Identification of novel LncRNA targeting Smad2/PKCα signal pathway to negatively regulate malignant progression of glioblastoma

High expression of COPZ2 is associated with poor prognosis and cancer progression in glioma

Background

Coatomer protein complex zeta 2 (COPZ2) is a member of heptameric coatomer protein complex I and has been reported to be involved in various tumors. However, COPZ2's potential involvement in glioma remains to be explored.

Methods

The COPZ2 expression and related clinical data were obtained from The Cancer Genome Atlas (TCGA). TIMER2.0 and the Ualcan database were utilized to assess the COPZ2 expression in various tumors. Univariable, multivariate Cox regression, Kaplan-Meier methods, nomogram analysis, and ROC curve analysis were carried out to assess the relationship of COPZ2 and other prognostic factors with glioma. The LinkedOmics database was used to predict the potential biological mechanism of COPZ2 in glioma. We also conducted in vitro experiments to evaluate the functional role and mechanism of COPZ2 in glioma cell lines.

Results

We found that COPZ2 was highly expressed in glioma and it was associated with age and WHO grades. Kaplan-Meier survival curves, Cox analysis, nomogram analysis, and ROC curve showed that COPZ2 was a disadvantageous factor in poor glioma prognosis. The functions of COPZ2 and co-expression genes were significantly associated with neutrophil-mediated immunity, granulocyte activation, and response to interferon-gamma. In addition, COPZ2 knockdown significantly inhibited the proliferation, migration, and invasion of glioblastoma cells. Mechanistically, COPZ2 suppressed tumor development by participating in the regulation of the PI3K-AKT signaling pathway.

Conclusion

Our results demonstrated that the elevation of COPZ2 was associated with the prognosis and progression of glioma, and it might be a potential diagnostic and prognostic biomarker for glioma.

Role of Non-Coding RNAs in TGF-β Signalling in Glioma

Brain tumours and Gliomas, in particular, are among the primary causes of cancer mortality worldwide. Glioma diagnosis and therapy have not significantly improved despite decades of efforts. Autocrine TGF-β signalling promotes glioma proliferation, invasion, epithelial-to-mesenchymal transition (EMT), and drug resistance. Non-coding RNAs such as miRNA, lncRNA, and circRNAs have emerged as critical transcriptional and post-transcriptional regulators of TGF-β pathway components in glioma. Here, we summarize the complex regulatory network among regulatory ncRNAs and TGF-β pathway during Glioma pathogenesis and discuss their role as potential therapeutic targets for Gliomas.

Regulation of EMT Markers, Extracellular Matrix, and Associated Signalling Pathways by Long Non-Coding RNAs in Glioblastoma Mesenchymal Transition: A Scoping Review

Glioblastoma (GBM) mesenchymal (MES) transition can be regulated by long non-coding RNAs (lncRNAs) via modulation of various factors (Epithelial-to-Mesenchymal (EMT) markers, biological signalling, and the extracellular matrix (ECM)). However, understanding of these mechanisms in terms of lncRNAs is largely sparse. This review systematically analysed the mechanisms by which lncRNAs influence MES transition in GBM from a systematic search of the literature (using PRISMA) performed in five databases (PubMed, MEDLINE, EMBASE, Scopus, and Web of Science). We identified a total of 62 lncRNAs affiliated with GBM MES transition, of which 52 were upregulated and 10 were downregulated in GBM cells, where 55 lncRNAs were identified to regulate classical EMT markers in GBM (E-cadherin, N-cadherin, and vimentin) and 25 lncRNAs were reported to regulate EMT transcription factors (ZEB1, Snai1, Slug, Twist, and Notch); a total of 16 lncRNAs were found to regulate the associated signalling pathways (Wnt/β-catenin, PI3k/Akt/mTOR, TGFβ, and NF-κB) and 14 lncRNAs were reported to regulate ECM components (MMP2/9, fibronectin, CD44, and integrin-β1). A total of 25 lncRNAs were found dysregulated in clinical samples (TCGA vs. GTEx), of which 17 were upregulated and 8 were downregulated. Gene set enrichment analysis predicted the functions of HOXAS3, H19, HOTTIP, MEG3, DGCR5, and XIST at the transcriptional and translational levels based on their interacting target proteins. Our analysis observed that the MES transition is regulated by complex interplays between the signalling pathways and EMT factors. Nevertheless, further empirical studies are required to elucidate the complexity in this process between these EMT factors and the signalling involved in the GBM MES transition.

