR4435-2HG activity, comprehensive in vitro and in vivo studies and RNA-Seq assays were performed using UCB cells in which MIR4435-2HG expression was knocked down or exogenously overexpressed. In addition, we performed RNA immunoprecipitation and Western blot analyses to validate the identified MIR4435-2HG-binding proteins and to determine the molecular mechanisms by which MIR4435-2HG promotes UCB progression.

RESULTS

We found that MIR4435-2HG was significantly upregulated in the stromal-enriched subtype of UCB. Increased MIR4435-2HG expression was positively correlated with a high histological grade, advanced T stages, larger tumors, lymph node metastasis and a poor prognosis. In vitro experiments revealed that MIR4435-2HG expression silencing suppressed cell proliferation and induced apoptosis. Inhibition of MIR4434-2HG delayed xenograft tumor growth, while MIR4435-2HG overexpression reversed the MIR4435-2HG silencing-induced inhibition of UCB tumor phenotype acquisition. Mechanistically, we found that MIR4435-2HG positively regulated the expression of a variety of cell cycle regulators, including BRCA2 and CCND1. Knocking down MIR4435-2HG increased the sensitivity of tumor cells to the VEGFR inhibitor cediranib. Furthermore, we found that MIR4435-2HG regulated mTOR signaling and epithelial-mesenchymal transition (EMT) signaling pathways by modulating the phosphorylation of mTOR, 70S6K and 4EBP1. Finally, we confirmed that MIR4435-2HG enhances tumor metastasis through regulation of the EMT pathway.

CONCLUSIONS

Our data indicate that upregulated MIR4435-2HG expression levels are significantly correlated with a poor prognosis of UCB patients. MIR4435-2HG promotes bladder cancer progression, mediates cell cycle (de)regulation and modulates mTOR signaling. MIR4435-2HG is an oncogenic lncRNA in UCB that may serve as a diagnostic and therapeutic target.

Non-coding RNAs in lung cancer: molecular mechanisms and clinical applications

Lung cancer (LC) is a heterogeneous disease with high malignant degree, rapid growth, and early metastasis. The clinical outcomes of LC patients are generally poor due to the insufficient elucidation of pathological mechanisms, low efficiency of detection and assessment methods, and lack of individualized therapeutic strategies. Non-coding RNAs (ncRNAs), including microRNA (miRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA), are endogenous regulators that are widely involved in the modulation of almost all aspects of life activities, from organogenesis and aging to immunity and cancer. They commonly play vital roles in various biological processes by regulating gene expression via their interactions with DNA, RNA, or protein. An increasing amount of studies have demonstrated that ncRNAs are closely correlated with the initiation and development of LC. Their dysregulation promotes the progression of LC via distinct mechanisms, such as influencing protein activity, activating oncogenic signaling pathways, or altering specific gene expression. Furthermore, some ncRNAs present certain clinical values as biomarker candidates and therapeutic targets for LC patients. A complete understanding of their mechanisms in LC progression may be highly beneficial to developing ncRNA-based therapeutics for LC patients. This review mainly focuses on the intricate mechanisms of miRNA, lncRNA, and circRNA involved in LC progression and discuss their underlying applications in LC treatment.

LncRNAs has been identified as regulators of Myeloid-derived suppressor cells in lung cancer

Lung tumours are widespread pathological conditions that attract much attention due to their high incidence of death. The immune system contributes to the progression of these diseases, especially non-small cell lung cancer, resulting in the fast evolution of immune-targeted therapy. Myeloid-derived suppressor cells (MDSCs) have been suggested to promote the progression of cancer in the lungs by suppressing the immune response through various mechanisms. Herein, we summarized the clinical studies on lung cancer related to MDSCs. However, it is noteworthy to mention the discovery of long non-coding RNAs (lncRNAs) that had different phenotypes and could regulate MDSCs in lung cancer. Therefore, by reviewing the different phenotypes of lncRNAs and their regulation on MDSCs, we summarized the lncRNAs' impact on the progression of lung tumours. Data highlight LncRNAs as anti-cancer agents. Hence, we aim to discuss their possibilities to inhibit tumour growth and trigger the development of immunosuppressive factors such as MDSCs in lung cancer through the regulation of lncRNAs. The ultimate purpose is to propose novel and efficient therapy methods for curing patients with lung tumours.

Hepatic stellate cell-released CXCL1 aggravates HCC malignant behaviors through the MIR4435-2HG/miR-506-3p/TGFB1 axis

Hepatic stellate cell (HSC) activation is a critical event in the development of hepatic fibrosis and hepatocellular carcinoma (HCC). By the release of soluble cytokines, chemokines, and chemotaxis, HSCs affect HCC cell phenotypes through a complex tumor microenvironment. In this study, weighted gene co-expression network analysis (WGCNA) was used to identify the TGF-β signaling pathway as a key signaling pathway in Hep3B cells cultured in HSC conditioned medium. MIR4435-2HG is a hub lncRNA associated with the TGF-β signaling pathway and HSC activation. HSC-condition medium (CM) culture induced HCC cell malignant behaviors, which were partially reversed by MIR4435-2HG silencing. miR-506-3p directly bound to MIR4435-2HG and the 3'UTR of TGFB1. Similarly, overexpression of miR-506-3p also attenuated HSC-CM-induced malignant behavior of HCC cells. In HSC-CM cultured HCC cells, the effects of MIR4435-2HG knockdown on TGFB1 expression and HCC cell phenotypes were partially reversed by miR-506-3p inhibition. HSCs affected HCC cell phenotypes by releasing CXCL1. In an orthotopic xenotransplanted tumor model of HCC cells plus HSCs in mice, CXCR2 knockdown in HCC cells significantly inhibited tumorigenesis, which was partially reversed by MIR4435-2HG overexpression in HCC cells. In HCC tissue samples, the levels of CXCL1, TGF-β1, and MIR4435-2HG were upregulated, while miR-506-3p expression was downregulated. In conclusion, HSC-released CXCL1 aggravated HCC cell malignant behaviors through the MIR4435-2HG/miR-506-3p/TGFB1 axis. In addition to CXCL1, the MIR4435-2HG/miR-506-3p/TGFB1 axis might also be the underlying target for HCC therapy.

Long Noncoding RNA MIR4435-2HG Suppresses Colorectal Cancer Initiation and Progression By Reprogramming Neutrophils

MIR4435-2HG, also known as LINC00978, has previously been described as an oncogenic long noncoding RNA (lncRNA). However, we show here that Mir4435-2hg depletion promoted colorectal tumorigenesis and progression in in vivo models of colitis-associated colorectal cancer, spontaneous intestinal adenomatous polyposis, and subcutaneous tumors. Alteration of MIR4435-2HG in colorectal cancer cells did not change the potential for cell proliferation, migration, or invasion in vitro. RNAscope assays showed that most MIR4435-2HG was located in the tumor stroma, which caused high expression of MIR4435-2HG in colorectal cancer tumor tissue. Transcriptome analysis of colorectal cancer tissues from wild-type and Mir4435-2hg-deficient mice revealed Mir4435-2hg as a tumor suppressor gene that regulated the immune microenvironment. Loss of Mir4435-2hg led to a decline in neutrophils and elevation of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC). In tissue-specific Mir4435-2hg knockout mice, we confirmed that Mir4435-2hg depletion in neutrophils, but not in intestinal epithelial cells, promoted colorectal cancer progression. Mechanistically, Mir4435-2hg depletion enhanced the immunosuppressive ability of PMN-MDSCs by disturbing their fatty acid metabolism. These findings suggest that MIR4435-2HG is a tumor-suppressing lncRNA whose deficiency could increase tumor-infiltrating PMN-MDSCs and enhance the immunosuppressive potential of PMN-MDSCs to promote colorectal cancer development. This provides a theoretical basis for further illustrating the pathogenesis of colorectal cancer and a potential antitumor immunotherapy target.

