Downregulation of long non-coding RNA HCG11 predicts a poor prognosis in prostate cancer

LncRNA HCG11 enhances the chemosensitivity of non-small cell lung cancer cells to Gemcitabine via miR-17-5p/p21 axis

BACKGROUND

This study investigated the inhibitory effects of lncRNA HLA Complex Group 11 (HCG11) on non-small cell lung cancer (NSCLC) and the molecular mechanisms.

RESEARCH DESIGN AND METHODS

Bioinformatics analysis was conducted to determine the downstream targeted gene miR-17-5p/p21 and predict their binding sites. qRT-PCR and Western blot were used to detect expression levels, and dual luciferase and RIP assays were adopted to verify binding relationship.

RESULTS

The lncRNA HCG11/miR-17-5p/p21 axis was found to regulate drug resistance, proliferation, apoptosis, and cell cycle of A549 and A549-Gemcitabine (GEM) cells. HCG11 acted as a ceRNA binding to miR-17-5p, which repressed p21 expression in turn. In vivo experiments demonstrated that HCG11 hindered tumor growth. Therefore, lncRNA HCG11, by targeting the miR-17-5p/p21 axis, suppressed GEM resistance and malignant progression of NSCLC cells.

CONCLUSIONS

This study provides a reference for investigating the potential value of lncRNA HCG11 in the diagnosis of NSCLC and finding potential targets against clinical chemotherapeutic resistance in NSCLC.

LncRNA weighted gene co-expression network analysis reveals novel biomarkers related to prostate cancer metastasis

BACKGROUND

Most prostate cancer patients die from metastasis and lack accurate efficacious biomarkers to monitor the disease behavior, optimize treatment and assess prognosis. Herein, we aimed to identify meaningful lncRNA biomarkers associated with prostate cancer metastatic progression.

METHODS

By repurposing microarray probes, 11,624 lncRNAs in prostate cancer were obtained from Gene Expression Omnibus  database (GSE46691, N = 545; GSE29079, N = 235; GSE94767, N = 130). Weighted gene co-expression network analysis was applied to determine the co-expression lncRNA network pertinent to metastasis. Hub lncRNAs were screened. RNA-seq and clinical data from the Cancer Genome Atlas prostate cancer (TCGA-PRAD) cohort (N = 531) were analyzed. Transwell assay and bioinformatic analysis were performed for mechanism research.

RESULTS

The high expression levels of nine hub lncRNAs (FTX, AC005261.1, NORAD, LINC01578, AC004542.2, ZFAS1, EBLN3P, THUMPD3-AS1, GAS5) were significantly associated with Gleason score and increased probability of metastatic progression. Among these lncRNAs, ZFAS1 had the consistent trends of expression in all of the analysis from different cohorts, and the Kaplan-Meier survival analyses showed higher expression of ZFAS1 was associated with shorter relapse free survival. In-vitro studies confirmed that downregulation of ZFAS1 decreased prostate cancer cell migration.

CONCLUSION

We offered some new insights into discovering lncRNA markers correlated with metastatic progression of prostate cancer using the WGCNA. Some may serve as potential prognostic biomarkers and therapeutic targets for advanced metastatic prostate cancer.

Prostate cancer resistance leads to a global deregulation of translation factors and unconventional translation

Emerging evidence associates translation factors and regulators to tumorigenesis. However, our understanding of translational changes in cancer resistance is still limited. Here, we generated an enzalutamide-resistant prostate cancer (PCa) model, which recapitulated key features of clinical enzalutamide-resistant PCa. Using this model and poly(ribo)some profiling, we investigated global translation changes that occur during acquisition of PCa resistance. We found that enzalutamide-resistant cells exhibit an overall decrease in mRNA translation with a specific deregulation in the abundance of proteins involved in mitochondrial processes and in translational regulation. However, several mRNAs escape this translational downregulation and are nonetheless bound to heavy polysomes in enzalutamide-resistant cells suggesting active translation. Moreover, expressing these corresponding genes in enzalutamide-sensitive cells promotes resistance to enzalutamide treatment. We also found increased association of long non-coding RNAs (lncRNAs) with heavy polysomes in enzalutamide-resistant cells, suggesting that some lncRNAs are actively translated during enzalutamide resistance. Consistent with these findings, expressing the predicted coding sequences of known lncRNAs JPX, CRNDE and LINC00467 in enzalutamide-sensitive cells drove resistance to enzalutamide. Taken together, this suggests that aberrant translation of specific mRNAs and lncRNAs is a strong indicator of PCa enzalutamide resistance, which points towards novel therapeutic avenues that may target enzalutamide-resistant PCa.

Signaling Pathways and Targeted Therapies for Stem Cells in Prostate Cancer

Prostate cancer (PCa) is one of the most frequently occurring cancers among men, and the current statistics show that it is the second leading cause of cancer-related deaths among men. Over the years, research in PCa treatment and therapies has made many advances. Despite these efforts, the standardized therapies such as radiation, chemotherapy, hormonal therapy and surgery are not considered completely effective in treating advanced and metastatic PCa. In most situations, fast-dividing tumor cells are targeted, leaving behind relatively slowly dividing, chemoresistant cells known as cancer stem cells. Therefore, following the seemingly successful treatments, the lingering quiescent cancer stem cells are able to renew themselves, undergo differentiation into mature tumor cells, and sufficiently reinitiate the disease, leading to cancer relapse. Thus, prostate cancer stem cells (PCSCs) have been reported to play a vital role in controlling the dynamics of tumorigenesis, progression, and resistance to therapies in PCa. However, the complete knowledge on the mechanisms regulating the stemness of PCSCs is still unclear. Thus, studying the stemness of PCSCs will allow for the development of more effective cancer therapies due to the durable response, resulting in a reduction in recurrences of cancer. In this Review, we will specifically describe the molecular mechanisms responsible for regulating the stemness of PCSCs. Furthermore, current developments in stem cell-specific therapeutic approaches along with future prospects will also be discussed.

LncRNA HCG11 represses ovarian cancer cell growth via AKT signaling pathway

AIM

Ovarian cancer is a main contributor of cancer-relevant deaths among women worldwide due to high incidence and mortality. Mounting evidence has unveiled that lncRNAs play critical roles in malignancies, including ovarian cancer. Although the tumor suppressor function of HCG11 in prostate cancer and glioma has been proved, investigations on HCG11 role in ovarian cancer are still scarce.

METHODS

Gene or protein expression was quantified by RT-qPCR or western blot. HCG11 effects on ovarian cancer were assessed by functional assays. Bioinformatics analysis and mechanism experiments were implemented to identify the association among HCG11, miR-1270, and PTEN.

