LncRNA PLAC2 down-regulates RPL36 expression and blocks cell cycle progression in glioma through a mechanism involving STAT1

Long Noncoding RNA NEAT1 Suppresses Proliferation and Promotes Apoptosis of Glioma Cells Via Downregulating MiR-92b

BACKGROUND

The mechanisms underlying the proliferation and apoptosis of glioma cells remain unelucidated. A recent study has revealed that microRNA-92b (miR-92b) inhibits apoptosis of glioma cells via downregulating DKK3. Notably, long noncoding RNA nuclear-enriched abundant transcript 1 (NEAT1) is predicted to have a possible interaction with miR-92b.

OBJECTIVE

This study aimed to identify whether NEAT1 affects glioma cell proliferation and apoptosis via regulating miR-92b.

METHODS

The expression of NEAT1 was compared between glioma tissues and adjacent tissues as well as between glioma cells and normal astrocytes using quantitative real-time polymerase chain reaction. Glioma cell proliferation was determined by using the 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and glioma cell apoptosis was determined by using the flow cytometry.

RESULTS

The expression of NEAT1 was low in glioma tissues and cells compared to the normal ones. Overexpression of NEAT1 inhibited proliferation and promoted apoptosis of glioma cell lines (U-87 MG and U251). The interaction between NEAT1 and miR-92b was confirmed using RNA immunoprecipitation, RNA pull-down assay, and luciferase reporter assay. Importantly, the tumor suppressor function of overexpressing NEAT1 was achieved by downregulating miR-92b and subsequently upregulating DKK3.

CONCLUSION

Our findings indicated that NEAT1 acts as a tumor suppressor in glioma cells, which provides a novel target in overcoming glioma growth.

Long noncoding RNA HOTAIRM1 in human cancers

Long noncoding RNAs (lncRNAs) are a group of RNAs over 200 nucleotides in length involved in diverse processes in tumor cells including proliferation, invasion and apoptosis. Given these facts, it is hardly accidental that variations in the expression of some lncRNAs have been found to be closely related to carcinogenesis and tumor growth and metastasis. HOTAIRM1, first discovered as an important factor for granulocytic differentiation in NB4 promyelocytic leukemia, has been shown to be a salient cancer-related lncRNA abnormally expressed in a variety of tumors. In this review, we summarize current evidence on the critical role of HOTAIRM1 in human malignancy, its potential mechanism of action and future use in the development of effective therapeutics.

Epigenetic Mechanisms of LncRNAs Binding to Protein in Carcinogenesis

Epigenetic dysregulation is an important feature for cancer initiation and progression. Long non-coding RNAs (lncRNAs) are transcripts that stably present as RNA forms with no translated protein and have lengths larger than 200 nucleotides. LncRNA can epigenetically regulate either oncogenes or tumor suppressor genes. Nowadays, the combined research of lncRNA plus protein analysis is gaining more attention. LncRNA controls gene expression directly by binding to transcription factors of target genes and indirectly by complexing with other proteins to bind to target proteins and cause protein degradation, reduced protein stability, or interference with the binding of other proteins. Various studies have indicated that lncRNA contributes to cancer development by modulating genes epigenetically and studies have been done to determine which proteins are combined with lncRNA and contribute to cancer development. In this review, we look in depth at the epigenetic regulatory function of lncRNAs that are capable of complexing with other proteins in cancer development.

Long noncoding RNA HCG11 inhibited growth and invasion in cervical cancer by sponging miR-942-5p and targeting GFI1

Long noncoding RNAs (lncRNAs) act as essential regulators in cancer tumorigenesis. Our study aimed to explore the underlying mechanism of lncRNA human leukocyte antigen complex group 11 (HCG11) in cervical cancer (CC) progression. Long noncoding RNA HCG11 was downregulated in CC. Functional assays demonstrated that lncRNA HCG11 inhibited CC cell proliferation and invasion. Then, we confirmed that lncRNA HCG11 could directly bind to miR-942-5p. Moreover, inhibition of miR-942-5p suppressed the growth and invasion of CC cells, and growth factor-independent transcription repressor 1 (GFI1) gene was the target gene of miR-942-5p. Long noncoding RNA HCG11 increased the expression of GFI1 and suppressed cell proliferation and invasion by acting as a miR-942-5p sponge. Finally, the overexpression of lncRNA HCG11 suppressed the proliferation and metastasis of CC cells in vivo.

TTDA inhibited apoptosis by regulating the p53-Bax/Bcl2 axis in glioma

The trichothiodystrophy group A protein (TTDA) functions in nucleotide excision repair and basal transcription. TTDA plays a role in cancers and serves as a prognostic and predictive factor in high-grade serous ovarian cancer; however, its role in human glioma remains unknown. Here, we found that TTDA was overexpressed in glioma tissues. In vitro experiments revealed that TTDA overexpression inhibited apoptosis of glioma cells and promoted cell growth, whereas knockdown of TTDA had the opposite effect. Increased TTDA expression significantly decreased the Bax/Bcl2 ratio and the level of cleaved-caspase3. TTDA interacted with the p53 gene at the -1959 bp and -1530 bp region and regulated its transcription, leading to inhibition of the p53-Bax/Bcl2 mitochondrial apoptosis pathway in glioma cells. These results indicate that TTDA is an upstream regulator of p53-mediated apoptosis and acts as an oncogene, suggesting its value as a potential molecular target for the diagnosis and treatment of glioma.