Transcriptomic Analyses Reveal Long Non-Coding RNA in Peripheral Blood Mononuclear Cells as a Novel Biomarker for Diagnosis and Prognosis of Hepatocellular Carcinoma

Novel biomarkers are highly required for the diagnosis and predicting prognosis of hepatocellular carcinoma (HCC). In this study, we investigated the profiles of long non-coding RNAs (lncRNAs) obtained from the peripheral blood mononuclear cells (PBMCs) of patients with HCC and PBMCs from a co-culture model using transcriptomic analysis. The differentially expressed lncRNAs (DElncRNAs) were then characterized and integrated as cancer-induced lncRNAs. Among them, three up-regulating DElncRNAs including MIR4435-2HG, SNHG9 and lnc-LCP2-1 and one down-regulating, lnc-POLD3-2, were identified. The functional analysis showed that these enriched lncRNAs were mainly associated with carcinogenesis and immune responses. Following further validation in PBMCs samples (100 HBV-related HCC, 100 chronic hepatitis B and 100 healthy controls), MIR4435-2HG, lnc-POLD3-2 and their combination were revealed to be sensitive biomarkers in discriminating HCC from non-HCC (AUROC = 0.78, 0.80, and 0.87, respectively), particularly among individuals with normal serum alpha-fetoprotein levels. Additionally, high circulating SNHG9 expression was shown to be an independent prognostic factor of overall survival in patients with HCC. These results indicate that determining these lncRNAs in PBMCs could serve as novel diagnostic and prognostic biomarkers for HBV-related HCC.

Long non-coding RNA MIR4435-2HG: a key molecule in progression of cancer and non-cancerous disorders

MIR4435-2HG (LINC00978) is a long non-coding RNA (lncRNA) that acts as an oncogene in almost all cancers. This lncRNA participates in the molecular cascades involved in other disorders such as coronary artery diseases, osteonecrosis, osteoarthritis, osteoporosis, and periodontitis. MIR4435-2HG exerts its functions via the spectrum of different mechanisms, including inhibition of apoptosis, sponging microRNAs (miRNAs), promoting cell proliferation, increasing cell invasion and migration, and enhancing epithelial to mesenchymal transition (EMT). MIR4435-2HG can regulate several signaling pathways, including Wnt, TGF-β/SMAD, Nrf2/HO-1, PI3K/AKT, MAPK/ERK, and FAK/AKT/β‑catenin signaling pathways; therefore, it can lead to tumor progression. In the present review, we aimed to discuss the potential roles of lncRNA MIR4435-2HG in developing cancerous and non-cancerous conditions. Due to its pivotal role in different disorders, this lncRNA can serve as a potential biomarker in future investigations. Moreover, it may serve as a potential therapeutic target for the treatment of various diseases.

MIR4435-2HG Is a Potential Pan-Cancer Biomarker for Diagnosis and Prognosis

The lncRNA MIR4435-2 host gene (MIR4435-2HG) is located on human chromosome 2q13, and its expression is up-regulated in 18 tumors. MIR4435-2HG participates in 6 signaling pathways to promote tumorigenesis, including the TGF-β signaling pathway, Wnt/β-catenin signaling pathway, MDM2/p53 signaling pathway, PI3K/AKT signaling pathway, Hippo signaling pathway, and MAPK/ERK signaling pathway. MIR4435-2HG competitively binds with 20 miRNAs to form a complex ceRNA network, thereby regulating the expression of downstream target genes. The high expression of MIR4435-2HG is also closely related to the clinicopathological characteristics and poor prognosis of a variety of tumors. Also, the high expression of MIR4435-2HG in peripheral blood or serum has the value of predicting the risk of 9 tumors. In addition, MIR4435-2HG participates in the mechanism of action of three cancer drugs, including resveratrol for the treatment of lung cancer, cisplatin for non-small cell lung cancer and colon cancer, and carboplatin for triple-negative breast cancer. This article systematically summarizes the diagnostic and prognostic value of MIR4435-2HG in a variety of tumors and outlines the ceRNA network and signaling pathways related to MIR4435-2HG, which will provide potential directions for future MIR4435-2HG research.

MIR4435-2HG：A tumor-associated long non-coding RNA

BACKGROUND

It is well known that the changes in the expression level of LncRNA can affect the progression of tumors, which has caused a great upsurge of research in recent years. More and more LncRNA has been proved to take effect on a series of cancers and can promote tumor growth, migration and invasion. In this review, we aim to clarify the pathophysiological functions of LncRNA -MIR4435-2 HG in multiple tumors can be elucidated.

METHODS

By consulting the literature through PubMed, this paper summarizes the relationship between MIR4435-2HG and tumor and its role in the occurrence and development of cancer, and also expounds the specific molecular mechanism of the effect of MIR4435-2HG on cancer.

RESULTS

MIR4435-2HG can function as an oncogene in a variety of cancers. The expression level was abnormally elevated in a series of cancers, consisting of melanoma gastric cancer, head and neck squamous cell carcinoma, oral squamous cell carcinoma, lung cancer, cervical cancer, prostate carcinoma, ovarian cancer, breast cancer, hepatocellular Carcinoma, clear cell renal cell carcinoma malignant, glioma and colorectal cancer. Moreover, MIR4435-2HG is related to the poor prognosis of a variety of cancers. MIR4435-2HG can also affect tumor proliferation, invasion and apoptosis. In addition, MIR4435-2HG can also enhance the metabolic function of myeloid dendritic cells of elite HIV-1 controllers.

CONCLUSION

MIR4435-2HG affects the development of a variety of cancers. It can act as a clinical marker for early tumor diagnosis and takes effects to tumor targeted therapy.

MIR4435-2HG: A newly proposed lncRNA in human cancer

Long non-coding RNAs (lncRNAs) play important roles in the occurrence and progression of tumors. Extensive research has contributed to the current understanding of the critical roles played by lncRNAs in various cancers. LncRNA MIR4435-2HG has been found to be crucial in many cancers, such as breast, cervical, colorectal, and gastric cancer. Expression of MIR4435-2HG is generally upregulated in cancers and MIR4435-2HG participates in many biological functions through molecular mechanism of competitive endogenous RNA networks. This review profiles recent research findings on the expression, functions, mechanism, and clinical value of MIR4435-2HG in cancer, and serves as a reference for further MIR4435-2HG-related research and clinical trials.

Deciphering the Role of Shugoshin-Like Protein 1 in Lung Adenocarcinoma: A Comprehensive Analysis and In Vitro Study

Shugoshin-like protein 1 (SGO1) has been characterized in its function in correct cell division and its role in centrosome cohesion in the nucleus. However, the underlying biological function and potential mechanisms of SGO1 driving the progression of lung adenocarcinoma remain unclear. In this study, we found that SGO1 was increased in LUAD tissues and cell lines. Upregulation of SGO1 expression was correlated with poor overall survival (OS), disease-free survival (DSS), and progression-free survival (PFS) in patients with LUAD. ROC curve analysis suggested that the AUC value of SGO1 was 0.983. Correlation analysis showed that SGO1 expression was related to immune infiltration in LUAD. Meanwhile, a potential ceRNA network was constructed to identify the lncRNA-MIR4435-2HG/miR-125a-5p/SGO1 regulatory axis in LUAD. Finally, we determine that SGO1 regulated the cell proliferation and cell apoptosis of lung adenocarcinoma in vitro. In conclusion, our data suggested that SGO1 could be a novel prognostic biomarker for lung adenocarcinoma.

Noncoding RNAs of Extracellular Vesicles in Tumor Angiogenesis: From Biological Functions to Clinical Significance

Extracellular vesicles (EVs) act as multifunctional regulators of intercellular communication and are involved in diverse tumor phenotypes, including tumor angiogenesis, which is a highly regulated multi-step process for the formation of new blood vessels that contribute to tumor proliferation. EVs induce malignant transformation of distinct cells by transferring DNAs, proteins, lipids, and RNAs, including noncoding RNAs (ncRNAs). However, the functional relevance of EV-derived ncRNAs in tumor angiogenesis remains to be elucidated. In this review, we summarized current research progress on the biological functions and underlying mechanisms of EV-derived ncRNAs in tumor angiogenesis in various cancers. In addition, we comprehensively discussed the potential applications of EV-derived ncRNAs as cancer biomarkers and novel therapeutic targets to tailor anti-angiogenic therapy.