Protein Kinase C (PKC) Isozymes as Diagnostic and Prognostic Biomarkers and Therapeutic Targets for Cancer

Protein kinase C (PKC) is a large family of calcium- and phospholipid-dependent serine/threonine kinases that consists of at least 11 isozymes. Based on their structural characteristics and mode of activation, the PKC family is classified into three subfamilies: conventional or classic (cPKCs; α, βI, βII, and γ), novel or non-classic (nPKCs; δ, ε, η, and θ), and atypical (aPKCs; ζ, ι, and λ) (PKCλ is the mouse homolog of PKCι) PKC isozymes. PKC isozymes play important roles in proliferation, differentiation, survival, migration, invasion, apoptosis, and anticancer drug resistance in cancer cells. Several studies have shown a positive relationship between PKC isozymes and poor disease-free survival, poor survival following anticancer drug treatment, and increased recurrence. Furthermore, a higher level of PKC activation has been reported in cancer tissues compared to that in normal tissues. These data suggest that PKC isozymes represent potential diagnostic and prognostic biomarkers and therapeutic targets for cancer. This review summarizes the current knowledge and discusses the potential of PKC isozymes as biomarkers in the diagnosis, prognosis, and treatment of cancers.

Function of the Long Noncoding RNAs in Hepatocellular Carcinoma: Classification, Molecular Mechanisms, and Significant Therapeutic Potentials

Hepatocellular carcinoma (HCC) is the most common and serious type of primary liver cancer. HCC patients have a high death rate and poor prognosis due to the lack of clear signs and inadequate treatment interventions. However, the molecular pathways that underpin HCC pathogenesis remain unclear. Long non-coding RNAs (lncRNAs), a new type of RNAs, have been found to play important roles in HCC. LncRNAs have the ability to influence gene expression and protein activity. Dysregulation of lncRNAs has been linked to a growing number of liver disorders, including HCC. As a result, improved understanding of lncRNAs could lead to new insights into HCC etiology, as well as new approaches for the early detection and treatment of HCC. The latest results with respect to the role of lncRNAs in controlling multiple pathways of HCC were summarized in this study. The processes by which lncRNAs influence HCC advancement by interacting with chromatin, RNAs, and proteins at the epigenetic, transcriptional, and post-transcriptional levels were examined. This critical review also highlights recent breakthroughs in lncRNA signaling pathways in HCC progression, shedding light on the potential applications of lncRNAs for HCC diagnosis and therapy.

Crosstalk between PI3K/AKT/mTOR and WNT/β-Catenin signaling in GBM - Could combination therapy checkmate the collusion?