Roles of long non-coding RNAs in the hallmarks of glioma

Glioma is one of the most common types of tumor of the central nervous system. Due to the aggressiveness and invasiveness of high-level gliomas, the survival time of patients with these tumors is short, at ~15 months, even after combined treatment with surgery, radiotherapy and/or chemotherapy. Recently, a number of studies have demonstrated that long non-coding RNA (lncRNAs) serve crucial roles in the multistep development of human gliomas. Gliomas acquire numerous biological abilities during multistep development that collectively constitute the hallmarks of glioma. Thus, in this review, the roles of lncRNAs associated with glioma hallmarks and the current and future prospects for their development are summarized.

LncRNA PLAC2 Positively Regulates CDK2 to Promote Ovarian Carcinoma Cell Proliferation

Background

PLAC2 has been reported to participate in glioma, but its role in ovarian carcinoma (OC) is unclear. This study investigated the role of lncRNA PLAC2 in OC.

Methods

A 5-year follow-up study of 64 patients was carried out in Weihai Municipal Hospital after the admission of patients. A total of 64 OC patients were selected from 178 OC patients admitted in the aforementioned hospital from August 2011 to January 2014. Cell transfections, cell cycle analysis, cell proliferation assay and Western blot were carried out during the research.

Results

The expression levels of PLAC2 and CDK2 were both upregulated in OC and they were positively correlated. During the 5-year follow-up, patients with high levels of PLAC2 and CDK2 showed significantly lower overall survival rate. In OC cells, overexpression of PLAC2 resulted in upregulated, while silencing of PLAC2 resulted in downregulated expression of CDK2. Cell proliferation assay showed that overexpression of PLAC2 resulted in increased, while silencing of PLAC2 resulted in decreased proliferation rate of OC cells. In addition, overexpression of CDK2 attenuated the effects of silencing of PLAC2.

Conclusion

PLAC2 positively regulates CDK2 to promote OC cell proliferation.

LncRNA PLAC2 upregulates miR-663 to downregulate TGF-β1 and suppress bladder cancer cell migration and invasion

BACKGROUND

The roles of lncRNA PLAC2 in bladder cancer (BC) were explored.

METHODS

The expression of PLAC2 in two types of tissue of BC patients was detected by RT-qPCR and the expression data were compared by paired t test. The 56 patients were staged according to the AJCC criteria, and 12, 15, 15 and 14 cases were classified into stage I-IV, respectively. The expression of TGF-β1 and miR-663 in BC tissues were also detected by RT-qPCR experiments.

RESULTS

Our data showed that the expression levels of PLAC2 were significantly lower in BC tissues than that in non-cancer tissues. The expression of PLAC2 was not affect by clinical stages and low expression levels of PLAC2 predicted lower survival rate. The expression of PLAC2 was positively correlated with miR-663 and inversely correlated with TGF-β1 in BC tissues. In BC cells, downregulated TGF-β1 and upregulated miR-663 were observed after the overexpression of PLAC2. Overexpression of PLAC2 also resulted in suppressed invasion and migration of BC cells. Overexpression of miR-663 resulted in downregulated TGF-β1 but did not affect the expression of PLAC2. Overexpression of TGF-β1 reduced the inhibitory effects of overexpression of PLAC2 and miR-663 on cell migration and invasion.

CONCLUSION

PLAC2 can upregulate miR-663 to downregulate TGF-β1 and suppress BC cell migration and invasion.

TINCR: An lncRNA with dual functions in the carcinogenesis process

Long non-coding RNAs (lncRNAs) have prominent roles in the pathogenesis of human cancers. Several studies have shown oncogenic or tumor suppressor roles of lncRNAs in different human tissues. Thus, these transcripts have been regarded as putative targets in treatment of cancer. The lncRNA terminal differentiation-induced non-coding RNA (TINCR) has an especial position in this regard, as it exerts different opposite roles in the pathogenesis of different human cancers. While it is up-regulated in gastric, esophageal, bladder and breast cancer; it is down-regulated in glioma, retinoblastoma and prostate cancer. Notably, data regarding expression profile of this lncRNA in a number of human cancers such as colon cancer, squamous cell carcinoma, non-small cell lung cancer (NSCLC) and hepatocellular carcinoma (HCC) are controversial. Expression level of this lncRNA has been associated with clinical outcome in patients with gastric cancer, colorectal cancer, NSCLC and head and neck squamous cell carcinoma. Moreover, Kaplan-Meier analyses have shown correlation between expression levels of TINCR and patients survival in patients with lung cancer and HCC. A number of cellular pathways such as Wnt/β-catenin, ERK1/2‐SP3 and MAPK signaling pathways have been identified as targets of this lncRNA in different cancers. Moreover, the rs8113645, rs2288947 and rs8105637 within this lncRNA have been associated with risk of gastric and colorectal cancer. In conclusion, although the role of TINCR in the carcinogenesis is essential, based on the conflicting data regarding the direction of effect of this lncRNA, therapeutic targeting of this lncRNA is a complicated issue which should be considered in a tissue-specific or even individualized manner.