Effects of IncRNA PROX1-AS1 on Proliferation, Migration, Invasion and Apoptosis of Lung Cancer Cells by Regulating MiR-1305

This paper aims to explore the lncRNA PROX1-AS1 effect on proliferation, migration, invasion, and apoptosis of lung cancer cells together with its targeted regulation on miR-1305. To adopt qRT-PCR to test PROX1-AS1 and miR-1305 expression levels in lung cancer tissues and adjacent tissues. Lung cancer cells A549 were cultured in vitro and randomly divided into several groups, which are si-NC, si-PROX1-AS1, miR-NC, miR-1305, si-PROX1-AS1 plus anti-miR-NC, and si-PROX1-AS1 plus anti-miR-1305. To adopt the CCK-8 method to test cell proliferation and to adopt the Transwell chamber experiment to test cell migration and invasion. To adopt the flow cytometry method to test the apoptosis rate. Through a dual luciferase experiment, we decided to find out the targeting relationship between PROX1-AS1 and miR-1305. Then we adopted the western blot method to test CyclinD1, MMP-2, MMP-9, Bcl-2, p21, and Bax expression levels. Compared with adjacent tissues (P < 0.05), the expression of PROX1-AS1 in lung cancer tissue was remarkably higher, while the expression of miR-1305 was remarkably lower (P < 0.05). After PROX1-AS1 knockdown expression or miR-1305 overexpression, cell activity, migration, and invasion ability were outstandingly lowered (P < 0.05), but the apoptosis rate was obviously raised (P < 0.05), CyclinD1, MMP-2, Bcl-2, and MMP-9 protein data were remarkably reduced (P < 0.05), but p21 and Bax protein conditions were outstandingly enhanced (P < 0.05). The dual luciferase experiment confirmed that PROX1-AS1 had a targeting relationship with miR-1305. After cotransfection with si-PROX1-AS1 and anti-miR-1305, the cell viability, migration and invasion ability were remarkably enhanced (P < 0.05), the apoptosis rate was remarkably reduced (P < 0.05), CyclinD1, MMP-2, Bcl-2, and MMP-9 protein were increased remarkably (P < 0.05), and p21 or Bax protein was lowered remarkably (P < 0.05). On the one hand, PROX1-AS1 can promote lung cancer proliferation, migration, and invasion. On the other hand, it may restrain apoptosis, possibly through inhibiting miR-1305 expression.

LncRNA PTPRG-AS1 facilitates glycolysis and stemness properties of esophageal squamous cell carcinoma cells through miR-599/PDK1 axis

BACKGROUND AND AIM

Esophageal squamous cell carcinoma (ESCC) is the most significant subtype of esophageal cancer featured with high occurrence. Long noncoding RNAs (lncRNAs) have been proved to modulate the biological properties of cancer cells, including cell proliferation, invasion, migration, and apoptosis. LncRNA protein tyrosine phosphatase receptor type G-antisense RNA 1 (PTPRG-AS1) has been reported to play as an oncogene in diverse cancers. However, the detailed function PTPRG-AS1 may exert in ESCC is unclear.

METHODS

PTPRG-AS1 expression in ESCC cells was investigated via quantitative reverse transcription real-time polymerase chain reaction (RT-qPCR). The effects of PTPRG-AS1 on ESCC cell proliferation, migration, glycolysis, and stemness were verified through functional assays. Mechanism assays including RIP assay, RNA pull down assay, and luciferase reporter assays were performed to verify the molecular mechanism of PTPRG-AS1.

RESULTS

PTPRG-AS1 silencing hindered the proliferation, migration, glycolysis and stemness of ESCC cells. PTPRG-AS1 regulated pyruvate dehydrogenase kinase 1 (PDK1) expression via sponging miR-599. The PTPRG-AS1/miR-599/PDK1 axis was further verified to aggravate the progression of ESCC cells.

CONCLUSION

PTPRG-AS1 sponged miR-599 to up-regulate PDK1 expression, thereby promoting the proliferation and migration as well as glycolysis and stemness properties of ESCC cells.

Long Noncoding RNA LOC554202 Predicts a Poor Prognosis and Correlates with Immune Infiltration in Thyroid Cancer

Thyroid cancer (TC) is one of the widely diagnosed carcinomas in women before the age of 30. Nevertheless, there is currently a lack of specific biomarkers for predicting the prognosis of TC. Long noncoding RNAs (lncRNAs) were important regulators in human cancer progression as previously described. Unfortunately, there is little known on these lncRNAs’ functions and molecular mechanisms in TC. In our literature, we found that LOC554202 (MIR31HG) was upregulated in TC samples and correlated with clinicopathological features, including M stage, N stage, and lymph nodes examined status in TC. In addition, we found that LOC554202 overexpression was evidently correlated with high immune infiltrate levels of CD8+ T cells, macrophage, neutrophil, myeloid dendritic cells, and B cells in TC. Knockdown of LOC554202 impeded TC cell proliferation and cycle progression. We found that LOC554202 had an association with metabolic pathways, vesicle-mediated transport, tricarboxylic acid cycle, Hedgehog signaling pathway, and Hippo signaling pathway in TC. Reducing LOC554202 hindered TC cell proliferation and cycle progression. Finally, we found that LOC554202 participated in modulating the expression of the regulators of Hippo signaling and TCA pathway, such as CCND2, CCND3, SDHC, SDHD, SUCLA2, and SUCLG1. We thought that this study would largely enhance our understanding of LOC554202’s functional roles in human TC progression and immune response.

New Insights into the Importance of Long Non-Coding RNAs in Lung Cancer: Future Clinical Approaches

In mammals, a large part of the gene expression products come from the non-coding ribonucleotide sequences of the protein. These short and long sequences are within the range of tens to hundreds of nucleotides, encompassing more than 200 RNA molecules, and their function is known as the molecular structure of long non-coding RNA (lncRNA). LncRNA molecules are unique nucleotides that have a substantial role in epigenetic regulation, transcription, and post-transcriptional modifications in different ways. According to the results of recent studies, lncRNAs have been shown to assume various roles, including tumor suppression or oncogenic functions in common types of cancer such as lung and breast cancer. These non-coding RNAs (ncRNAs) play a pivotal role in activating transcription factors, managing the ribonucleoproteins, the framework for collecting co-proteins, intermittent processing regulations, chromatin status alterations, and maintaining the control within the cell. Cutting-edge technologies have been introduced to disclose several types of lncRNAs within the nucleus and the cytoplasm, which have accomplished important achievements that are applicable in medicine. Due to these efforts, various data centers have been created to facilitate and modify scientific information related to these molecules, including detection, classification, biological evolution, gene status, spatial structure, status, and location of these small molecules. In the present study, we attempt to present the impacts of these ncRNAs on lung cancer with an emphasis on their mechanisms and functions.

Excavating novel diagnostic and prognostic long non-coding RNAs (lncRNAs) for head and neck squamous cell carcinoma: an integrated bioinformatics analysis of competing endogenous RNAs (ceRNAs) and gene co-expression networks

Long non-coding RNAs (lncRNAs) have been demonstrated to fine-tune gene regulations that govern a broad spectrum of oncogenic processes. Nonetheless, our understanding of the roles of lncRNAs and their interactions with miRNAs and mRNAs in HNSCC is still highly rudimentary. Here, we present a comprehensive bioinformatics analysis in which competing endogenous RNA (ceRNA) network construction and weighted gene co-expression network analysis (WGCNA) were combined to explore novel diagnostic and prognostic lncRNAs for HNSCC. Differentially expressed mRNAs (DEGs), miRNAs (DEMs) and lncRNAs (DELs) were identified based on the RNA sequencing data and clinical data retrieved from TCGA database. LncRNA-regulated ceRNA networks were constructed based on the interactive RNA pairs predicted by miRDB, miRcode and TargetScan. WGCNA was conducted to identify lncRNAs that were significantly correlated with patient overall survival (OS) and HNSCC tumor. RT-qPCR was employed to validate the expression of lncRNAs in HNSCC cell lines and patient sera. A ceRNA network consisting of 90 DEGs, 7 DEMs and 67 DELs associated with clinical traits was established. WGCNA and Kaplan-Meier survival analysis revealed that 5 DELs (MIR4435-2 HG, CASC9, LINC01980, STARD4-AS1 and MIR99AHG) were significantly correlated with OS of HNSCC patients, whereas DEL PART1 was most significantly correlated with the HNSCC tumor. The in silico predicted expression patterns of PART1, LINC01980 and MIR4435-2 HG were further validated in HNSCC cell lines and patient sera. Collectively, the present study provided novel insights into the lncRNA-regulated ceRNA networks in HNSCC and identified novel lncRNAs that harbor diagnostic and prognostic potentials for HNSCC.Abbreviations BP, biological process. CC, cellular component. ceRNA, competing endogenous RNA. DEG, differential expressions of mRNA. DEL, differentially expressed lncRNA. DEM, differentially expressed miRNA. ESCC, esophageal squamous cell carcinoma. FPKM, Fragments Per Kilobase Million. GO, Gene Ontology. GS, gene significance. HNSCC, head and neck squamous cell carcinoma. KEGG, Kyoto Encyclopedia of Genes and Genomes. LncRNA, long non-coding RNA. MCC, Maximal Clique Centrality. ME, module eigengenes. MF, molecular functions. MM, module membership. MRE, miRNA-binding site. MYO5A, Myosin-Va. PART1, prostate androgen-regulated transcript 1. RBM3, RNA‑binding motif protein 3. TCGA, The Cancer Genome Atlas. TOM, topological overlap measure. TSCC, tongue squamous cell carcinoma. WGCNA, weighted gene co-expression network analysis.