Glioblastoma multiforme is one of the calamitous primary glial brain tumors with extensive heterogeneity at cellular and molecular levels. While maximal surgical resection trailed by radio and chemotherapy employing temozolomide remains the gold-standard treatment for malignant glioma patients, the overall prognosis remains dismal and there exists an unmet need for effective therapeutic strategies. In this context, we hypothesize that proper understanding of signaling pathways responsible for glioblastoma multiforme proliferation would be the first trump card while searching for novel targeted therapies. Among the pathways aberrantly activated, PI3K/AKT/mTOR is the most significant pathway, that is clinically implicated in malignancies such as high-grade glioma. Further, the WNT/β-Catenin cascade is well-implicated in several malignancies, while its role in regulating glioma pathogenesis has only emerged recently. Nevertheless, oncogenic activation of both these pathways is a frequent event in malignant glioma that facilitates tumor proliferation, stemness and chemo-resistance. Recently, it has been reported that the cross-talk of PI3K/AKT/mTOR pathway with multiple signaling pathways could promote glioma progression and reduce the sensitivity of glioma cells to the standard therapy. However, very few studies had focused on the relationship between PI3K/AKT/mTOR and WNT/β-Catenin pathways in glioblastoma multiforme. Interestingly, in homeostatic and pathologic circumstances, both these pathways depict fine modulation and are connected at multiple levels by upstream and downstream effectors. Thus, gaining deep insights on the collusion between these pathways would help in discovering unique therapeutic targets for glioblastoma multiforme management. Hence, the current review aims to address, "the importance of inter-play between PI3K/AKT/mTOR and WNT/β-Catenin pathways", and put forward, "the possibility of combinatorially targeting them", for glioblastoma multiforme treatment enhancement.

LncRNA MEG3 alleviates PFOS induced placental cell growth inhibition through its derived miR-770 targeting PTX3

Perfluorooctane sulfonic acid (PFOS) is a persistent environmental pollutant. Exposure to PFOS has been associated with abnormal fetal development. The long non-coding RNA (lncRNA) has been showed to play a role in fetal growth restriction (FGR), preeclampsia (PE) and other pregnancy complications. Whether the lncRNA contributes to PFOS-induced toxicity in the placenta remains unknown. In this study, we investigated the function of lncRNA MEG3 and its derived miR-770 in PFOS-induced placental toxicity. Pregnant mice received gavage administration of different concentrations of PFOS (0.5, 2.5, and 12.5 mg/kg/day) from GD0 to GD17, and HTR-8/SVneo cells were treated with PFOS in the concentrations of 0, 10^-1, 1, 10 μM. We found that expression levels of miR-770 and its host gene MEG3 were reduced in mice placentas and HTR-8/SVneo cells with exposure of PFOS. A significant hypermethylation was observed at MEG3 promoter in placentas of mice gestational-treated with PFOS. We also confirmed that MEG3 and miR-770 overexpression alleviated the cell growth inhibition induced by PFOS. Furthermore, PTX3 (Pentraxin 3) was identified as the direct target of miR-770 and it was enhanced after PFOS exposure. In summary, our results suggested that MEG3 alleviate PFOS-induced placental cell inhibition through MEG3/miR-770/PTX3 axis.

lncRNA HIF1A-AS2: A potential oncogene in human cancers (Review)

Long non-coding RNAs (lncRNAs) are transcripts that are >200 nucleotides, but with no open reading frame. An increasing number of lncRNAs have been identified following the development of second-generation sequencing technologies, and they have since become a research hotspot. Functionally, they play a vital role in tumor progression, including in tumor proliferation, migration, invasion, apoptosis and acquisition of drug resistance. They regulate gene expression primarily through interaction with DNA, RNA and proteins at the epigenetic, transcriptional and post-transcriptional levels. Endogenous hypoxia-inducible factor 1α antisense RNA 2 (lncRNA HIF1A-AS2) is aberrantly expressed and involved the development/progression of various types of tumors, such as bladder cancer, glioblastoma, breast cancer and osteosarcoma. It plays a vital role in the proliferation, apoptosis, migration, invasion and epithelial-mesenchymal transformation of various tumor cells. This review summarizes the current body of knowledge on the biological functions and related molecular mechanisms of lncRNA HIF1A-AS2 in the development/progression of human tumors and other diseases.