LINC00294 negatively modulates cell proliferation in glioma through a neurofilament medium-mediated pathway via interacting with miR-1278

BACKGROUND

Accumulating long noncoding RNAs (lncRNAs) have been recognized to participate in glioma development. Nevertheless, knowledge of the role of linc00294 in glioma remains incomplete.

METHODS

Bioinformatics analysis predicted the differential expression of LINC00294 and neurofilament medium (NEFM) in tumors and normal tissues, as well as the binding between LINC00294 and miR-1278, miR-1278 and NEFM. Luciferase and RNA immunoprecipitation assays were used for the verification of interactions. The potential role of LINC00294 in glioma development was investigated using functional assays, singly and in parallel with its interplay with miR-1278 and NEFM. Cell counting kit-8 and EdU assays were applied to measure cellular proliferation, whereas the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method was employed to detect apoptosis.

RESULTS

A new lncRNA, LINC00294, was highly expressed in normal brain tissues. However, it was markedly down-regulated in GBM tissues and glioma cell lines. Overexpression of LINC00294 abates glioma cell proliferation but induces apoptosis. Meanwhile, tumor suppressor NEFM was revealed to be distinctly diminished in cancerous conditions and enhanced in glioma cells by LINC00294 up-regulation. Interactions of miR-1278 with LINC00294 or NEFM occur, and the expression of NEFM is up-regulated by LINC00294 through their competition with respect to binding to miR-1278. Finally, the rescue assays further confirmed that LINC00294 inhibits glioma cell proliferation by absorbing miR-1278 to enhance NEFM.

CONCLUSIONS

Collectively, our observations demonstrate the tumor-suppressive function of LINC00294 in glioma development by sponging miR-1278 and promoting NEFM, suggesting a potential use in therapy for glioma.

LncRNA PLAC 2 Is Downregulated in Osteosarcoma and Regulates Cancer Cell Proliferation Through miR-93

Introduction

PLAC 2 is a tumor-suppressive lncRNA in glioma, while its roles in other types of cancer remain unclear. This study was carried out to explore the potential involvement of PLAC 2 in osteosarcoma (OS).

Methods

Expression levels of PLAC 2 in OS and paired non-tumor tissues from OS patients were determined by RT-qPCR. A follow-up study was performed to analyze the prognostic value of PLAC 2 for OS. Interactions between PLAC 2 and miR-93 were assessed by cell transfection, followed by RT-qPCR. Cell proliferation assay was performed to analyze cell proliferation.

Results

Our results showed that PLAC 2 was downregulated in OS tissues, and the high expression levels of PLAC 2 were associated with favorable overall survival of OS patients. MiR-93 was upregulated in OS tissues and its expression was inversely correlated with the expression of PLAC 2. In OS cells, overexpression of PLAC 2 resulted in downregulated miR-93, while overexpression of miR-93 did not affect the expression of PLAC 2. Overexpression of PLAC 2 led to decreased proliferation rate of OS cells, while overexpression of miR-93 showed opposite roles and reduced the overexpressing effects of PLAC 2.

Conclusion

PLAC 2 is downregulated in OS and regulates cancer cell proliferation through miR-93.

STAT1 determines aggressiveness of glioblastoma both in vivo and in vitro through wnt/β-catenin signalling pathway

Glioblastoma is one of the most malignant tumors and causes the high mortality in cancer patients. Currently, there is no highly efficient therapy against glioblastoma. Therefore, searching for a new molecular target to anti-glioblastoma therapy is urgent and necessary. In this study, we elucidated the role of Signal transducer and activator of transcription 1 (STAT1) in proliferation, migration and apoptosis of glioblastoma cells. We found that STAT1 downregulation could weaken the aggressiveness of glioblastoma cells. Besides, the glioblastoma growth in vivo was also inhibited with the STAT1 downregulation by shRNA as well as by pharmacological stimulation withSTAT1inhibitors. This negative regulation of tumor growth was accompanied by the inhibition in epithelial-mesenchymal transition (EMT), whereas the STAT1 overexpression promoted EMT. Furthermore, the involvement of wnt/β-catenin was observed in STAT1 downregulation mediated weakness in glioblastoma aggressiveness since application of activator wnt agonist 1 could counteract the inhibitory effect induced by STAT1 downregulation. Collectively, this work provided the evidence to support the conclusion that STAT1 can regulate the glioblastoma growth and migration, potentially serving as a therapeutic target against glioblastoma. SIGNIFICANCE OF THE STUDY: Glioblastoma is one of the most malignant tumors with very high mortality. Until now, there is no efficient therapy against glioblastoma. In this study, we found downregulation of Signal transducer and activator of transcription 1 (STAT1) could weaken the aggressiveness of glioblastoma cells through inhibition in epithelial-mesenchymal transition, mediated through wnt/β-catenin signalling pathway. Thus, this work supported the regulatory role of STAT1 in glioblastoma growth and migration. This potentially serves as a new therapeutic target against glioblastoma.