Long intergenic non-protein coding RNA 960 regulates cancer cell viability, migration and invasion through modulating miR-146a-5p/interleukin 1 receptor associated kinase 1 axis in pancreatic ductal adenocarcinoma

Long non-coding RNAs (lncRNAs) are considered as crucial regulatory factors in cancer biology. However, the biological function of long intergenic non-protein coding RNA 960 (LINC00960) in the tumorigenesis of pancreatic ductal adenocarcinoma (PDAC) is still unknown. The goal of this study is to investigate the role of LINC00960 in PDAC. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to examine the expression levels of LINC00960 in PDAC tissues and cell lines. After transfection, the loss-of-function models of LINC00960 or interleukin 1 receptor-associated kinase 1 (IRAK1) were established with BxPC-3 cells and Colo357 cells, and the malignant phenotypes of BxPC-3 cells and Colo357 cells were detected by CCK-8 assay, BrdU assay and Transwell assay, respectively. The interactions among LINC00960, miR-146a-5p and IRAK1 were predicted by bioinformatics analysis, and verified by luciferase reporter assay, RNA immunoprecipitation assay and RNA pull-down assay. The regulatory functions of LINC00960 and miR-146a-5p on IRAK1 were detected by Western blot. We demonstrated that the LINC00960 expression was increased in PDAC tissues and cell lines. Knocking down LINC00960 or IRAK1 could repress the viability, migration, and invasion of BxPC-3 and Colo357 cells. LINC00960 functioned as a molecular sponge for miR-146a-5p, and IRAK1 was verified as a target gene of miR-146a-5p. Additionally, LINC00960 could up-regulate IRAK1 expression via repressing miR-146a-5p, and the oncogenic properties of LINC00960 were partly reversed by miR-146a-5p. Our findings reveal that LINC00960 is a promoter of PDAC progression through regulating miR-146a-5p/IRAK1axis.

Natural products: Potential targets of TME related long non-coding RNAs in lung cancer

BACKGROUND

Lung cancer is a significant health concern worldwide due to high mortality and morbidity, despite the advances in diagnosis, treatment, and management. Recent experimental evidence from different models suggested long non-coding RNAs (lncRNAs) as major modulators of cancer stem cells (CSCs) in the tumor microenvironment (TME) to support metastasis and drug resistance in lung cancer. Evidence-based studies demonstrated that natural products interfere with TME functions.

PURPOSE OF STUDY

To establish lncRNAs of TME as novel targets of natural compounds for lung cancer management.

STUDY DESIGN

Current study used a combination of TME and lung CSCs, lncRNAs and enrichment and stemness maintenance, natural products and stem cell management, natural products and lncRNAs, natural products and targeted delivery as keywords to retrieve the literature from Scopus, Web of Science, PubMed, and Google Scholar. This study critically reviewed the current literature and presented cancer stem cells' ability in reprogramming lung TME.

RESULTS

This review found that TME related oncogenic and tumor suppressor lncRNAs and their signaling pathways control the maintenance of stemness in lung TME. This review explored natural phenolic compounds and found that curcumin, genistein, quercetin epigallocatechin gallate and ginsenoside Rh2 are efficient in managing lung CSCs. They modulate lncRNAs and their upstream mediators by targeting signaling and epigenetic pathways. This review also identified relevant nanotechnology-based phytochemical delivery approaches for targeting lung cancer.

CONCLUSION

By critical literature analysis, TME related lncRNAs were identified as potential therapeutic targets, aiming to develop natural product-based therapeutics to treat metastatic and drug-resistant lung cancers.

Overexpression of lncRNA AFAP1-AS1 as a diagnostic biomarker in non-small cell lung cancer

Background

Long non-coding RNAs (lncRNAs) play important roles in lung tumorigenesis. Among different lncRNAs, overexpression of the lncRNA actin filament‐associated protein 1‐antisense RNA 1 (AFAP1-AS1) in lung tumors has been reported in different studies. In the current study, we aimed to investigate the potential value of lncRNA AFAP1-AS1 as a diagnostic biomarker in lung cancer. Ninety samples from patients with lung cancer were collected from Noor-E-Nejat hospital, Tabriz, Iran. The expression of AFAP1-AS1 was assessed using quantitative reverse transcriptase-PCR (qRT-PCR), followed by the ROC curve analysis to investigate the biomarker potency of AFAP1-AS1.

Results

Our results revealed an upregulation of AFAP1-AS1 in tumor samples as compared to the adjacent non-tumor tissues. We found a significant positive association between AFAP1-AS1 expression and tumor size, as well as tumor stage.

Conclusions

Our results showed overexpression of AFAP1-AS1 and its capacity as a diagnostic biomarker in lung cancer.

Aberrant expression of lncRNAs SNHG6, TRPM2-AS1, MIR4435-2HG, and hypomethylation of TRPM2-AS1 promoter in colorectal cancer

Accumulating evidence has indicated that deregulation of lncRNAs plays essential roles in colorectal cancer (CRC) carcinogenesis. The goal of this study was to analyze the expression of lncRNAs in colorectal cancer and their association with clinicopathological variables. Bioinformatics analysis of published CRC microarray data was performed to identify the important lncRNAs. The expression levels of candidate genes were assessed in the human colon cancer/normal cell lines, CRC, adenomatous colorectal polyps, and their marginal tissues by qRT-PCR. Moreover, the methylation status of the TRPM2-AS1 promoter was studied using qMSP assay. Furthermore, we investigated the molecular mechanisms of these lncRNAs in CRC progression using in silico analysis. Microarray analysis revealed that lncRNAs SNHG6, MIR4435-2HG, and TRPM2-AS1 were upregulated in CRC. These results were validated in colon cell lines. Moreover, qRT-PCR showed that the expression levels of SNHG6 and TRPM2-AS1 were upregulated in the colorectal tumor tissues compared with their paired tissues. Nonetheless, there was no significant increase in MIR4435-2HG expression in CRC samples. Furthermore, we observed a significant hypomethylation of TRPM2-AS1 promoter and its activation in CRC tissues. By in silico analysis, we found that the lncRNAs upregulation could promote proliferation and drug resistance of colorectal cancer cells via miRNAs sponging and modulation of their targets expression. In conclusion, based on our results upregulation of SNHG6 and TRPM2-AS1, and hypomethylation of TRPM2-AS1 promoter might be considered as potential diagnostic biomarkers for CRC initiation and development.