Roles of Long Noncoding RNAs in Conferring Glioma Progression and Treatment

Accompanying the development of biomedicine, our knowledge of glioma, one of the most common primary intracranial carcinomas, is becoming more comprehensive. Unfortunately, patients with glioblastoma (GBM) still have a dismal prognosis and a high relapse rate, even with standard combination therapy, namely, surgical resection, postoperative radiotherapy and chemotherapy. The absence of validated biomarkers is responsible for the majority of these poor outcomes, and reliable therapeutic targets are indispensable for improving the prognosis of patients suffering from gliomas. Identification of both precise diagnostic and accurate prognostic markers and promising therapeutic targets has therefore attracted considerable attention from researchers. Encouragingly, accumulating evidence has demonstrated that long noncoding RNAs (lncRNAs) play important roles in the pathogenesis and oncogenesis of various categories of human tumors, including gliomas. Nevertheless, the underlying mechanisms by which lncRNAs regulate diverse biological behaviors of glioma cells, such as proliferation, invasion and migration, remain poorly understood. Consequently, this review builds on previous studies to further summarize the progress in the field of lncRNA regulation of gliomas over recent years and addresses the potential of lncRNAs as diagnostic and prognostic markers and therapeutic targets.

The complexities of PKCα signaling in cancer

Protein kinase C α (PKCα) is a ubiquitously expressed member of the PKC family of serine/threonine kinases with diverse functions in normal and neoplastic cells. Early studies identified anti-proliferative and differentiation-inducing functions for PKCα in some normal tissues (e.g., regenerating epithelia) and pro-proliferative effects in others (e.g., cells of the hematopoietic system, smooth muscle cells). Additional well documented roles of PKCα signaling in normal cells include regulation of the cytoskeleton, cell adhesion, and cell migration, and PKCα can function as a survival factor in many contexts. While a majority of tumors lose expression of PKCα, others display aberrant overexpression of the enzyme. Cancer-related mutations in PKCα are uncommon, but rare examples of driver mutations have been detected in certain cancer types (e. g., choroid gliomas). Here we review the role of PKCα in various cancers, describe mechanisms by which PKCα affects cancer-related cell functions, and discuss how the diverse functions of PKCα contribute to tumor suppressive and tumor promoting activities of the enzyme. We end the discussion by addressing mutations and expression of PKCα in tumors and the clinical relevance of these findings.

The transcription factor USF1 promotes glioma cell invasion and migration by activating lncRNA HAS2-AS1

Objective: The role of lncRNAs in tumor has been widely concerned. The present study took HAS2-AS1 (the antisense RNA 1 of HAS2) as a starting point to explore its expression in glioma and its role in the process of migration and invasion, providing a strong theoretical basis for mining potential therapeutic targets of glioma.

Methods: Clinical data of glioma were obtained from The Cancer Genome Atlas (TCGA) database and differentially expressed lncRNAs were analyzed by edgeR. The hTFtarget database was used to predict the upstream transcription factors of HAS2-AS1 and the JASPAR website was used to predict the binding sites of human upstream transcription factor 1 (USF1) and HAS2-AS1. qRT-PCR was used to detect the expressions of HAS2-AS1 and USF1 in glioma tissues and cell lines. The effects of silencing HAS2-AS1 on the migration and invasion of cancer cells were verified by wound healing and Transwell invasion assays. The chromatin immunoprecipitation (ChIP) and dual luciferase reporter assays were applied to demonstrate the binding of USF1 and HAS2-AS1 promoter region. Western blot was used to detect the expressions of epithelial–mesenchymal transition (EMT)-related proteins.

Results: HAS2-AS1 was highly expressed in glioma tissues and cells, and was significantly associated with poor prognosis. Silencing HAS2-AS1 expression inhibited glioma cell migration, invasion and EMT. USF1 was highly expressed in glioma and positively correlated with HAS2-AS1. The transcription of HAS2-AS1 was activated by USF1 via binding to HAS2-AS1 promoter region, consequently potentiating the invasion and migration abilities of glioma cells.

Conclusion: These results suggested that the transcription factor USF1 induced up-regulation of lncRNA HAS2-AS1 and promoted glioma cell invasion and migration.

Enhancer II-targeted dsRNA decreases GDNF expression via histone H3K9 trimethylation to inhibit glioblastoma progression

BACKGROUND

Glial cell line-derived neurotrophic factor (GDNF) is expressed in both astrocytes and glioblastoma (GBM) cells. GDNF expression is significantly increased in GBM, and inhibiting its expression can retard GBM progression. However, there is no known method for specific inhibition of GDNF in GBM cells.