RESULTS

HCG11 was weakly expressed in ovarian cancer and functioned as a tumor suppressor in ovarian cancer by retarding cell proliferation, migration, and EMT. Besides, HCG11 could bind to miR-1270 and PTEN was a target gene of miR-1270. Mechanically, HCG11 competitively bound with miR-1270 to upregulate PTEN. From rescue experiments, HCG11 impeded AKT/mTOR pathway to retard ovarian cancer cell growth by miR-1270/PTEN.

CONCLUSIONS

HCG11 was a tumor suppressor in ovarian cancer cells and additionally, HCG11 regulated AKT/mTOR pathway to hinder ovarian cancer cell growth via modulating miR-1270/PTEN, indicating that HCG11 may represent a promising target for effective treatment of ovarian cancer patients.

Long non-coding RNA HCG11 enhances osteosarcoma phenotypes by sponging miR-1245b-5p that directly inhibits plakophilin 2

Long non-coding RNA (lncRNA) HCG11 can regulate various cancers through the ceRNA network. However, its role in osteosarcoma (OS) remains unknown. The HOS and Saos-2 cell lines were used for in vitro analyses. HCG11 and plakophilin 2 (PKP2) silencers, a miR-1245b-5p mimic, and a miR-1245b-5p inhibitor were utilized for the regulation analysis of lncRNA HCG11, miR-1245b-5p, and PKP2. Cell Counting Kit-8, wound healing, and transwell assays were used for cell proliferation, migration, and invasion analyses, and caspase-3 activity assay was used to measure cell apoptosis. The expression levels of lncRNA HCG11, miR-1245b-5p, and PKP2 were evaluated by quantitative real-time PCR and Western blotting. The distribution of lncRNA HCG11 was assessed using the RNA-FISH assay. The sponging and targeting roles of HCG11 and PKP2 on miR-1245b-5p were confirmed by dual-luciferase reporter analysis. An RNA immunoprecipitation assay was used to assess the binding between lncRNA HCG11 and miRNA-1245b-5p. We found that the lncRNA HCG11 was significantly upregulated in OS. LncRNA HCG11 silencing inhibits OS progression by repressing cell proliferation, migration, and invasion, and promoting cell apoptosis. RNA-FISH analysis indicated that lncRNA HCG11 was located in the cytoplasm. Mechanistic experiments showed that lncRNA HCG11 sponges miR-1245b-5p and negatively regulates miR-1245b-5p expression. Upregulated lncRNA HCG11 promotes proliferation, migration, and invasion, and inhibits apoptosis by inhibiting miR-1245b-5p in OS cells. PKP2 was verified as a target gene of miR-1245b-5p. Upregulated PKP2 promotes proliferation, migration, and invasion, and inhibits apoptosis by inhibiting miR-1245b-5p in OS. In conclusion, the HCG11/miR-1245b-5p/PKP2 axis promotes OS expression by promoting cell proliferation, migration, and invasion, and inhibiting apoptosis.

The role and mechanism of HLA complex group 11 in cancer

HLA is critical in a variety of diseases, including infectious disease and cancer, and has been used for diagnostic differentiation and immunosurveillance of certain diseases. In addition, emerging evidence suggests that the mutations and dysregulation of lncRNAs are essential contributors in cancers. HLA Complex Group 11 (HCG11) located on MHC region is affiliated with the lncRNA class. Studies have shown that HCG11 could serve as a key regulator in lung cancer, prostate cancer, glioma, cervical cancer and hepatocellular carcinoma. In this review, we summarize the accumulated information on the expression and clinical value of HCG11 in different cancer types, discuss its interactions with microRNAs, mRNAs, and proteins, and discover the biological roles and potential mechanisms of HCG11 in a variety of cellular functions, including cell proliferation, apoptosis, migration, and invasion. Further, we emphasize the possible application of HCG11 in treatment, summarize the studies of HCG11 in chemotherapy resistance and hormone therapy, and propose the significance of further study of HCG11.

LncRNA HCG11 promotes 5-FU resistance of colon cancer cells through reprogramming glucose metabolism by targeting the miR-144-3p-PDK4 axis

BACKGROUND

Colorectal cancer (CRC), one of the most common human malignancies, is a leading cause of the cancer-related mortality. 5-FU is a first-line chemotherapeutic agent against CRC. Although CRC patients responded to 5-FU therapy initially, a part of patients succumbed to CRC due to the acquired drug resistance. Thus, investigating molecular mechanisms underlying chemoresistance will contribute to developing novel strategies against colorectal cancer.

OBJECTIVE

Accumulation evidence revealed pivotal roles of long non-coding RNAs (lncRNAs) in tumorigenesis and chemoresistance of CRC. However, the precise roles and molecular mechanisms of lncRNA-HCG11 in CRC remain unclear. This study aimed to investigate the biological roles and underlying mechanisms of HCG11 as well as its molecular targets in regulating the cellular metabolism processes, which facilitate the chemoresistance of CRC.

METHODS AND RESULTS

This study uncovers that HCG11 was significantly upregulated in CRC tumors tissues and cell lines. Moreover, HCG11 was elevated in 5-FU resistant CRC tumors. Silencing HCG11 inhibited colon cancer cell proliferation, migration, invasion and glucose metabolism and sensitized CRC cells to 5-FU. In addition, we detected increased HCG11 expression level and glucose metabolism in the established 5-FU resistant CRC cell line (DLD-1 5-FU Res). Furthermore, microRNA-microArray, RNA pull-down and luciferase assays demonstrated that HCG11 inhibited miR-144-3p which displays suppressive roles in colon cancer via sponging it to form a ceRNA network. We identified pyruvate dehydrogenase kinase 4 (PDK4), which is a glucose metabolism key enzyme, was directly targeted by miR-144-3p in CRC cells. Rescue studies validated that the miR-144-3p-inhibited glucose metabolism and 5-FU sensitization were through targeting PDK4. Finally, restoration of miR-144-3p in HCG11-overexpressing DLD-1 5-FU resistant cells successfully overcame the HCG11-faciliated 5-FU resistance via targeting PDK4.

CONCLUSION

In summary, this study reveals critical roles and molecular mechanisms of the HCG11-mediated 5-FU resistance through modulating the miR-144-3p-PDK4-glucose metabolism pathway in CRC.

Long Noncoding RNA HCG9 Promotes Osteosarcoma Progression through RAD51 by Acting as a ceRNA of miR-34b-3p

Background

Long noncoding RNAs (lncRNAs) have critical regulatory functions in biological and pathological activities during osteosarcoma progression. It is important to elucidate the expression pattern and reveal the underlying mechanisms of the newly identified lncRNAs.