A Pan-Cancer Analysis of Transcriptome and Survival Reveals Prognostic Differentially Expressed LncRNAs and Predicts Novel Drugs for Glioblastoma Multiforme Therapy

Numerous studies have identified various prognostic long non-coding RNAs (LncRNAs) in a specific cancer type, but a comprehensive pan-cancer analysis for prediction of LncRNAs that may serve as prognostic biomarkers is of great significance to be performed. Glioblastoma multiforme (GBM) is the most common and aggressive malignant adult primary brain tumor. There is an urgent need to identify novel therapies for GBM due to its poor prognosis and universal recurrence. Using available LncRNA expression data of 12 cancer types and survival data of 30 cancer types from online databases, we identified 48 differentially expressed LncRNAs in cancers as potential pan-cancer prognostic biomarkers. Two candidate LncRNAs were selected for validation in GBM. By the expression detection in GBM cell lines and survival analysis in GBM patients, we demonstrated the reliability of the list of pan-cancer prognostic LncRNAs obtained above. By constructing LncRNA-mRNA-drug network in GBM, we predicted novel drug-target interactions for GBM correlated LncRNA. This analysis has revealed common prognostic LncRNAs among cancers, which may provide insights into cancer pathogenesis and novel drug target in GBM.

LncRNA MCM3AP-AS1 sponges miR-148a to enhance cell invasion and migration in small cell lung cancer

Background

MCM3AP-AS1 is a recently characterized lncRNA playing an oncogenic role in several cancers. However, its role in lung cancer remains unknown. Here, we aimed to explore the functions of MCM3AP-AS1 in small cell lung cancer (SCLC) and the possible underlying mechanisms.

Methods

MCM3AP-AS1 and ROCK1 levels in SCLC patients were analyzed by qPCR. RNA pull-down and luciferase assays were performed to analyze the interaction between MCM3AP-AS1 and miR-148a. ROCK1 mRNA and protein levels were detected by qPCR and Western blot, respectively. Cell invasion and migration were analyzed by Transwell assays.

Results

MCM3AP-AS1 was upregulated in patients with SCLC, and a high MCM3AP-AS1 level was accompanied by a low survival rate. The binding of MCM3AP-AS1 to miR-148a predicted by bioinformatics analysis was verified by RNA pull-down and luciferase assays. However, MCM3AP-AS1 and miR-148a did not affect each other’s expression. ROCK1 was upregulated in SCLC tissues and positively correlated with MCM3AP-AS1. In SCLC cells, MCM3AP-AS1 overexpression increased ROCK1 and promoted cancer cell invasion and migration, while miR-148a overexpression showed the opposite effects and attenuated the effects of MCM3AP-AS1 overexpression on ROCK1 expression and cell behaviors.

Conclusions

MCM3AP-AS1 sponges miR-148a, thereby increasing SCLC cell invasion and migration via upregulating ROCK1 expression.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08365-8.

Long noncoding RNA MIR4435-2HG enhances metabolic function of myeloid dendritic cells from HIV-1 elite controllers

Restriction of HIV-1 replication in elite controllers (ECs) is frequently attributed to T cell-mediated immune responses, while the specific contribution of innate immune cells is less clear. Here, we demonstrate an upregulation of the host long noncoding RNA (lncRNA) MIR4435-2HG in primary myeloid dendritic cells (mDCs) from ECs. Elevated expression of this lncRNA in mDCs was associated with a distinct immunometabolic profile, characterized by increased oxidative phosphorylation and glycolysis activities in response to TLR3 stimulation. Using functional assays, we show that MIR4435-2HG directly influenced the metabolic state of mDCs, likely through epigenetic mechanisms involving H3K27ac enrichment at an intronic enhancer in the RPTOR gene locus, the main component of the mammalian target of rapamycin complex 1 (mTORC1). Together, these results suggest a role of MIR4435-2HG for enhancing immunometabolic activities of mDCs in ECs through targeted epigenetic modifications of a member of the mTOR signaling pathway.

Long Non-Coding RNA LOC648987 Promotes Proliferation and Metastasis of Renal Cell Carcinoma by Regulating Epithelial-Mesenchymal Transition

Renal cell carcinoma (RCC) is a type of urinary tumor with a high incidence and is often associated with tumor metastasis. Long non-coding RNA (lncRNA) regulates tumorigenesis, progression, and metastasis. However, the role and the predictive value of lncRNA in RCC progression and metastasis have not been elucidated. The purpose of this study was to evaluate the effect of a newly discovered lncRNA LOC648987 on RCC proliferation and metastasis. LOC648987 was identified by RT-PCR for high expression in human RCC tissues as well as in metastatic RCC tissues. In the cell experiments, we infected the RCC cell lines ACHN and 786-O cells with LOC648987-shRNA and its negative control (shNC). The results showed that the knockdown of LOC648987 inhibited the proliferation of ACHN and 786-O cells and colony formation. The cell cycle and the apoptosis progression of ACHN and 786-O cells were assessed using flow cytometry. The knockdown of LOC648987 significantly inhibited the progression of ACHN and 786-O cells from G0/G1 to S phase and promoted cell apoptosis. The metastasis promoting effects of LOC648987 on ACHN and 786-O cells were verified by transwell migration assays, which depended on vimentin and MMP-9 to regulate the epithelial-mesenchymal transition. Finally, the promotion of LOC648987 on RCC tumorigenesis was evaluated in BALb/c nude mice. These data confirmed that lncRNA LOC648987 promoted RCC cell proliferation and tumor metastasis and regulated the expression of EMT-related proteins in RCC cells.

Long non-coding RNA AWPPH enhances malignant phenotypes in nasopharyngeal carcinoma via silencing PTEN through interacting with LSD1 and EZH2

Evidence has emerged identifying long noncoding RNAs (lncRNAs) as important regulators of various cancers including nasopharyngeal carcinoma (NPC). LncRNA AWPPH is an oncogene recently identified in several cancers. However, the underlying role of AWPPH in NPC is still unclear and thus worth exploring. In this study, AWPPH expression was markedly upregulated in NPC cells. Further, loss- and gain-of-function assays indicated that AWPPH facilitates cell proliferation and migration and hinders apoptosis in NPC cells. Moreover, cytoplasmic AWPPH was predicted to share a common RNA-binding protein, IGF2BP1, with LSD1. The interaction between IGF2BP1 and both AWPPH and LSD1 mRNA was verified in NPC cells, and AWPPH stabilized LSD1 mRNA to enhance the expression of LSD1 in NPC through such interactions. Furthermore, nuclear AWPPH repressed PTEN expression through recruiting EZH2 and LSD1 to the PTEN promoter in NPC cells. Final rescue assays demonstrated that silenced PTEN could reverse the suppressive influence of AWPPH depletion on the progression of NPC. Collectively, our study shows that AWPPH inhibits PTEN expression to drive NPC progression through interacting with LSD1 and EZH2, providing potential biomarkers for NPC treatment.

Downregulation of long non-coding RNA MR4435-2HG suppresses breast cancer progression via the Wnt/β-catenin signaling pathway

Extensive research has contributed to the current understanding of the critical roles played by long non-coding RNAs in various types of cancer. The present study aimed to investigate the function and mechanism of the long non-coding RNA, MIR4435-2HG (also termed LINC00978), in breast cancer growth and metastasis. Using Gene Expression Profiling Interactive Analysis, an online web tool, it was revealed that MIR4435-2HG was upregulated in breast cancer tissue, and its high expression was associated with poor prognosis based on The Cancer Genome Atlas database. MIR4435-2HG knockdown increased cell apoptosis but decreased cell proliferation, migration and invasion. MIR4435-2HG knockdown increased pro-apoptotic protein expression but decreased anti-apoptotic protein expression. In addition, MIR4435-2HG knockdown leads to dysregulation of epithelial-to-mesenchymal transition-associated genes. Furthermore, knockdown of MIR4435-2HG results in inactivation of the Wnt/β-catenin signaling pathway. The results of the present study demonstrate the tumor-promoting role of MIR4435-2HG in breast cancer progression.