METHODS

Promoter-targeted dsRNA-induced transcriptional gene silencing or activation was recently achieved in human cells. This approach has the potential to specifically regulate gene transcription via epigenetic modifications. In this study, we designed six candidate dsRNAs targeting the enhancer or silencer in GDNF gene promoter II to check their effects on GDNF transcription and GBM progression.

RESULTS

Among these dsRNAs, enhancer II-targeted dsRNA significantly inhibited U251 GBM progression by downregulating GDNF (P < 0.05), while silencer II-targeted dsRNA exerted an opposite effect. Moreover, enhancer II-targeted dsRNA did not significantly change GDNF expression in human astrocytes (HA) and the proliferation and migration of HA cells (P > 0.05). Bisulfate PCR and chromatin immunoprecipitation analyses revealed that both DNA methylation and trimethylation of histone 3 at lysine 9 (H3K9me3) at silencer II-targeted region significantly increased, and H3K9me3 at enhancer II-targeted region significantly decreased, in U251 cells compared with HA cells in non-intervention condition (P < 0.05). Both enhancer II- and silencer II-targeted dsRNA significantly increased H3K9me3 methylation rather than DNA at the targeted site in U251 cells (P < 0.05). The expression and activity of histone methyltransferase SETDB1 increased dramatically in U251 cells compared with HA cells, and it was recruited to enhancer II targeting region after enhancer II-targeted dsRNA treatment in U251 cells (P < 0.05).

CONCLUSIONS

Our results demonstrate that a promoter-targeted dsRNA can silence or promote gene transcription depending on its targeted site in different cis-acting elements in the gene promoter. Targeted inhibition of GDNF by enhancer II-targeted dsRNA may be explored as a novel treatment for GBM.

The PKC universe keeps expanding: From cancer initiation to metastasis

Classical and novel protein kinase C (PKC) isozymes (c/nPKCs), members of the PKC family that become activated by the lipid second messenger diacylglycerol (DAG) and phorbol esters, exert a myriad of cellular effects that impact proliferative and motile cellular responses. While c/nPKCs have been indisputably associated with tumor promotion, their roles exceed by far their sole involvement as promoter kinases. Indeed, this original dogma has been subsequently redefined by the introduction of several new concepts: the identification of tumor suppressing roles for c/nPKCs, and their participation in early and late stages of carcinogenesis. This review dives deep into the intricate roles of c/nPKCs in cancer initiation as well as in the different stages of the metastatic cascade, with great emphasis in their involvement in cancer cell motility via regulation of small Rho GTPases, the production of extracellular matrix (ECM)-degrading proteases, and the epithelial-to-mesenchymal transition (EMT) program required for the acquisition of highly invasive traits. Here, we highlight functional interplays between either PKCα or PKCε and mesenchymal features that may ultimately contribute to anticancer drug resistance in cellular and animal models. We also introduce the novel hypothesis that c/nPKCs may be implicated in the control of immune evasion through the regulation of immune checkpoint protein expression. In summary, dissecting the colossal complexity of c/nPKC signaling in the wide spectrum of cancer progression may bring new opportunities for the development of meaningful tools aiding for cancer prognosis and therapy.

Non-coding RNAs in Brain Tumors, the Contribution of lncRNAs, circRNAs, and snoRNAs to Cancer Development-Their Diagnostic and Therapeutic Potential