LINC01198 facilitates gliomagenesis through activating PI3K/AKT pathway

Glioma is the most malignant primary brain cancer which frequently occurred in adults. In recent years, long-non coding RNAs (lncRNAs) have been demonstrated to play pivotal roles in human cancers. However, the role of most lncRNAs in gliomagenesis has not been probed. Presently, through TCGA, a novel lncRNA LINC01198 was found to be up-regulated and associated with clinical outcomes in glioblastoma multiforme (GBM). In our study, LINC01198 was proved to be up-regulated in glioma cell lines, and silenced LINC01198 curbed glioma cell proliferation and accelerated cell apoptosis. Importantly, we corroborated that LINC01198 activated the PI3 K/AKT pathway to aggravate glioma progression by targeting PIK3 CA and PTEN. Subsequently, LINC01198 was validated to localize in both cytoplasm and nucleus of glioma cells. Through mechanistic exploration, we illustrated that LINC01198 increased PIK3CA expression by sponging miR-129-5p in the cytoplasm. Furthermore, PTEN was transcriptionally repressed by REST/RCOR1/HDAC2 complex. More importantly, LINC01198 accelerated the assembly of REST/RCOR1/HDAC2 complex and recruited such complex to PTEN promoter so as to impair PTEN expression in glioma. Finally, we further verified that LINC01198 hindered glioma tumour growth in vivo through AKT-dependent manner. Jointly, LINC01198 activates PI3 K/AKT signalling to exert oncogenic function in gliomagenesis by regulating PIK3CA and PTEN, which highlights a new approach for glioma treatment.

Long Noncoding RNA GM16343 Promotes IL-36β to Regulate Tumor Microenvironment by CD8+T cells

Objective:

To investigate the effect of long noncoding RNA GM16343 on interleukin 36β promotion of CD8⁺T cells in tumor microenvironment regulation.

Methods:

The differentially expressed long noncoding RNA in interleukin 36β-stimulated mouse CD8⁺T cells was screened by gene chip technology, and the significant differentially expressed long noncoding RNAs were verified by real-time polymerase chain reaction. The lentiviral vector that overexpresses or knockdown GM16343 was constructed, transfected into CD8⁺T cells, and stimulated with interleukin 36β, and the amount of interferon γ secreted was detected by enzyme-linked immunosorbent assay. A mouse subcutaneous xenograft model that stably express interleukin 36β was established, and the tumor size and mouse survival time were observed by stimulation with CD8⁺T cells overexpression or knockdown of GM16343.

Results:

A total of 12 long noncoding RNAs with significant differences were screened by gene chip analysis. Real-time polymerase chain reaction showed that the difference in GM16343 was larger, and the difference between the groups was observed to be the most significant. Compared to control group, CD8⁺T cells overexpressing GM16343 increased the secretion of interferon γ, and the tumor diameter of the mice after stimulation showed significant reduction, and the survival time showed significant prolongation. Compared to control group, the CD8⁺T cells after GM16343 were knocked down. The interferon γ secretion was decreased, and no significant change in tumor diameter and survival time was observed.

Conclusion:

Interleukin 36β may enhance antitumor immune response of CD8⁺T cells by regulating GM16343.

IL-2 enhances ex vivo-expanded regulatory T-cell persistence after adoptive transfer

As regulatory T cell (Treg) adoptive therapy continues to develop clinically, there is a need to determine which immunomodulatory agents pair most compatibly with Tregs to enable persistence and stabilize suppressor function. Prior work has shown that mechanistic target of rapamycin inhibition can increase the stability of thymic Tregs. In this study, we investigated the transcriptomic signatures of ex vivo-expanded Tregs after adoptive transfer in the setting of clinically relevant immunosuppression using a nonhuman primate (NHP) model as a prelude to future transplant studies. Here, we found that adding interleukin-2 (IL-2) to rapamycin in vivo supported a logarithmic increase in the half-life of adoptively transferred carboxyfluorescein diacetate succinimidyl ester-labeled, autologous NHP Tregs, effectively doubling the number of cells in the peripheral blood Treg compartment compared with Treg infusion when rapamycin was given alone. Using single-cell transcriptomics, we found that transferred ex vivo-expanded Tregs initially exhibit a gene expression signature consistent with an activated state. Moreover, those cells with the highest levels of activation also expressed genes associated with p53-mediated apoptosis. In contrast, transferred Tregs interrogated at day +20 posttransfer demonstrated a gene signature more similar to published profiles of resting Tregs. Together, these preclinical data further support combining IL-2 and rapamycin in vivo as adjunctive therapy for ex vivo-expanded adoptively transferred Tregs and suggest that the activation status of ex vivo-expanded Tregs is critical to their persistence.

A comprehensive evaluation of differentially expressed mRNAs and lncRNAs in cystitis glandularis with gene ontology, KEGG pathway, and ceRNA network analysis

BACKGROUND

Cystitis glandularis (CG) is a proliferative disorder of the urinary bladder characterized by transitional cells that have undergone glandular metaplasia. The underlying mechanism associated with this transformation is poorly understood.