The Downregulation of Long Noncoding RNA Metastasis Associated with Colon Cancer 1 (lncRNA MACC1-AS1) Inhibits the Migration and Invasion of Non-Small Cell Lung Cancer Cells

To explore the effects of lncRNA MACC1-AS1 on the invasion and migration of non-small cell lung cancer (NSCLC), PCR was used to detect and compare lncRNA MACC1-AS1 expression in NSCLC cells to normal lung epithelial cells and assess the knockdown effect of lncRNA MACC1-AS1 in A549 and H1299 cell lines. The Transwell system was employed to compare the invasiveness of the lncRNA MACC1-AS1 knockdown cells to the control cells. The migratory ability of the lncRNA MACC1-AS1 knockdown cells was compared to the control cells via in vitro scratch assay. Western blot was used to detect the E-cadherin/N-cadherin expression. Balb/c mouse model was used to verify the metastasis ability in vivo between the control and lncRNA MACC1-AS1 knockdown groups. The level of lncRNA MACC1-AS1 was markedly higher in lung cancer cells than normal lung epithelial cells. The knockdown of lncRNA MACC1-AS1 reduced the invasiveness and migratory capacity of A549 and H1299 cells. Downregulating lncRNA MACC1-AS1 upregulated E-cadherin but down-regulated N-cadherin in A549 and H1299 cells. Besides, the silencing of lncRNA MACC1-AS1 reduced the A549 cells’ ability to metastasize in vivo. LncRNA MACC1-AS1 can enhance the invasiveness and migratory capability of NSCLC.

Crosstalk of long non-coding RNAs and EMT: Searching the missing pieces of an incomplete puzzle for lung cancer therapy

BACKGROUND

Lung cancer is considered to be the first place among the cancer-related deaths worldwide and demands novel strategies in the treatment of this life-threatening disorder. The aim of this review is to explore regulation of epithelial-to-mesenchymal transition (EMT) by long non-coding RNAs (lncRNAs) in lung cancer.

INTRODUCTION

LncRNAs can be considered as potential factors for targeting in cancer therapy, since they regulate a bunch of biological processes, e.g. cell proliferation, differentiation and apoptosis. The abnormal expression of lncRNAs occurs in different cancer cells. On the other hand, epithelial-to-mesenchymal transition (EMT) is a critical mechanism participating in migration and metastasis of cancer cells.

METHOD

Different databases including Googlescholar, Pubmed and Sciencedirect were used for collecting articles using keywords such as "LncRNA", "EMT", and "Lung cancer".

RESULT

There are tumor-suppressing lncRNAs that can suppress EMT and metastasis of lung cancer cells. Expression of such lncRNAs undergoes down-regulation in lung cancer progression and restoring their expression is of importance in suppressing lung cancer migration. There are tumor-promoting lncRNAs triggering EMT in lung cancer and enhancing their migration.

CONCLUSION

LncRNAs are potential regulators of EMT in lung cancer, and targeting them, both pharmacologically and genetically, can be of importance in controlling migration of lung cancer cells.

Upregulation of Long Non-Coding RNA GCC2-AS1 Facilitates Malignant Phenotypes and Correlated With Unfavorable Prognosis for Lung Adenocarcinoma

Background

The role played by long noncoding RNA GCC2-AS1 in primary malignant tumors remains poorly understood. This study aimed to determine the expression levels and evaluate the clinical significance and biological effects of GCC2-AS1 in lung adenocarcinoma (LUAD).

Methods

We used data obtained from tissue samples and the TCGA database to determine the levels of GCC2-AS1 expression LUAD patients, and the prognostic value of those levels. Functional experiments were performed to investigate the effect of GCC2-AS1 on LUAD cells. Genes that were differentially expressed in GCC2-AS1-low and -high groups were analyzed by an enrichment analysis. Additionally, a nomogram model was created and subgroup analyses were performed to further determine the prognostic value of GCC2-AS1 in LUAD.

Results

GCC2-AS1 expression was significantly upregulated in lung adenocarcinoma tissues as compared with normal tissues. Depletion of GCC2-AS1 inhibited the proliferation and invasion of LUAD cells in vitro. An elevated level of GCC2-AS1 was strongly correlated with shorter overall survival time and was identified as an independent prognostic marker for LUAD patients. Enrichment analyses conducted using GO, KEGG, and GSEA databases were performed to identify biological pathways that might involve GCC2-AS1. Several subgroups were found to have a significant prognostic value for patients in the GCC2-AS1-low and -high groups.

Conclusions

Our findings suggest that GCC2-AS1 can serve as a diagnostic and prognostic biomarker for LUAD patients.

Long non‑coding RNA PITPNA‑AS1 silencing suppresses proliferation, metastasis and epithelial‑mesenchymal transition in non‑small cell lung cancer cells by targeting microRNA‑32‑5p

Lung cancer is one of the most common types of cancer and has a high mortality rate, worldwide. The major histopathological subtype is non-small cell lung cancer (NSCLC). The aim of the present study was to investigate the role of long non-coding (lnc) RNA PITPNA antisense RNA 1 (PITPNA-AS1) in NSCLC and elucidate its potential mechanisms. The expression of PITPNA-AS1 was determined in several NSCLC cell lines. Following PITPNA-AS1-silencing, cell proliferation, invasion and migration were evaluated using Cell Counting Kit-8, colony formation, Transwell assay and wound healing assays, respectively. The expression levels of proliferation-, migration- and epithelial-mesenchymal transition (EMT)-associated proteins were examined using immunofluorescence assay or western blot analysis. A luciferase reporter assay was conducted to verify the potential interaction between PITPNA-AS1 and microRNA(miR)-32-5p. Subsequently, rescue assays were performed to investigate the effects of PITPNA-AS1 and miR-32-5p on NSCLC progression. The results demonstrated that PITPNA-AS1 was highly expressed in NSCLC tissues and cell lines. It was found that PITPNA-AS1 silencing inhibited the proliferation, invasion and migration of NSCLC cells. Furthermore, the protein expression of E-cadherin was upregulated, while the expression levels N-cadherin and vimentin were downregulated. The luciferase reporter assay confirmed that miR-32-5p was a direct target of PITPNA-AS1. The rescue experiments suggested that a miR-32-5p inhibitor significantly reversed the inhibitory effects of PITPNA-AS1 silencing on proliferation, invasion, migration and EMT in NSCLC cells. Collectively, the present results demonstrated that PITPNA-AS1 silencing could suppress the progression of NSCLC by targeting miR-32-5p, suggesting a promising biomarker in NSCLC diagnosis and treatment.

LncRNA MIR4435-2HG mediates cisplatin resistance in HCT116 cells by regulating Nrf2 and HO-1

PURPOSE

Cisplatin resistance is still a serious problem in the clinic. However, the underlying mechanism remains unknown. In our study, we investigated cisplatin resistance by using the cisplatin-resistant cell line HCT116R.

METHODS

The HCT116 cell line, a colon cancer cell line, was purchased. Cell viability was determined using CCK-8 Assay Kit. The gene expression levels of MIR4435-2HG, Nrf2, and HO-1, and caspase activity were determined using qRT-PCR and Caspase 3 Assay Kit, respectively.

RESULTS

In this study, we found that the levels of the lncRNA MIR4435-2HG were dramatically increased in the cisplatin-resistant cell line HCT116R. Knockdown of MIR4435-2HG in HCT116R cells significantly restored the sensitivity to cisplatin, inhibited cell proliferation and promoted cell apoptosis. Furthermore, Nrf2 and HO-1 mRNA levels, as critical molecules in the oxidative stress pathway, were inhibited by siRNAs targeting MIR4435-2HG, suggesting that MIR4435-2HG-mediated cisplatin resistance occurs through the Nrf2/HO-1 pathway.

CONCLUSION

Our findings demonstrate that the lncRNA MIR4435-2HG is a main factor driving the cisplatin resistance of HCT116 cells.

Identification of a nomogram based on an 8-lncRNA signature as a novel diagnostic biomarker for head and neck squamous cell carcinoma

Long noncoding RNAs (lncRNAs) have been proposed as diagnostic or prognostic biomarkers of head and neck squamous carcinoma (HNSCC). The current study aimed to develop a lncRNA-based prognostic nomogram for HNSCC. LncRNA expression profiles were downloaded from The Cancer Genome Atlas (TCGA) database. After the reannotation of lncRNAs, the differential analysis identified 253 significantly differentially expressed lncRNAs in training set TCGA-HNSC (n = 300). The prognostic value of each lncRNA was first estimated in univariate Cox analysis, and 41 lncRNAs with P < 0.05 were selected as seed lncRNAs for Cox LASSO regression, which identified 11 lncRNAs. Multivariate Cox analysis was used to establish an 8-lncRNA signature with prognostic value. Patients in the high-signature score group exhibited a significantly worse overall survival (OS) than those in the low-signature score group, and the area under the receiver operating characteristic (ROC) curve for 3-year survival was 0.74. Multivariable Cox regression analysis among the clinical characteristics and signature scores suggested that the signature is an independent prognostic factor. The internal validation cohort, external validation cohort, and 102 HNSCC specimens quantified by qRT-PCR successfully validate the robustness of our nomogram.