Brain tumors are one of the most frightening ailments that afflict human beings worldwide. They are among the most lethal of all adult and pediatric solid tumors. The unique cell-intrinsic and microenvironmental properties of neural tissues are some of the most critical obstacles that researchers face in the diagnosis and treatment of brain tumors. Intensifying the search for potential new molecular markers in order to develop new effective treatments for patients might resolve this issue. Recently, the world of non-coding RNAs (ncRNAs) has become a field of intensive research since the discovery of their essential impact on carcinogenesis. Some of the most promising diagnostic and therapeutic regulatory RNAs are long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), and small nucleolar RNAs (snoRNAs). Many recent reports indicate the important role of these molecules in brain tumor development, as well as their implications in metastasis. In the following review, we summarize the current state of knowledge about regulatory RNAs, namely lncRNA, circRNAs, and snoRNAs, and their impact on the development of brain tumors in children and adults with particular emphasis on malignant primary brain tumors-gliomas and medulloblastomas (MB). We also provide an overview of how these different ncRNAs may act as biomarkers in these tumors and we present their potential clinical implications.

Huaier Restrains Cholangiocarcinoma Progression in vitro and in vivo Through Modulating lncRNA TP73-AS1 and Inducing Oxidative Stress

Purpose

Huaier, the fruiting body of Trametes robiniophila Murr, is a kind of traditional Chinese medicine. Recently, many studies have confirmed that Huaier has antitumor effects on various malignancies. Moreover, studies have demonstrated that long noncoding RNAs play an important regulatory role in the occurrence and progression of malignancies. Our present study was to explore whether Huaier has a potential antitumor effect in cholangiocarcinoma and reveal the relationship between lncRNAs and Huaier-induced tumor inhibition.

Methods

Microarray assay was performed to identify the candidate lncRNAs regulated by Huaier. Quantitative real-time PCR was applied to assess the effect of Huaier on TP73-AS1 expression. The effect of Huaier on the cell viability, proliferation, migration and invasion was evaluated by CCK-8, colony formation, wound healing and Transwell assays, respectively. The ratio of cell apoptosis was determined using AO/EB, Hoechst 33342 and flow cytometry. The effect of Huaier on oxidative stress was revealed using DCFH-DA, mito-SOX, JC-1 probes and Western blotting. In addition, the effect of Huaier on tumor growth and metastasis was explored using subcutaneous tumor model and lung metastatic tumor model in nude mice.

Results

In vitro, Huaier inhibited the proliferation, migration and invasion of cholangiocarcinoma cells by down-regulating TP73-AS1 and induced apoptosis through mitochondrial apoptotic pathway. In vivo, Huaier suppressed the growth and metastasis of cholangiocarcinoma by modulating the expression of proliferation and EMT-associated proteins.

Conclusion

Huaier could inhibit cell proliferation, invasion and metastasis by modulating the expression of TP73-AS1, meanwhile promote apoptosis of CCA cells through disturbing mitochondrial function, inducing oxidative stress and activating caspases in vitro. In addition, Huaier could suppress tumor growth and metastasis by regulating the expression of proliferation and EMT-related proteins. In the meantime, Huaier prolonged the survival of nude mice in lung metastatic model with acceptable drug safety.

Quantitative Proteomics Analysis Indicates That Upregulation of lncRNA HULC Promotes Pathogenesis of Glioblastoma Cells

Purpose

Glioblastoma (GBM) is an aggressive central nervous system (CNS) cancer and a serious threat to human health. The long noncoding RNA (lncRNA) HULC has been implicated in GBM, but the molecular mechanism is uncertain. This study used quantitative proteomic analysis for global identification of HULC-regulated proteins in glioblastoma cells and identification of potential biomarkers.

Materials and Methods

qRT-PCR was used to determine the expression of HULC in U87 cells stably transfected with HULC or an empty vector (control). The CCK-8 assay, transwell assay, and wound-scratch assay were used to measure cell proliferation, invasion, and migration. Quantitative proteomics using Tandem Mass Tag (TMT) labeling, high-performance liquid chromatography (HPLC) fractionation, and liquid chromatography–mass spectrometry (LC-MS/MS) analysis were used to identify differentially expressed proteins (DEPs). Screened proteins were validated by parallel reaction monitoring (PRM) and Western blotting.