Methods

Herein, we screened the differentially expressed lncRNAs in osteosarcoma tumors and cell lines using lncRNA microarray. The candidate lncRNA was further verified by qRT-PCR, and the association of gene expression with clinicopathological features was evaluated by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. The targeting miRNA was identified using starBase analysis, and the competing endogenous RNA (ceRNA) network was established by STRING. Overexpression and silence of RNA were detected by qRT-PCR. Osteosarcoma cell proliferation was measured with CCK-8 assay, and the migration and invasion were evaluated with Transwell assay. Colony formation assay was observed. Flow cytometry evaluated the cell cycle. Western blot was performed to detect the mitotic markers and apoptosis-related proteins. A nude mouse tumor formation experiment was used to evaluate osteosarcoma progression in vivo. Cooverexpressing miR-34b-3p with RAD51 reversed the miR-34b-3p-induced changes in proliferation, the cell cycle, the expression of H2A.X, and that of apoptosis-related proteins.

Results

HCG9 was identified as osteosarcoma-associated lncRNA. Osteosarcoma tissues and cell lines expressed higher levels of HCG9 as compared to normal tissues and osteoblasts, and high expression of HCG9 was further proved to be related to metastasis and the grade of osteosarcoma in clinical cases. Knockdown of HCG9 inhibited the proliferation, migration, and invasion of osteosarcoma cells. miR-34b-3p was identified as the target of HCG9, and RAD51 acted as a potential target of miR-34b-3p. Cooverexpressing miR-34b-3p with HCG9 partially suppressed the HCG9-stimulated proliferation, migration, and invasion of osteosarcoma cells in vitro and delayed the tumor progression in vivo.

Conclusion

We discovered that lncRNA HCG9 promoted the proliferation of osteosarcoma cells via suppressing miR-34b-3p. Our study provides novel biomarkers and potential therapeutic targets for osteosarcoma treatment.

Long non‑coding RNA HCG11 suppresses the malignant phenotype of non‑small cell lung cancer cells by targeting a miR‑875/SATB2 axis

Long non‑coding RNAs (lncRNAs) are involved in the development and progression of a variety of diseases. However, the role of the lncRNA HLA complex group 11 (HCG11) in non‑small cell lung cancer (NSCLC) remains unclear. The present study showed that the expression levels of HCG11 were reduced in tumor tissues compared with adjacent normal tissues, and similar results were obtained in experiments using lung cancer cell lines. Additionally, patients with high HCG11 expression had an increased survival rate compared with patients with low HCG11 expression. Further studies have shown that overexpression of HCG11 inhibited NSCLC cell proliferation in vitro and in vivo. Interestingly, it was observed that HCG11 expression was negatively associated with the expression levels of oncogenic microRNA‑875 (miR‑875) in patient specimens. Specifically, HCG11 served as a sponge of miR‑875. Notably, it was determined that special AT‑rich sequence‑binding protein 2 (SATB2) was a direct target gene of miR‑875, and overexpression of miR‑875 largely abrogated the effects of HCG11 in NSCLC cells. In conclusion, HCG11 was shown to suppress the malignant properties of NSCLC cells by targeting a miR‑875/SATB2 axis, and may therefore be a promising target for the treatment of NSCLC.

LncRNA HCG11 Inhibits Adipocyte Differentiation in Human Adipose-Derived Mesenchymal Stem Cells by Sponging miR-204-5p to Upregulate SIRT1

Long noncoding RNAs (lncRNAs) have been discovered to play a key role in adipogenesis, while the role of lncRNA human leukocyte antigen complex group 11 (HCG11) in adipocyte differentiation has not been studied clearly. We used human adipose-derived mesenchymal stem cells (hAdMSCs) to establish a model of cell differentiation in vitro and found that expression of lncRNA HCG11 was decreased during adipogenesis through real-time quantitative polymerase chain reaction analysis. Then, hAdMSCs were transfected with pcDNA-HCG11 or HCG11-shRNA (sh-HCG11); the adipogenic marker proteins were detected by Western blot, and the activity of lipogenesis enzymes was detected by spectrophotometry. The expression of CCAAT-enhancer-binding protein α, fatty acid-binding protein, peroxisome proliferator-activated receptor gamma 2 and the levels of acetyl coenzyme A carboxylase and fatty acid synthase FAS were significantly downregulated in hAdMSCs at different stages transfected with pcDNA-HCG11, while knockdown of lncRNA HCG11 promoted adipocyte differentiation. Bioinformatic analysis indicated that miR-204-5p was a potential target gene of HCG11, which was confirmed by luciferase reporter gene analysis and RNA pull-down analysis. In addition, miR-204-5p directly targeting the 3′-untranslated region of SIRT1 was also predicted by StarBase and verified by luciferase reporter gene analysis. Enforced expression of miR-204-5p negatively regulated the SIRT1 protein level. Furthermore, SIRT1 overexpression significantly inhibited adipogenic marker protein, levels of lipogenesis enzymes, and the proliferation of hAdMSCs. When pcDNA-HCG11 and miR-204-5p mimic were co-transfected into hAdMSCs, we found that the miR-204-5p mimic reversed the suppressor effect of pcDNA-HCG11. Taken together, we found that HCG11 negatively regulated cell proliferation and adipogenesis by the miR-204-5p/SIRT1 axis. Our findings might provide a new target for the study of adipogenesis in hAdMSCs and obesity.

Long Noncoding RNA HCG11 Acts as a Tumor Suppressor in Gastric Cancer by Regulating miR-942-5p/BRMS1 Axis

The functions of long noncoding RNAs (lncRNAs) have been widely investigated in human cancers, including gastric cancer (GC). The purpose of this study was to elucidate the role of lncRNA HCG11 in GC. In this study, mRNA and protein expressions were detected by quantitative real-time polymerase chain reaction assays (RT-qPCR) and Western blot analysis. The proliferation ability of GC cells was examined by (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyl Tetrazolium Bromide) MTT assays. The invasion and migration abilities of GC cells were evaluated by Transwell assays. The binding sites between miR-942-5p and HCG11/BRMS1 were confirmed by dual-luciferase reporter assays. Results showed that LncRNA HCG11 was downregulated in GC cells. Functionally, overexpression of HCG11 inhibited GC cell proliferation, migration, and invasion. In addition, lncRNA HCG11 was found to act as a molecular sponge of miR-942-5p. Furthermore, miR-942-5p promoted GC progression by suppressing lncRNA HCG11 expression. Besides that, BRMS1 was confirmed as a direct target of miR-942-5p. More importantly, breast cancer metastasis suppressor 1 (BRMS1) inhibited GC progression by upregulating lncRNA HCG11 and downregulating miR-942-5p. In conclusion, LncRNA HCG11 inhibited cell proliferation, migration, and invasion in GC by sponging miR-942-5p and upregulating BRMS1.