LncRNA GATA6-AS1 Inhibits the Progression of Non-Small Cell Lung Cancer via Repressing microRNA-543 to Up-Regulating RKIP

Background

Much evidence unveils the significance of long non-coding RNAs (lncRNAs) in diverse cancers. This study was designed to clarify the function and mechanism of lncRNA GATA6 antisense RNA 1 (GATA6-AS1) in the progression of non-small cell lung cancer (NSCLC).

Methods

GATA6-AS1, miR-543 and Raf kinase inhibitor protein (RKIP) mRNA expressions were detected by qRT-PCR. Chi-square test was adopted to analyze the relationship between GATA6-AS1 expression and the clinicopathological parameters of NSCLC patients. NSCLC cells H1299 and H460 cells were used as overexpression or knockdown models, respectively, and cell proliferation and metastasis were determined by CCK-8 and Transwell assays. RKIP, E-cadherin, N-cadherin, STAT3, p-STAT3 expressions in NSCLC cells were detected by Western blot. The targeting relationship between GATA6-AS1 and miR-543 was confirmed by dual-luciferase reporter assay.

Results

GATA6-AS1 was significantly lowly expressed in NSCLC tissues and cell lines, and its low expression level was significantly correlated with larger tumor size and positive lymph node metastasis. GATA6-AS1 overexpression inhibited the proliferation, migration, invasion and epithelial–mesenchymal transition of NSCLC cells, while GATA6-AS1 knockdown caused the opposite effects. Mechanistically, it was confirmed that GATA6-AS1 impeded NSCLC cell proliferation and metastasis by adsorbing miR-543 and up-regulating the expression of RKIP.

Conclusions

As a tumor suppressor, GATA6-AS1 participates in suppressing the progression of NSCLC by modulating the miR-543/RKIP axis.

Knockdown of MIR4435-2HG Suppresses the Proliferation, Migration and Invasion of Cervical Cancer Cells via Regulating the miR-128-3p/MSI2 Axis in vitro

PURPOSE

Long non-coding RNAs (lncRNAs) play major roles in the development of several cancers, including cervical cancer (CC). The purpose of the present study is to explore the regulatory mechanism of MIR4435-2HG on CC in vitro.

PATIENTS AND METHODS

Fifty-nine pairs of CC tissues and adjacent normal tissues were collected from 59 patients by resection. The expression of lncRNA MIR4435-2HG, microRNA (miR)-128-3p and Musashi 2 (MSI2) in CC tissues and cells was detected by quantitative reverse-transcription PCR (qRT-PCR). The viability of CC cells was detected by 3-(4, 5-Dimethyl-2-Thiazolyl)-2, 5-Diphenyl-2-H-Tetrazolium Bromide (MTT) assay. The ability of migration and invasion in CC cells was measured by wound healing assay and transwell invasion assay, respectively. Starbase software and Targetscan software were utilized to predict the relationship between miR-128 and MIR4435-2HG/MSI2, respectively. The dual-luciferase reporter assay was used to confirm these interactions.

RESULTS

LncRNA MIR4435-2HG expression was significantly up-regulated in CC tissues (P < 0.001) and cells (P < 0.01). Knockdown of MIR4435-2HG inhibited the proliferation, migration and invasion of CC cells (P < 0.01). MiR-128-3p was a target of MIR4435-2HG and was negatively modulated by MIR4435-2HG (P < 0.0001, r = -0.6331). Up-regulation of miR-128-3p suppressed the proliferation, migration and invasion of CC cells (P < 0.01). In addition, MSI2 was the target gene of miR-128-3p and negatively regulated by miR-128-3p (P < 0.0001, r = -0.4775). Both down-regulation of miR-128-3p and up-regulation of MSI2 reversed the inhibitory effects of MIR4435-2HG knockdown on the proliferation, migration and invasion of CC cells (P < 0.05).

CONCLUSION

MIR4435-2HG knockdown suppresses the proliferation, migration and invasion of CC cells through regulating the miR-128-3p/MSI2 axis, providing a possible therapeutic strategy for CC.

One locus with two roles: microRNA-independent functions of microRNA-host-gene locus-encoded long noncoding RNAs

Long noncoding RNAs (lncRNAs) are RNA transcripts longer than 200 nucleotides that do not code for proteins. LncRNAs play crucial regulatory roles in several biological processes via diverse mechanisms and their aberrant expression is associated with various diseases. LncRNA genes are further subcategorized based on their relative organization in the genome. MicroRNA (miRNA)-host-gene-derived lncRNAs (lnc-MIRHGs) refer to lncRNAs whose genes also harbor miRNAs. There exists crosstalk between the processing of lnc-MIRHGs and the biogenesis of the encoded miRNAs. Although the functions of the encoded miRNAs are usually well understood, whether those lnc-MIRHGs play independent functions are not fully elucidated. Here, we review our current understanding of lnc-MIRHGs, including their biogenesis, function, and mechanism of action, with a focus on discussing the miRNA-independent functions of lnc-MIRHGs, including their involvement in cancer. Our current understanding of lnc-MIRHGs strongly indicates that this class of lncRNAs could play important roles in basic cellular events as well as in diseases. This article is categorized under: Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs Regulatory RNAs/RNAi/Riboswitches > Biogenesis of Effector Small RNAs.

CLPTM1L induces estrogen receptor β signaling-mediated radioresistance in non-small cell lung cancer cells

INTRODUCTION

Radioresistance is a major challenge in lung cancer radiotherapy, and new radiosensitizers are urgently needed. Estrogen receptor β (ERβ) is involved in the progression of non-small cell lung cancer (NSCLC), however, the role of ERβ in the response to radiotherapy in lung cancer remains elusive. In the present study, we investigated the mechanism underlying ERβ-mediated transcriptional activation and radioresistance of NSCLC cells.

METHODS

Quantitative real-time PCR, western blot and immunohistochemistry were used to detect the expression of CLPTM1L, ERβ and other target genes. The mechanism of CLPTM1L in modulation of radiosensitivity was investigated by chromatin immunoprecipitation assay, luciferase reporter gene assay, immunofluorescence staining, confocal microscopy, coimmunoprecipitation and GST pull-down assays. The functional role of CLPTM1L was detected by function assays in vitro and in vivo.

RESULTS

CLPTM1L expression was negatively correlated with the radiosensitivity of NSCLC cell lines, and irradiation upregulated CLPTM1L in radioresistant (A549) but not in radiosensitive (H460) NSCLC cells. Meanwhile, IR induced the translocation of CLPTM1L from the cytoplasm into the nucleus in NSCLC cells. Moreover, CLPTM1L induced radioresistance in NSCLC cells. iTRAQ-based analysis and cDNA microarray identified irradiation-related genes commonly targeted by CLPTM1L and ERβ, and CLPTM1L upregulated ERβ-induced genes CDC25A, c-Jun, and BCL2. Mechanistically, CLPTM1L coactivated ERβ by directly interacting with ERβ through the LXXLL NR (nuclear receptor)-binding motif. Functionally, ERβ silencing was sufficient to block CLPTM1L-enhanced radioresistance of NSCLC cells in vitro. CLPTM1L shRNA treatment in combination with irradiation significantly inhibited cancer cell growth in NSCLC xenograft tumors in vivo.