Results

Overexpression of HULC led to increased cell proliferation, invasion, and migration. HULC overexpression also led to significant upregulation of 37 proteins and downregulation of 78 proteins. Bioinformatics analysis indicated these proteins had roles in cellular component, biological process, and molecular function. PRM results of 8 of these proteins (PTK2, TNC, ITGAV, LASP1, MAPK14, ITGA1, GNA13, RRAS) were consistent with the LC-MS/MS and Western blotting results.

Conclusion

The results of present study suggest that lncRNA HULC promotes GBM cell proliferation, invasion, and migration by regulating RRAS expression, suggesting that RRAS may be a potential biomarker or therapeutic target for this cancer.

Current advances of long non-coding RNAs mediated by wnt signaling in glioma

Glioma is the most common and aggressive brain tumor in the central nervous system (CNS), in which Wnt signaling pathway has been verified to play a pivotal role in regulating the initiation and progression. Currently, numerous studies have indicated that long non-coding RNAs (lncRNAs) have critical functions across biological processes including cell proliferation, colony formation, migration, invasion and apoptosis via Wnt signaling pathway in glioma. This review depicts canonical and non-canonical Wnt/β-catenin signaling pathway properties and relative processing mechanisms in gliomas, and summarizes the function and regulation of lncRNAs mediated by Wnt signaling pathway in the development and progression of glioma. Ultimately, we hope to seek out promising biomarkers and reliable therapeutic targets for glioma.

Comprehensive biological function analysis of lncRNAs in hepatocellular carcinoma

Thousands of long non-coding RNAs (lncRNAs) have been discovered in human genomes by gene chip, next-generation sequencing, and/or other methods in recent years, which represent a significant subset of the universal genes involved in a wide range of biological functions. An abnormal expression of lncRNAs is associated with the growth, invasion, and metastasis of various types of human cancers, including hepatocellular carcinoma (HCC), which is an aggressive, highly malignant, and invasive tumor, and a poor prognosis in China. With a more in-depth understanding of lncRNA research for HCC and the emergence of new molecular-targeted therapies, the diagnosis, treatment, and prognosis of HCC will be considerably improved. Therefore, this review is expected to provide recommendations and directions for future lncRNA research for HCC.

Identification of novel LncRNA targeting Smad2/PKCα signal pathway to negatively regulate malignant progression of glioblastoma

Glioblastoma multiforme (GBM) is a highly proliferative cancer with generally poor prognosis and accumulating evidence has highlighted the potential of long noncoding RNAs (lncRNAs) in the biological behaviors of glioma cells. This study focused on the identification of lncRNAs to identify targets for possible GBM prognosis. Microarray expression profiling found that 1,759 lncRNAs and 3,026 messenger RNAs (mRNAs) were upregulated, and 1932s lncRNA and 2,979 mRNAs were downregulated in GBM. Bioinformatics analysis and experimental verification identified TCONS_00020456 (TCON) for further analysis. In situ hybridization, along with immunohistochemical and receiver operating characteristic analysis determined TCON (truncation value = 3.5) as highly sensitive and specific in GBM. Grade IV patients with glioma life span with different lncRNA staining scores were analyzed. TCON staining scores below 3.5 indicated poor prognosis (life span ranging from 0.25 to 7 months), even if the glioma was surgically removed. TCON decreased significantly in GBM, and showed a coexpressional relationship with Smad2 and protein kinase C α (PKCα). Overexpression of TCON reduced the proliferation on one hand and migration, invasion on the other. TCON also inhibited epithelial–mesenchymal transformation and glioma progression in vivo, based on a nude mouse tumorigenicity assay. In addition, we predicted a potential binding site and intersection that microRNAs targeting Smad2, PKCα, and TCON through RACE pretest and bioinformatics analysis. Taken together, TCON, regarded as oncosuppressor, targeting the Smad2/PKCα axis plays a novel role in inhibiting the malignant progression of glioma. Moreover, it also demonstrates that the level of TCON can be used as a prognostic and diagnostic biomarker for GBM.