METHODS

The expression of messenger RNA (mRNA) and long non-coding RNA (lncRNA) from normal bladder mucosa and CG were compared using microarray analysis. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was used to describe molecular interactions.

RESULTS

Microarray analysis identified 809 significantly dysregulated mRNAs in CG tissues; 606 were up-regulated and 203 were down-regulated (greater than 2-fold difference in expression from normal tissue, P<0.05). KEGG pathway analysis showed that the mRNAs that co-expressed with lncRNAs were enriched in the cell cycle regulation pathway. Four up-regulated lncRNAs (ENST00000596379, ENST00000463397, NR_001446 and NR_015395) were identified in the coding-non-coding co-expression (CNC) network analysis as being associated with the expression of four mRNAs (SMAD3, ORC1, CCNA2 and CCNB2). NR_015395 was revealed to be a competing endogenous RNA (ceRNA) of miR-133a-3p that targets SMAD3.

CONCLUSIONS

This is the first work to measure the expression of dysregulated lncRNA and ceRNA in CG and identify the crosstalk between mRNA and lncRNA expression patterns in the pathogenesis of CG.

Long noncoding RNA SNHG17 induced by YY1 facilitates the glioma progression through targeting miR-506-3p/CTNNB1 axis to activate Wnt/β-catenin signaling pathway

Background

Glioma is one of the most widely diagnosed malignancies worldwide. It has been reported that long noncoding RNAs (lncRNAs) are participators in the tumorgenesis of cancers. Nevertheless, the role and function of lncRNA SNHG17 among glioma is unclear.

Methods

RT-qPCR revealed SNHG17, YY1, miR-506-3p, CTNNB1 expression among glioma cells. CCK-8, colony formation, EdU, flow cytometry, TUNEL and western blot assays revealed the function of SNHG17 in glioma. RIP uncovered SNHG17, miR-506-3p and CTNNB1 enrichment in RISC complex. Luciferase reporter assays and RNA pull down revealed interaction of miR-506-3p with SNHG17 and CTNNB1.

Results

SNHG17 expression was up-regulated in glioma tissues and cells. SNHG17 silence attenuated cell proliferation and promoted apoptosis and repressed tumor growth. Moreover, SNHG17 was up-regulated by transcription factor YY1. Mechanistically, SNHG17 activated Wnt/β-catenin signaling pathway in glioma. CTNNB1 was referred to as the mRNA of β-catenin, we validated that SNHG17 bound to miR-506-3p to induce CTNNB1 and activate Wnt/β-catenin signaling pathway. Rescue experiments indicated that CTNNB1 overexpression abolished the inhibitory effects of SNHG7 inhibition on glioma progression.

Conclusions

The findings that YY1-induced SNHG17 facilitated the glioma progression through targeting miR-506-3p/CTNNB1 axis to activate Wnt/β-catenin signaling pathway offered a brand-new prospects to molecular-targeted treatment for glioma.

Long noncoding RNA PLAC2 regulates PTEN in retinoblastoma and participates in the regulation of cancer cell apoptosis

Long noncoding RNA placenta-specific 2 (PLAC2) blocks the cancer cell cycle in glioma, suggesting its tumor-suppressive role. The present study aimed to investigate the role of PLAC2 in retinoblastoma (Rb). It was found that PLAC2 was downregulated in Rb tissues and was not affected by the development of Rb. PTEN was also downregulated in Rb and positively correlated with PLAC2. In Rb cells, PLAC2 over-expression resulted in the upregulated expression of PTEN, while PTEN over-expression did not affect PLAC2 expression. PLAC2 and PTEN over-expression caused an increased apoptotic rate of Rb cells. PTEN small interfering RNA silencing led to a decreased apoptotic rate and attenuated the effects of PLAC2 over-expression. Therefore, PLAC2 regulates PTEN in Rb and participates in the regulation of cancer cell apoptosis.

The emerging role of long non-coding RNAs in tumor-associated macrophages

Tumor-associated macrophages (TAMs) are an important cellular component of the tumor microenvironment (TME) and play an essential role in tumor immunity. Recently, numerous studies have indicated that long non-coding RNAs (lncRNAs) can affect several functions of TAMs. In the present review, we summarize the versatile role of lncRNAs in the polarization, epigenetic modulation, and classic signaling pathways of TAMs, which represent a potential target for tumor diagnosis or treatment.

Genome-wide discovery and characterization of long noncoding RNAs in patients with multiple myeloma

Background

Long noncoding RNAs (lncRNAs) are involved in a wide range of biological processes in tumorigenesis. However, the role of lncRNA expression in the biology, prognosis, and molecular classification of human multiple myeloma (MM) remains unclear, especially the biological functions of the vast majority of lncRNAs. Recently, lncRNAs have been identified in neoplastic hematologic disorders. Evidence has accumulated on the molecular mechanisms of action of lncRNAs, providing insight into their functional roles in tumorigenesis. This study aimed to characterize potential lncRNAs in patients with MM.