Advancement and properties of circular RNAs in prostate cancer: An emerging and compelling frontier for discovering

Prostate cancer (PC) is the most common carcinoma among men worldwide which results in 26% of leading causes of cancer-related death. However, the ideal and effective molecular marker remains elusive. CircRNA, initially observed in plant-infected viruses and Sendai virus in 1979, is generated from pre-mRNA back-splicing and comes in to play by adequate expression. The differential expression in prostate tissues compared with the control reveals the promising capacity in modulating processes including carcinogenesis and metastasis. However, the biological mechanisms of regulatory network in PC needs to systemically concluded. In this review, we enlightened the comprehensive studies on the definite mechanisms of circRNAs affecting tumor progression and metastasis. What's more, we validated the potential clinical application of circRNAs serving as diagnostic and prognostic biomarker. The discussion and analysis in circRNAs will broaden our knowledge of the pathogenesis of PC and further optimize the current therapies against different condition.

Long Non-Coding RNA HCG11 Aggravates Osteosarcoma Carcinogenesis via Regulating the microRNA-579/MMP13 Axis

Background

Previous studies have suggested that long non-coding RNAs (lncRNAs) were involved in tumorigenesis of various human carcinomas, including osteosarcoma (OS). However, the expression and specific role of lncRNA HLA complex group 11 (HCG11) in OS remain unknown. The current study aimed at revealing the role of lncRNA HCG11 and its related mechanism in OS.

Methods

lncRNA HCG11 expression was verified with RT-qPCR followed by sub-localization determination. LncRNA-microRNA (miRNA) and miRNA–mRNA interactions were predicted by online bioinformatics websites. Validation was performed using dual-luciferase reporter gene assays, and gain- and loss-of-function experiments. The effects of lncRNA HCG11, miR-579 and matrix metalloproteinase 13 (MMP13) on the proliferation, migration and invasion, epithelial-mesenchymal transition (EMT) of OS cells were detected using cell counting kit-8 (CCK-8), Transwell assays and Western blot analysis.

Results

LncRNA HCG11 overexpression was observed in OS tissues and cell lines. Downregulation of lncRNA HCG11/MMP13 or overexpression of miR-579 blocked the progression of OS cells. LncRNA HCG11, which is located in the cytoplasm, promoted MMP13 expression through sponging miR-579.

Conclusion

LncRNA HCG11 might be beneficial for OS aggravation via sponging miR-579 and facilitating MMP13 expression, which represents a candidate biomarker and target for OS therapy.

LncRNA HCG11/miR-26b-5p/QKI5 feedback loop reversed high glucose-induced proliferation and angiogenesis inhibition of HUVECs

Acute coronary syndrome caused by the rupture of atherosclerotic plaques is one of the primary causes of cerebrovascular and cardiovascular events. Neovascularization within the plaque is closely associated with its stability. Long non-coding RNA (lncRNA) serves a crucial role in regulating vascular endothelial cells (VECs) proliferation and angiogenesis. In this study, we identified lncRNA HCG11, which is highly expressed in patients with vulnerable plaque compared with stable plaque. Then, functional experiments showed that HCG11 reversed high glucose-induced vascular endothelial injury through increased cell proliferation and tube formation. Meanwhile, vascular-related RNA-binding protein QKI5 was greatly activated. Luciferase reporter assays and RNA-binding protein immunoprecipitation (RIP) assays verified interaction between them. Interestingly, HCG11 can also positively regulated by QKI5. Bioinformatics analysis and luciferase reporter assays showed HCG11 can worked as a competing endogenous RNA by sponging miR-26b-5p, and QKI5 was speculated as the target of miR-26b-5p. Taken together, our findings revered that the feedback loop of lncRNA HCG11/miR-26b-5p/QKI-5 played a vital role in the physiological function of HUVECs, and this also provide a potential target for therapeutic strategies of As.

Long non-coding RNA NORAD contributes to the proliferation, invasion and EMT progression of prostate cancer via the miR-30a-5p/RAB11A/WNT/β-catenin pathway

Background

Prostate cancer (PC) is common male cancer with high mortality worldwide. Emerging evidence demonstrated that long noncoding RNAs (lncRNAs) play critical roles in various type of cancers including PC by serving as competing endogenous RNAs (ceRNAs) to modulate microRNAs (miRNAs). LncRNA activated by DNA damage (NORAD) was found to be upregulated in PC cells, while the detailed function and regulatory mechanism of NORAD in PC progression remains largely unclear.

Methods

Expression of NORAD in PC tissues and cell lines were detected by real-time quantitative PCR (qRT-PCR). NORAD was respectively overexpressed and knocked down by transfection with pcDNA-NORAD and NORAD siRNA into PC-3 and LNCap cells. Cell proliferation, invasion and apoptosis were determined by using CCK-8, Transwell and Flow cytometry assays, respectively. The target correlations between miR-30-5p and NORAD or RAB11A were confirmed by using dual luciferase reporter assay. Moreover, expression levels of RAB11A, the epithelial-mesenchymal transition (EMT) marker proteins and the Wnt pathway related proteins were measured by Western blotting. Tumor xenograft assay was used to study the effect of NORAD on tumor growth in vivo.

Results

NORAD was upregulated in PC tissues and cells. Overexpression of NORAD promoted cell proliferation, invasion, EMT, and inhibited cell apoptosis; while knockdown of NORAD had the opposite effect. NORAD was found to be functioned as a ceRNA to bind and downregulated miR-30a-5p that was downregulated in PC tumor tissues. Rescue experiments revealed that miR-30a-5p could weaken the NORAD-mediated promoting effects on cell proliferation, invasion and EMT. Furthermore, RAB11A that belongs to a member of RAS oncogene family was verified as a target of miR-30a-5p, and reintroduction of RAB11A attenuated the effects of miR-30a-5p overexpression on cell proliferation, invasion, EMT and apoptosis of PC cells. More importantly, silencing RAB11A partially reversed the promoting effects of NORAD overexpression on cell proliferation, invasion and EMT of PC cells via the WNT/β-catenin pathway. Lastly, tumorigenicity assay in vivo demonstrated that NORAD increased tumor volume and weight via miR-30a-5p /RAB11A pathway.