CONCLUSIONS

The present results indicate that CLPTM1L acts as a critical coactivator of ERβ to promote the transcription of its target genes and induce radioresistance of NSCLC cells, suggesting a new target for radiosensitization in NSCLC therapy. Video Abstract.

lncRNA MIR4435-2HG promoted clear cell renal cell carcinoma malignant progression via miR-513a-5p/KLF6 axis

Long non-coding RNAs (lncRNAs) take various biological effects in clear cell renal cell carcinoma (ccRCC) mostly through sponging with microRNAs (miRNAs). lncRNA MIR4435-2HG is found to promote tumour progression in gastric cancer, glioblastoma and hepatocellular carcinoma. However, the role of lncRNA MIR4435-2HG in ccRCC progression remains unknown. The purpose of this research was to investigate the potential molecular mechanism of lncRNA MIR4435-2HG regarding the regulation of ccRCC initiation and progression. In this study, we found the up-regulation of MIR4435-2HG in ccRCC tissues and cell lines. Functionally, overexpression of MIR4435-2HG promoted the proliferation as well as the metastasis in ccRCC cell lines, whereas knockdown of MIR4435-2HG inhibited the above changes. Then, bioinformatic analysis and luciferase reporter assays confirmed the negative regulation effect of MIR4435-2HG on miR-513a-5p. And further investigations showed that KLF6, which collected from the intersection of databases, was the potential conjugated mRNAs of miR-513a-5p. Finally, the rescue experiments revealed the relation among MIR4435-2HG and KLF6, which showed that KLF6 could reverse the promoting effect of MIR4435-2HG on ccRCC in vitro and in vivo. Therefore, our findings provided insight into the mechanisms of MIR4435-2HG in ccRCC and revealed an alternative target for the clinical diagnosis and treatment of ccRCC.

Fifteen mRNA-lncRNA expression-based signature predicted the survival of late-staged head and neck squamous cell carcinoma

Background: Gene expression is necessary for regulation in almost all biological processes, at the same time, it is related to the prognosis for head and neck squamous cell carcinoma (HNSCC). The prognosis of late-staged HNSCC is important because of its guiding significance on the therapy strategies.

Methods: In this work, we analyzed the relationship between gene expression and HNSCC in The Cancer Genome Atlas (TCGA) cohort, and optimized the panel with random forest survival analysis. Subsequently, a Cox multivariate regression-based model was developed to predict the clinical outcome of HNSCC. The performance of the model was assayed in the training cohort and validated in another three independent cohorts (GSE41614, E-TABM-302, E-MTAB-1328). The underlying pathways significantly associated with the model were identified. According to the results, patients of low-score group (median survival months: 27.4, 95% CI: 18.2–43) had a significant poor survival than those of high-score group (median survival months: 69.4, 95% CI: 58.7–72.1, P=2.7e-5), and the observation was repeatable in the other validation cohorts. Further analysis revealed that the model performed better than the other clinical indicators and is independent of these indicators.

Results: Comparison revealed that the model performed better than existing models for late HNSCC prognosis. Gene set enrichment analysis (GSEA) elucidated that the model was significantly associated with various cell processes and pathways.

Roles of Wnt/β-Catenin Signaling Pathway Regulatory Long Non-Coding RNAs in the Pathogenesis of Non-Small Cell Lung Cancer

Lung cancer is one of the leading causes of cancer-related mortality worldwide. Non-small cell lung cancer (NSCLC) is the most common pathological type of lung cancer. Long non-coding RNAs (lncRNAs) are promising novel diagnostic and prognostic biomarkers, as well as potential therapeutic targets for lung cancer. Long non-coding RNAs (lncRNAs) have been demonstrated to modulate tumor cells proliferation, cell cycle progression, invasion, and metastasis by regulating gene expression at transcriptional, post-transcriptional, and epigenetic levels. The oncogenic aberrant Wnt/β-catenin signaling is prominent in lung cancer, playing a vital role in tumorigenesis, prognosis, and resistance to therapy. Interestingly, compelling studies have demonstrated that lncRNAs exert either oncogenic or tumor suppressor roles by regulating Wnt/β-catenin signaling. In this review, we aim to present the current accumulated knowledge regarding the roles of Wnt/β-catenin signaling-regulated lncRNAs in the pathogenesis of non-small cell lung cancer (NSCLC). Better understanding of the effects of lncRNAs on Wnt/β-catenin signaling might contribute to the improved understanding of the molecular tumor pathogenesis and to the uncovering of novel therapeutic targets in NSCLC.

LncRNA MIR4435-2HG potentiates the proliferation and invasion of glioblastoma cells via modulating miR-1224-5p/TGFBR2 axis

Glioblastoma (GBM) belongs to the high-grade (IV) gliomas with extremely poor prognosis. Accumulating evidence uncovered the key roles of long non-coding RNAs (lncRNAs) in GBM development. This study aimed to determine the biological actions and the clinical relevance of lncRNA MIR4435-2 Host Gene (MIR4435-2HG) in GBM. Data from GEPIA database showed that MIR4435-2HG was up-regulated in GBM tissues and high expression of MIR4435-2HG correlated with shorter overall survival of GBM patients. Further experimental assays verified the up-regulation of MIR4435-2HG in GBM tissues and cell lines. In vitro cell studies and in vivo animal studies showed that knockdown of MIR4435-2HG resulted in the inhibition of GBM cell proliferation and invasion and in vivo tumour growth, while MIR4435-2HG overexpression driven GBM progression. Furthermore, MIR44435-2HG was found to sponge miR-1224-5p and suppress miR-1224-5p expression; overexpression of miR-1224-5p attenuated the enhancement in GBM cell proliferation and invasion induced by MIR4435-2HG overexpression. In a subsequent study, miR-1224-5p was found to target transforming growth factor-beta receptor type 2 (TGFBR2) and repressed TGFBR2 expression, and in vitro assays showed that miR-1224-5p exerted tumour-suppressive effects via targeting TGFBR2. More importantly, TGFRB2 knockdown antagonized hyper-proliferation and invasion of GBM cells with MIR4435-2HG overexpression. Clinically, the down-regulation of miR-1224-5p and up-regulation of TGFBR2 were verified in the GBM clinical samples. Taken together, the present study suggests the oncogenic role of MIR4435-2HG in GBM and underlies the key function of MIR4435-2HG-driven GBM progression via targeting miR-1224-5p/TGFBR2 axis.

LncRNA MIR4435-2HG-mediated upregulation of TGF-β1 promotes migration and proliferation of nonsmall cell lung cancer cells

The roles of long noncoding RNAs (lncRNAs) have been shown to play critical roles in tumor progression. Here, it was identified that lncRNA MIR4435-2HG was highly expressed in lung cancer tissues, especially in nonsmall cell lung cancer (NSCLC). A consistent result was obtained in lung cancer cells. Functional experiments showed that knockdown of MIR4435-2HG reduced the proliferation and migration ability of NSCLC cells. Transcriptome-sequencing analysis indicated that TGF-β signaling was mostly enriched in NSCLC cells with MIR4435-2HG knockdown. Furthermore, MIR4435-2HG was identified as an miRNA sponge for TGF-β1 and thus activated TGF-β signaling. Additionally, re-activation of TGF-β1 rescued MIR4435-2HG knockdown-mediated inhibition on the progression of NSCLC cells. Therefore, this work indicates a novel MIR4435-2HG/TGF-β1 axis responsible for NSCLC cell progression.

LncRNA MIR4435-2HG triggers ovarian cancer progression by regulating miR-128-3p/CKD14 axis

Background

Accumulating studies showed that long noncoding RNAs (lncRNAs) played vital roles in cancer progression. LncRNA MIR4435-2HG was proved to act as an oncogene in various tumors. However, the underlying function of MIR4435-2HG in ovarian cancer (OC) remains unclear.

Methods

The expression levels of MIR4435-2HG, miR-128-3p and cyclin-dependent kinase 14 (CDK14) were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation and apoptosis in OC cells were detected by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and flow cytometric analysis, respectively. Transwell assay was applied to evaluate cell migration and invasion. Wound healing assay was performed to monitor the migration rate. Western blot assay was performed to detect the protein levels of Bcl-2, Cleaved PARP, E-cadherin, Vimentin and CDK14 in OC cells. The binding sites between miR-128-3p and MIR4435-2HG or CDK14 were predicted by online tool starBase and their relationship was confirmed by dual-luciferase reporter assay, RIP assay and pull-down experiment.

Results

MIR4435-2HG and CDK14 were over-expressed in OC tissues and cells. Patients with high MIR4435-2HG expression had poorer overall survival (OS) than patients with low MIR4435-2HG expression. MIR4435-2HG knockdown inhibited proliferation, invasion and migration but induced apoptosis of OC cells via miR-128-3p/CDK14 axis. In conclusion, MIR4435-2HG knockdown suppressed the progression of OC cells through downregulating CDK14 expression by the promotion of miR-128-3p.