Methods

In this study, the whole-transcriptome strand-specific RNA sequencing of samples from three newly diagnosed patients with MM was performed. The whole transcriptome, including lncRNAs, microRNAs, and mRNAs, was analyzed. Using these data, MM lncRNAs were systematically analyzed, and the lncRNAs involved in the occurrence of MM were identified.

Results

The results revealed that MM lncRNAs had distinctive characteristics different from those of other malignant tumors. Further, the functions of a set of lncRNAs preferentially expressed in MM were verified, and several lncRNAs were identified as competing endogenous RNAs. More importantly, the aberrant expression of certain lncRNAs, including maternally expressed gene3, colon cancer–associated transcript1, and coiled-coil domain-containing 26, as well as some novel lncRNAs involved in the occurrence of MM was established. Further, lncRNAs were related to some microRNAs, regulated each other, and participated in MM development.

Conclusions

Genome-wide screening and functional analysis enabled the identification of a set of lncRNAs involved in the occurrence of MM. The interaction exists among microRNAs and lncRNAs.

LncRNA PLAC 2 downregulated miR-21 in non-small cell lung cancer and predicted survival

Background

LncRNA PLAC2 has been characterized as a tumor suppressive lncRNA in glioma. We investigated the role of PLAC2 in non-small cell lung cancer (NSCLC).

Methods

A total of 187 NSCLC patients were admitted by The First Hospital of Jilin University from December 2010 to December 2014. All the patients were diagnosed by histopathological approaches. Transient cell transfections, RT-qPCR, invasion, and migration ability measurement, were applied for the experiments.

Results

PLAC2 was down-regulated, while miR-21 was up-regulated in NSCLC tissues compared to non-cancer tissues. Low PLAC2 levels in NSCLC tissues were associated with poor survival of NSCLC patients. PLAC2 and miR-21 were inversely correlated, and PLAC 2 over-expression in NSCLC cells resulted in the down-regulation of miR-21. However, miR-21 over-expression did not significantly affect PLAC2 expression. In addition, PLAC2 over-expression resulted in decreased migration and invasion rates of NSCLC cells. MiR-21 over-expression played the opposite role and attenuated the effects of PLAC2 over-expression.

Conclusions

In conclusion, lncRNA PLAC2 down-regulated miR-21 in NSCLC and inhibited cancer cell migration and invasion.

Long noncoding RNA HAS2-AS1 promotes tumor progression in glioblastoma via functioning as a competing endogenous RNA

Glioblastoma multiforme (GBM) is a refractory tumor with poor prognosis and requires more effective treatment regimens. It has been confirmed that long noncoding RNAs (lncRNAs) substantially regulate various human disease including GBM. However, the biological roles and its underlying molecular mechanisms still need to be further investigated. In this study, the biological function and potential molecular mechanism of lncHAS2-AS1 in GBM were explored. It was discovered that HAS2-AS1 was elevated in glioma tissues and correlated with the prognosis of patients with glioma. Reduction of HAS2-AS1 suppressed the migration and invasion in vitro and in vivo. The transcription factor STAT1 could raise HAS2-AS1 by binding to its promoter region. Besides, HAS2-AS1 could adjust PRPS1 via sponging miR-608 in a direct manner. On the whole, the results of this study evidence that HAS2-AS1 is an oncogene and a potential therapeutic target for GBM.

LncRNA PLAC2 upregulates p53 to induce hepatocellular carcinoma cell apoptosis

It is known that lncRNA PLAC2 can inhibit glioma. This study explored the function of PLAC2 in hepatocellular carcinoma (HCC). Our data showed that PLAC2 expression in HCC was not affect by HCV and HBV infection, while PLAC2 levels were significantly lower in HCC tissues comparing to non-cancer tissues. Low PLAC2 levels in HCC tissues were associated with low overall 5-year survival rate. P53 mRNA was also downregulated in HCC and positively correlated with PLAC2. PLAC2 overexpression caused upregulated p53 and increase cancer cell apoptosis. P53 overexpression failed to affect PLAC2. In addition, p53 silencing reduced the effects of PLAC2 overexpression. Therefore, PLAC2 upregulated p53 to mediate cancer cell apoptosis.

The binding of lncRNA RP11-732M18.3 with 14-3-3 β/α accelerates p21 degradation and promotes glioma growth

Background

Long noncoding RNAs (lncRNAs) have been identified as regulators of a number of developmental and tumorigenic processes. However, the functions of most lncRNAs in glioma remain unknown and the mechanisms governing the proliferation of tumor cells remain poorly defined.

Methods

Both in vitro and in vivo assays were performed to investigate the roles of lncRNAs in the pathophysiology of gliomas. lncRNA arrays were used to identify differentially expressed lncRNAs. Subcutaneous tumor formation and a brain orthotopic tumor model in nude mice were used to investigate the functions of lncRNAs in vivo. The in vitro functions of lncRNAs were analyzed by fluorescence-activated cell sorting, colony formation, and western blot analyses. RNA fluorescence in situ hybridization and immunoprecipitation were used to explore the underlying mechanisms.