Conclusion

Our results indicated a significant role of NORAD in mechanisms associated with PC progression. NORAD promoted cell proliferation, invasion and EMT via the miR-30a-5p/RAB11A/WNT/β-catenin pathway, thus inducing PC tumor growth.

Down-regulation of lncRNA HCG11 promotes cell proliferation of oral squamous cell carcinoma through sponging miR-455-5p

BACKGROUND

As a type of head and neck squamous cell carcinoma (HNSCC), oral squamous cell carcinoma (OSCC) has a high incidence and low survival rate. Frequent deletion of protein tyrosine phosphatase receptor type sigma (PTPRS) has been found in HNSCC. Long non-coding RNA (lncRNA) HCG11 and miR-455-5p have been reported to be involved in several cancers, in which miR-455-5p was found to be up-regulated in the OSCC. However, the role of HCG11 in OSCC development is still unclear.

METHODS

Several co-transfection systems were established to explore the regulation of HCG11 on OSCC cells. Cell proliferation was evaluated by the MTT assay, flow cytometry of cell cycle distribution, immunofluorescence of Ki67 and western blotting. A dual luciferase reporter assay was performed to verify the binding effects of miR-455-5p on HCG11 and PTPRS. The role of HCG11 knockdown in OSCC cell growth was also confirmed by nude mouse tumorigenicity assay in vivo.

RESULTS

Knockdown of HCG11 increased OSCC cell proliferation, as indicated by enhanced cell vitalities over time, increased G1/S transition and Ki67 levels. Furthermore, lncRNA HCG11 was shown to negatively regulate miR-455-5p and miR-455-5p targeted PTPRS directly to affect its downstream indicators, which can further modulate OSCC cell proliferation and growth. The results obtained in vivo confirmed that HCG11 knockdown promoted OSCC cell growth.

CONCLUSIONS

The lncRNA HCG11/miR-R-455-5p axis can be considered as an upstream signalling circuit of PTPRS with respect to regulating its activity and downstream pathways to further influence the progression of OSCC. This finding may provide a novel RNA-based therapeutic target for OSCC treatment.

Lung Carcinoma Cells Secrete Exosomal MALAT1 to Inhibit Dendritic Cell Phagocytosis, Inflammatory Response, Costimulatory Molecule Expression and Promote Dendritic Cell Autophagy via AKT/mTOR Pathway

Objective

To investigate the potential mechanism underlying the effect of lung carcinoma cell-derived exosomes on dendritic cell function.

Materials and Methods

C57BL/6 (B6) mice were randomly divided into five groups: control, dendritic cell (DC), DC-NC, DC-siMALAT1, and siMALAT1. Tumor cell proliferation was measured by Ki-67 staining. LLC cells were divided into control, NC, and si-MALAT1 groups, and exosomes secreted by each group were labeled as PEX, PEXN, and PEX-si, respectively. Exosomes and autophagic vacuoles were observed by transmission electron microscopy. MALAT1 expression in LLC, A549, and Beas-2b cells was examined by RT-PCR. The expression of IFN-γ, IL-12, IL-10, and TGF-β was observed by Elisa assay. Flow cytometry was used to observe the phagocytic function of DCs, costimulatory molecule expression, and T cell proliferation and differentiation. The protein expression of p-AKT, AKT, p-mTOR, mTOR, ALIX, TSG101, and CD63 was detected by Western blot.

Results

Compared with Beas-2b cells, MALAT1 expression was significantly increased in both LLC and A549 cells and in their secreted exosomes, and LLC cells showed the highest expression of MALAT1 (P < 0.05). Tumor cell proliferation and tumor volume were significantly decreased in the siMALAT1 and DC-siMALAT1 groups compared to those in the control group. DC phagocytosis, inflammatory response, costimulatory molecule expression, and T cell proliferation in the siMALAT1 and PEX-si groups were significantly enhanced (P < 0.05), while DC autophagy and T cell differentiation were reduced (P < 0.05). The levels of p-AKT, AKT, p-mTOR, and mTOR in the PEX and PEXN groups were increased compared with those in the control group, while those in the siMALAT1 and PEX-si groups were significantly decreased (P < 0.05).

Conclusion

Inhibition of MALAT1 expression in LLC-derived exosomes promoted DC function and T cell proliferation and suppressed DC autophagy and T cell differentiation, suggesting that MALAT1 inhibition may be a potential strategy for the clinical treatment of lung cancer.

LncRNA HCG11 regulates proliferation and apoptosis of vascular smooth muscle cell through targeting miR-144-3p/FOXF1 axis in atherosclerosis

BACKGROUND

Atherosclerosis (AS) is the main pathological basis of coronary heart disease, cerebral infarction and peripheral vascular disease, which seriously endanger people's life and health. In recent years, long non-coding RNA (lncRNA) has been found to be involved in gene expression regulation, but the research on AS is still in the initial stage. In this study, we mainly studied the role of HCG11 in patients with AS. Quantitative Real-time Polymerase Chain Reaction (QRT-PCR) was used to detect the expression of HCG11 and miR-144 in the serum of AS patients and healthy volunteers. Oxidation Low Lipoprotein (Ox-LDL), interleukin-6 (IL-6) and tumor necrosis factor α (TNF α) radiation were used to establish human vascular smooth muscle cells (VSMCs) in vitro model. Cell proliferation was determined by Cell Counting Kit-8 (CCK-8) assay. The apoptosis rate was determined by flow cytometry (FACS) and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL) staining. The expression levels of Forkhead box protein F1 (FOXF1), B cell lymphoma-2 (Bcl-2) and BCL2-Associated X (Bax) were detected by qRT-PCR. Luciferase gene reporter and RNA pull down experiments confirmed the relationship between HCG11 and miR-144, miR-144 and FOXF1.

RESULTS

This study showed that HCG11 was significantly upregulated in patients with AS, while miR-144 was down-regulated in patients with AS. Ox-LDL and IL-6 in VSMCs induced up-regulation of HCG11 and down-regulation of miR-144. Overexpression of HCG11 promoted the proliferation and inhibited apoptosis of VSMCs. Luciferase gene reporter gene assay showed that HCG11 could bind to miR-144, and miR-144 could bind to FOXF1. Overexpression of miR-144 reversed the effect of HCG11 on VSMCs.

CONCLUSIONS

LncRNA HCG11 regulates proliferation and apoptosis of vascular smooth muscle cell through targeting miR-144-3p/FOXF1 axis.

Long non-coding RNA HCG11 sponging miR-522-3p inhibits the tumorigenesis of non-small cell lung cancer by upregulating SOCS5

BACKGROUND

Numerous studies have shown that long non-coding RNA (lncRNA) is involved in various human diseases including non-small cell lung cancer (NSCLC). The aim of this study was to explore the potential role of lncRNA HCG11 in the pathogenesis of NSCLC.

METHODS

The mRNA expression of HCG11, miR-522-3p and SOCS5 was detected by RT-qPCR. The regulatory mechanism of lncRNA HCG11 was investigated by CCK-8, transwell and dual luciferase reporter assays.

RESULTS

Downregulation of lncRNA HCG11 and upregulation of miR-522-3p were found in NSCLC tissues and cells, and abnormal expressions of lncRNA HCG11 and miR-522-3p were related to adverse clinical outcomes of NSCLC patients. LncRNA HCG11 acted as a molecular sponge for miR-522-3p. Functionally, lncRNA HCG11 inhibited cell viability, migration and invasion in NSCLC by downregulating miR-522-3p. Further, miR-522-3p directly targeted SOCS5. lncRNA HCG11 could positively regulate SOCS5 expression in NSCLC. In addition, HCG11 downregulation or miR-522-3p overexpression abolished the inhibitory effect of SOCS5 on cell viability, migration and invasion in NSCLC.

CONCLUSIONS

LncRNA HCG11 inhibits cell viability, migration and invasion in NSCLC by functioning as a ceRNA of miR-522-3p to upregulate SOCS5.

Recent scenario of long non-coding RNAs as a diagnostic and prognostic biomarkers of prostate cancer

Prostate cancer (CaP) is a leading cause of cancer deaths in the worldwide with broad range of clinical manifestations ranging from relatively indolent to aggressive metastasis. Altered expression of many circulating long non-coding RNAs (lncRNAs), known to have role in tumorigenesis and metastasis, have already been reported in CaP patients. These lncRNAs modulate CaP pathogenesis by modulating multiple genes and thus altering metabolic pathways. Sustained androgen receptor (AR) signaling is one such key feature of castration-resistant prostate cancer, a CaP stage that has unmet need of accurate diagnostic and prognostic tools, that is affected by lncRNAs. In this review, we have discussed the emerging functions and associations of AR lncRNAs in CaP and highlighted their potential implications in cancer diagnostics and therapeutics. Further, extensive literature analysis in this article indicates that there is an immediate unmet need in the translational approach toward the hitherto identified AR lncRNAs. The characterization of AR lncRNAs involved in CaP is not exhaustive and adequate validation studies are still required to corroborate the present results that would be the impending future of basic research setting into clinical practice.

LncRNA HCG11 Suppresses Cell Proliferation and Promotes Apoptosis via Sponging miR-224-3p in Non-Small-Cell Lung Cancer Cells

INTRODUCTION

Studies have found that Lnc-HCG11 is an important regulator of cancer. However, the function of Lnc-HCG11 in NSCLC is not known. Therefore, this experimental design was based on Lnc-HCG11 to explore the pathogenesis of NSCLC.

METHODS

RT-qPCR was used to detect the expression of Lnc-HCG11 and miR-224-3p in NSCLC. The effects of Lnc-HCG11 and miR-224-3p on proliferation and apoptosis of NSCLC cells were detected by CCK-8 assay, Edu assay and Annexin V-FITC/PI assay. Target gene prediction and screening, luciferase reporter assays were used to verify downstream target genes for lnc-HCG11 and miR-224-3p. Western blotting was used to detect the protein expression of caspase-3. The tumor changes in mice were detected by in vivo.

RESULTS

Lnc-HCG11 was significantly reduced in NSCLC. Lnc-HCG11 significantly inhibited cell proliferation of NSCLC cells and induced apoptosis. miR-224-3p was significantly elevated in the NSCLC cell line. Moreover, miR-224-3p significantly increased cell proliferation and inhibited apoptosis of NSCLC cells. Furthermore, Lnc-HCG11 was negatively correlated with miR-224-3p expression. Lnc-HCG11 over-expression was up-regulated the expression levels of c-caspase-3 and caspase-3. Finally, the results of in vivo animal models confirmed that Lnc-HCG11 inhibited tumor growth by modulating the miR-224-3p/c-caspase-3 axis.

CONCLUSION

Lnc-HCG11 could inhibit the progression of NSCLC by modulating the miR-224-3p/caspase-3 axis, and Lnc-HCG11 may be a potential therapeutic target for NSCLC.

Long non-coding RNA profiling of pediatric Medulloblastoma

Background

Medulloblastoma (MB) is one of the most common malignant cancers in children. MB is primarily classified into four subgroups based on molecular and clinical characteristics as (1) WNT (2) Sonic-hedgehog (SHH) (3) Group 3 (4) Group 4. Molecular characteristics used for MB classification are based on genomic and mRNAs profiles. MB subgroups share genomic and mRNA profiles and require multiple molecular markers for differentiation from each other. Long non-coding RNAs (lncRNAs) are more than 200 nucleotide long RNAs and primarily involve in gene regulation at epigenetic and post-transcriptional levels. LncRNAs have been recognized as diagnostic and prognostic markers in several cancers. However, the lncRNA expression profile of MB is unknown.

Methods

We used the publicly available gene expression datasets for the profiling of lncRNA expression across MB subgroups. Functional analysis of differentially expressed lncRNAs was accomplished by Ingenuity pathway analysis (IPA).

Results

In the current study, we have identified and validated the lncRNA expression profile across pediatric MB subgroups and associated molecular pathways. We have also identified the prognostic significance of lncRNAs and unique lncRNAs associated with each MB subgroup.

Conclusions

Identified lncRNAs can be used as single biomarkers for molecular identification of MB subgroups that warrant further investigation and functional validation.

In silico identification of MAPK14-related lncRNAs and assessment of their expression in breast cancer samples

Mitogen-activated protein kinase (MAP kinase) pathways participate in regulation of several cellular processes involved in breast carcinogenesis. A number of non-coding RNAs including both microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) regulate or being regulated by MAPKs. We performed an in-silico method for identification of MAPKs with high number of interactions with miRNAs and lncRNAs. Bioinformatics approaches revealed that MAPK14 ranked first among MAPKs. Subsequently, we identified miRNAs and lncRNAs that were predicted to be associated with MAPK14. Finally, we selected four lncRNAs with higher predicted scores (NORAD, HCG11, ZNRD1ASP and TTN-AS1) and assessed their expression in 80 breast cancer tissues and their adjacent non-cancerous tissues (ANCTs). Expressions of HCG11 and ZNRD1ASP were lower in tumoral tissues compared with ANCTs (P values < 0.0001). However, expression levels of MAPK14 and NORAD were not significantly different between breast cancer tissues and ANCTs. A significant association was detected between expression of HCG11 and estrogen receptor (ER) status in a way that tumors with up-regulation of this lncRNA were mostly ER negative (P value = 0.04). Expressions of ZNRD1ASP and HCG11 were associated with menopause age and breast feeding duration respectively (P values = 0.02 and 0.04 respectively). There was a trend towards association between ZNRD1ASP expression and patients' age of cancer diagnosis. Finally, we detected a trend toward association between expression of NORAD and history of hormone replacement therapy (P value = 0.06). Expression of MAPK14 was significantly higher in grade 1 tumors compared with grade 2 tumors (P value = 0.02). Consequently, the current study provides evidences for association between lncRNA expressions and reproductive factors or tumor features.