Findings

Here, we describe the newly discovered noncoding RNA RP11-732M18.3, which is highly overexpressed in glioma cells and interacts with 14-3-3β/α to promote glioma growth, acting as an oncogene. Overexpression of lncRNA RP11-732 M18.3 was associated with the proliferation of glioma cells and tumor growth in vitro and in vivo. Remarkably, lncRNA RP11-732M18.3 promoted cell proliferation and G1/S cell cycle transition. lncRNA RP11-732M18.3 is predominately localized in the cytoplasm. Mechanistically, the interaction of lncRNA RP11-732M18.3 with 14-3-3β/α increases the degradation of the p21 protein. lncRNA RP11-732M18.3 promoted the recruitment of ubiquitin-conjugating enzyme E2 E1 to 14-3-3β/α and the binding of 14-3-3β/α with ubiquitin-conjugating enzyme E2 E1 (UBE2E1) promoted the degradation of p21.

Interpretation

Overall these data demonstrated that lncRNA RP11-732M18.3 regulates glioma growth through a newly described lncRNA-protein interaction mechanism. The inhibition of lncRNA RP11-732M18.3 could provide a novel therapeutic target for glioma treatment.

Bortezomib-inducible long non-coding RNA myocardial infarction associated transcript is an oncogene in multiple myeloma that suppresses miR-29b

Clinical outcomes of patients with multiple myeloma (MM) have almost doubled the overall survival over the last decade owing to the use of proteasome inhibitor such as bortezomib (BTZ). However, some patients with MM develop primary resistance to BTZ, whereas others develop resistance after treatment. In this study, we investigated relationships between BTZ resistance and dysfunction of long non-coding RNAs (lncRNAs) in patients with MM. Bone marrow samples were collected from patients with MM and healthy donors for lncRNA microarray and survival analyses. To investigate functions and underlying mechanisms of lncRNA-mediated BTZ resistance in MM, we performed CCK-8 assays, flow cytometry analyses, dual luciferase report gene assays, and RNA pulldown assays with samples from nude mice carrying tumor xenografts and in clinical samples. Differentially expressed lncRNA myocardial infarction associated transcripts (MIAT) were highly expressed in patients with MM compared with healthy controls, and were predictive of poor survival outcomes. Moreover, MIAT expression was significantly increased in BTZ-resistant patients with MM compared with newly diagnosed patients with MM, and was identified as a BTZ-inducible lncRNA. Specifically, BTZ upregulated MIAT expression through increased stat1 phosphorylation. Silencing of MIAT inhibited MM cell growth and sensitized MM cells to BTZ by negatively regulating miR-29b. Our data demonstrated the utility of MIAT as a tool for overcoming BTZ resistance in patients with MM.

lncRNA PLAC2 activated by H3K27 acetylation promotes cell proliferation and invasion via the activation of Wnt/β‑catenin pathway in oral squamous cell carcinoma

As a new group of important effector molecules involved in multiple cancer types, including breast cancer, lung cancer and oral squamous cell carcinoma, long noncoding RNAs (lncRNAs) have attracted considerable attention recently. However, the underlying cause that induces the dysregulated lncRNAs in cancer remains poorly understood. In the present study, the regulatory model of the lncRNA placenta‑specific protein 2 (PLAC2) upregulation in oral squamous cell carcinoma (OSCC) was investigated and its biological functions in OSCC malignant progression was identified. A reverse transcription‑quantitative polymerase chain reaction assay identified that PLAC2 is upregulated in OSCC cell lines and primary tissue samples. Furthermore, bioinformatic analysis followed by chromatin immunoprecipitation verified an enriched histone H3 on lysine 27 (H3K27) acetylation (H3K27ac) at the promoter region of the PLAC2 gene. Knockdown of cAMP‑response element binding protein‑binding protein (CBP) significantly reduced the enrichment level of H3K27ac, and thereby induced a decreased expression of PLAC2. Functionally, overexpression of PLAC2 promotes OSCC cell proliferation, migration and invasion, whereas knockdown of PLAC2 exerted an opposite effect. Furthermore, the Wnt/β‑catenin signaling pathway was activated by PLAC2 and mediated the PLAC2‑induced malignant progress of OSCC. In conclusion, the present results indicated that lncRNA PLAC2 is transcriptionally activated by H3K27ac modification at the promoter region in OSCC, and promotes cell growth and metastasis via activating Wnt/β‑catenin signaling pathway. Therefore, PLAC2 may serve as a promising biomarker for OSCC prognosis and therapy.