A 14-Methylation-Driven Differentially Expressed RNA as a Signature for Overall Survival Prediction in Patients with Uterine Corpus Endometrial Carcinoma

DNA methylation has been implicated as an important mechanism for the development of uterine corpus endometrial carcinoma (UCEC), indicating that methylation-driven genes may be potential biomarkers for survival prediction. In this study, we aimed to identify a new prognostic methylation signature for UCEC based on differentially expressed genes (DEGs) and long noncoding RNAs (lncRNAs) (DELs). Sample-matched RNA-sequencing and methylation-array data were downloaded from The Cancer Genome Atlas database, by analysis of which a total of 269 DEGs and 4 DELs were identified to be methylation driven. Least absolute shrinkage and selection operator analysis screened that 14 methylation-driven genes were significantly associated with overall survival (OS) and thus were used as a signature to establish a prognostic risk model. Based on the median threshold, the patients were divided into the low-risk and the high-risk groups, which showed significantly different survival periods under the Kaplan-Meier curve. The area under receiver operating characteristic curve (AUC) was 0.934, 0.919, and 0.952 for the training, validation, and entire cohort, respectively. Stratification analysis showed that the established risk model may add prognostic values to conventional clinical factors (age, neoplasm histologic grade, and clinical stage). A nomogram was constructed based on the risk model and clinical parameters, with the AUC of 0.978 and c-index of 0.8079. Database for Annotation, Visualization, and Integrated Discovery (DAVID) function enrichment and Human Protein Atlas (HPA) protein expression validation showed 5 of these 14 genes may be especially important for UCEC (hypermethylated lowly expressed: CCBE1, FOXL2, PHLDB2, and DTNA; hypomethylated highly expressed: CCNE1). Comparison with breast cancer in the methylation level indicated ABCA12, CCNE1, and CLRN3 may be specific methylation-driven genes for UCEC. LncRNA HCG11 may function by coexpressing with DTNA. In conclusion, this 14-DNA methylation signature combined with clinical factors may a potentially effective biomarker in predicting OS for UCEC patients.

A comprehensive review of the role of long non-coding RNAs in organs with an endocrine function

Long non-coding RNAs (lncRNAs) are transcripts with sizes larger than 200 nucleotides and no/ small open reading frame that cannot produce functional proteins. The number of these transcripts surpasses the number of coding genes. LncRNAs regulate many aspects of cell functions such as proliferation, cell cycle transition and differentiation; so their dysregulation has pervasive effects on cell phenotype. Increasing numbers of these transcripts have been shown to participate in the pathogenesis of cancer. In the current review, we summarize recent findings regarding the role of lncRNAs in tumors originated from organs which have an endocrine function. We mostly focused on adrenal, pancreas and pituitary gland as prototypes of these organs. Moreover, we presented the obtained data of the role of lncRNAs in prostate, ovarian and testicular cancers. Recent data highly supports the role of lncRNAs in the pathogenesis of cancers originated from these organs. Moreover, certain genomic loci within lncRNAs have been shown to be associated with risk of these cancers. Diagnostic and prognostic role of some lncRNAs in these cancers have been evaluated recently. Taken together, lncRNAs are putative biomarkers for cancers originated from organs which have an endocrine function.

Identification of Potential Prognostic Long Non-Coding RNA Biomarkers for Predicting Recurrence in Patients with Cervical Cancer

Background

Cervical cancer (CC) is one of the most common malignant tumors in women, and its treatment is often accompanied by high recurrence. We aimed to identify the long non-coding RNAs (lncRNAs) associated with CC recurrence.

Methods

We downloaded lncRNAs expression data of CC patients from The Cancer Genome Atlas (TCGA) dataset and used Cox regression models to analyze the lncRNAs relationship with CC recurrence. The significantly associated lncRNAs were utilized to construct a recurrence risk score (RRS) model. Bioinformatics analyses were used to assess the potential role of the critical lncRNAs in CC recurrence. The effect of critical lncRNAs on CC phenotype was determined by in vitro experiments.

Results

Using Cox regression analysis, four lncRNAs, ie, HCG11, CASC15, LINC00189, and LINC00905, were markedly associated with worse recurrence-free survival (RFS) of CC, whereas three lncRNAs, including HULC, LINC00173, and MIR22HG, were the opposite. After constructing the RRS model, Kaplan-Meier analysis revealed that patients with high RRS had significantly increased risk of recurrence. Among the 20 types of tumors in the TCGA database which all had adjacent normal tissues, MIR22HG and HCG11were significantly downregulated in 18 and 10 types of tumors including CC, respectively. Increased MIR22HG was significantly relevant to decreased risks of recurrence among the subgroups of age at diagnosis < 45 (Hazard Ratio (HR) = 0.26), stage I/II (HR = 0.33), T stage I/II (HR = 0.30), chemotherapy (HR = 0.18), and molecular therapy (HR = 0.16). Functionally, elevated MIR22HG expression could suppress CC cell proliferation, migration and invasion.

Conclusion

MIR22HG has a fundamental role in CC recurrence and could be served as a potential prognostic biomarker.

LINC00908 negatively regulates microRNA-483-5p to increase TSPYL5 expression and inhibit the development of prostate cancer

Background

Accumulating evidence has associated aberrant long non-coding RNAs (lncRNAs) with various human cancers. This study aimed to explore the role of LINC00908 in prostate cancer (PCa) and its possible underlying mechanisms.

Methods

Microarray data associated with PCa were obtained from the Gene Expression Omnibus (GEO) to screen the differentially expressed genes or lncRNAs. Then, the expression of LINC00908 in PCa tissues and cell lines was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The localization of LINC00908 in PCa cells was examined by fluorescence in situ hybridization (FISH). The relationship among LINC00908, microRNA (miR)-483-5p, and TSPYL5 was detected by bioinformatics analysis, dual-luciferase reporter assay, RNA pull-down, RNA binding protein immunoprecipitation (RIP), and FISH assays. Cell biological behaviors were assessed after the expression of LINC00908, miR-483-5p, and TSPYL5 was altered in PCa cells. Lastly, tumor growth in nude mice was evaluated.