The Chinese Medicinal Formulation Guzhi Zengsheng Zhitongwan Modulates Chondrocyte Structure, Dynamics, and Metabolism by Controlling Multiple Functional Proteins

Traditional Chinese medicine is one of the oldest medical systems in the world and has its unique principles and theories in the prevention and treatment of human diseases, which are achieved through the interactions of different types of materia medica in the form of Chinese medicinal formulations. GZZSZTW, a classical and effective Chinese medicinal formulation, was designed and created by professor Bailing Liu who is the only national medical master professor in the clinical research field of traditional Chinese medicine and skeletal diseases. GZZSZTW has been widely used in clinical settings for several decades for the treatment of joint diseases. However, the underlying molecular mechanisms are still largely unknown. In the present study, we performed quantitative proteomic analysis to investigate the effects of GZZSZTW on mouse primary chondrocytes using state-of-the-art iTRAQ technology. We demonstrated that the Chinese medicinal formulation GZZSZTW modulates chondrocyte structure, dynamics, and metabolism by controlling multiple functional proteins that are involved in the cellular processes of DNA replication and transcription, protein synthesis and degradation, cytoskeleton dynamics, and signal transduction. Thus, this study has expanded the current knowledge of the molecular mechanism of GZZSZTW treatment on chondrocytes. It has also shed new light on possible strategies to further prevent and treat cartilage-related diseases using traditional Chinese medicinal formulations.

Long noncoding RNA DLX6-AS1 accelerates the glioma carcinogenesis by competing endogenous sponging miR-197-5p to relieve E2F1

Long noncoding RNAs (lncRNAs) participate in numerous of human cancer tumorigenesis. Nevertheless, the in-depth molecular mechanism that lncRNAs regulate the gliomagenesis is still ambiguous. In this research, our study invests energy in the biologic roles of lncRNA DLX6-AS1 on the glioma tumorigenesis. Here, we demonstrated that DLX6-AS1 expression was both high-expressed in the glioma cells and tissue, and the overexpression of DLX6-AS1 was clinically correlated with the poor outcome of glioma patients. In the cellular functional assays, silenced DLX6-AS1 expression by siRNAs inhibited the proliferation, invasion and tumor growth in vitro and in vivo, while the enhanced DLX6-AS1 expression by plasmids promotes them. The bioinformatics predictive tools, luciferase reporter assay and correlation analysis found that miR-197-5p could both target the 3'-UTR of DLX6-AS1 as well as E2F1 gene, constructing DLX6-AS1-miR-197-5p-E2F1 axis. Moreover, receiver operating characteristic (ROC) curve analysis revealed that lncRNA DLX6-AS1 has valuable diagnostic value clinical diagnose for the glioma patients (AUC = 0.736). Overall, our finding supports that DLX6-AS1 accelerates the glioma carcinogenesis by competing endogenous sponging miR-197-5p to relieve E2F1, acting as a novel therapeutic target for glioma.

Roseburia intestinalis-derived flagellin is a negative regulator of intestinal inflammation

Our previous study showed that the Roseburia intestinalis (R. intestinalis), one of the dominant intestinal bacterial microbiota, was significantly decreased in Crohn's disease patients and protected colon epithelial cells from inflammatory damage. However, the roles of lncRNAs in R. intestinalis flagellin-mediated anti-inflammation remain unclear. In this study, we investigate global lncRNA expression profiles using microarray analysis of ulcerative colitis samples from DSS/Flagellin-challenged mice and identified a Flagellin-induced upregulated lncRNA (HIF1A-AS2). Flagellin induced HIF1A-AS2 expression in a dose- and time-dependent manner via p38-stat1 activation. Selective pharmacological inhibitors of Stat1 and p38, and genetic knockdown of these genes abolished Flagellin-induced HIF1A-AS2 expression. In addition, luciferase reporter assay showed that Flagellin activated HIF1A-AS2 promotor via increasing stat1 phosphorylation. Silencing of HIF1A-AS2 abolished Flagellin-mediated anti-inflammatory effects, evaluating by upregulation of cytokines expression, including TNF-α, IL-1β, IL-6 and IL-12, but not TNFβ. In addition, knockdown of HIF1A-AS2 significantly increased p65 and Jnk phosphorylation, and sufficiently abolished Flagellin-mediated anti-inflammatory affects in vivo. Our study provides new insights into the mechanisms that lncRNAs regulate flagellin-mediated alleviation of colonic inflammation. It is indicated that HIF1A-AS2 may be a modulator of intestinal inflammation and represent a novel target for future therapeutics.

Molecular Determinants of Malignant Brain Cancers: From Intracellular Alterations to Invasion Mediated by Extracellular Vesicles

Malignant glioma cells invade the surrounding brain parenchyma, by migrating along the blood vessels, thus promoting cancer growth. The biological bases of these activities are grounded in profound alterations of the metabolism and the structural organization of the cells, which consequently acquire the ability to modify the surrounding microenvironment, by altering the extracellular matrix and affecting the properties of the other cells present in the brain, such as normal glial-, endothelial- and immune-cells. Most of the effects on the surrounding environment are probably exerted through the release of a variety of extracellular vesicles (EVs), which contain many different classes of molecules, from genetic material to defined species of lipids and enzymes. EV-associated molecules can be either released into the extracellular matrix (ECM) and/or transferred to neighboring cells: as a consequence, both deep modifications of the recipient cell phenotype and digestion of ECM components are obtained, thus causing cancer propagation, as well as a general brain dysfunction. In this review, we first analyze the main intracellular and extracellular transformations required for glioma cell invasion into the brain parenchyma; then we discuss how these events may be attributed, at least in part, to EVs that, like the pawns of a dramatic chess game with cancer, open the way to the tumor cells themselves.