Results

Poorly expressed LINC00908 was witnessed in PCa tissues and cells. LINC00908 competitively bound to miR-483-5p to up-regulate the TSPYL5 expression. Overexpression of LINC00908 resulted in reduced PCa cell proliferation, migration and invasion, and promoted apoptosis. Additionally, the suppression on PCa cell proliferation, migration and invasion was induced by up-regulation of TSPYL5 or inhibition of miR-483-5p. In addition, in vivo experiments showed that overexpression of LINC00908 inhibited tumor growth of PCa.

Conclusion

Overall, LINC00908 could competitively bind to miR-483-5p to increase the expression of TSPYL5, thereby inhibiting the progression of PCa. Therefore, LINC00908 may serve as a novel target for the treatment of PCa.

lncRNA HCG11 regulates cell progression by targeting miR-543 and regulating AKT/mTOR pathway in prostate cancer

Prostate cancer (PCa) is a common cancer worldwide, which mostly occurs in males over the age of 50. Accumulating evidence have determined that long non-coding RNA/microRNA (lncRNA/miRNA) axis plays a critical role in cell progression of cancers, including PCa. However, the pathogenesis of PCa has not been fully indicated. In this study, quantitative real-time polymerase chain reaction was used to detect the expression of HCG11 and miR-543. Western blot was applied to measure the protein expression of proliferating cell nuclear antigen, cleavage-caspase 3 (cle-caspase 3), N-cadherin, E-cadherin, GAPDH, P-AKT, AKT, p-mTOR, and mTOR. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), transwell invasion, and transwell migration assay were used to detect cell proliferation, invasion, and migration, respectively. The function and mechanism of lncRNA HCG11 were confirmed in PCa cell and xenograft mice models. Luciferase assay indicated that miR-543 was a target miRNA of HCG11. Further investigation revealed that overexpression of HCG11 inhibited cell proliferation, invasion, and migration, whereas induced cell apoptosis by regulating miR-543 expression in vitro and in vivo. More than that, lncRNA HCG11 inhibited phosphoinositide-3 kinase/protein kinaseB (PI3K/AKT) signaling pathway to suppress PCa progression. Our data showed the overexpression of HGC11-inhibited PI3K/AKT signaling pathway by downregulating miR-543 expression, resulting in the suppression of cell growth in PCa. This finding proved a new regulatory network in PCa and provided a novel therapeutic target of PCa.

A novel androgen-reduced prostate-specific lncRNA, PSLNR, inhibits prostate-cancer progression in part by regulating the p53-dependent pathway

BACKGROUND

Prostate cancer (PCa) is one of the most common cancers in males in China. Long noncoding RNAs (lncRNAs) reportedly play crucial roles in human cancer progression in many studies. However, the molecular mechanisms underlying PCa progression remain unclear.

MATERIALS AND METHODS

We investigated the lncRNA transcriptome using publicly available RNA-sequencing data to identify prostate-specific lncRNAs. Then, the chromatin immunoprecipitation (ChIP) assay identified lncRNA with a direct binding to androgen receptor (AR), hereafter denoted as PSLNR. Quantitative real-time polymerase chain reaction analysis and Western blot analysis were performed to detect the expression of p53 signaling-related genes after overexpression PSLNR. The effects of overexpression of PSLNR on cell proliferation, cell cycle, and cell apoptosis were assessed by using CCK-8 and flow cytometric analysis. We then detected the expression of PSLNR in tissues.

RESULT

We reported a novel androgen-reduced prostate-specific lncRNA, PSLNR, that inhibited PCa progression via the p53-dependent pathway. By analyzing the NOCODE data set, we reported that PSLNR was specifically expressed in the prostate, suggesting the potential of PSLNR as a biomarker for PCa treatment. The AR pathway was also confirmed to be an upstream regulation signaling pathway of PSLNR by transcriptionally regulating its expression in androgen-dependent PCa cells. PSLNR also significantly inhibited PCa proliferation by inducing cell apoptosis in a p53-dependent manner. Thus, PSLNR may be a candidate diagnosis and therapeutic target for PCa.

CONCLUSIONS

Our study revealed for the first time a novel androgen-reduced prostate-specific lncRNA, PSLNR, which inhibited PCa progression via the p53-dependent pathway, suggesting that PSLNR may be a candidate diagnosis and therapeutic target for PCa.

Long non-coding RNAs in prostate cancer: Functional roles and clinical implications

Long noncoding RNAs (lncRNAs) are defined as RNA transcripts longer than 200 nucleotides that do not encode proteins. LncRNAs have been documented to exhibit aberrant expression in various types of cancer, including prostate cancer. Currently, screening for prostate cancer results in overdiagnosis. The consequent overtreatment of patients with indolent disease in the clinic is due to the lack of appropriately sensitive and specific biomarkers. Thus, the identification of lncRNAs as novel biomarkers and therapeutic targets for prostate cancer is promising. In the present review, we attempt to summarize the current knowledge of lncRNA expression patterns and mechanisms in prostate cancer. In particular, we focus on lncRNAs regulated by the androgen receptor and the specific molecular mechanism of lncRNAs in prostate cancer to provide a potential clinical therapeutic strategy for prostate cancer.

Long non-coding RNA HCG11 modulates glioma progression through cooperating with miR-496/CPEB3 axis

Objectives

It has been widely reported that long non‐coding RNAs (lncRNAs) can participate in multiple biological processes of human cancers. lncRNA HLA complex group 11 (HCG11) has been reported in human cancers as a tumour suppressor. This study focused on investigating the function and mechanism of HCG11 in glioma.

Materials and methods

Based on The Cancer Genome Atlas (TCGA) data set and qRT‐PCR analysis, the expression pattern of HCG11 was identified in glioma samples. The mechanism associated with HCG11 downregulation was determined by mechanism experiments. Gain‐of‐function assays were conducted for the identification of HCG11 function in glioma progression. Mechanism investigation based on the luciferase reporter assay, RIP assay and pull‐down assay was used to explore the downstream molecular mechanism of HCG11. The role of molecular pathway in the progression of glioma was analysed in accordance with the rescue assays.

Results

HCG11 was expressed at low level in glioma samples compared with normal samples. FOXP1 could bind with HCG11 and transcriptionally inactivated HCG11. Overexpression of HCG11 efficiently suppressed cell proliferation, induced cell cycle arrest and promoted cell apoptosis. HCG11 was predominantly enriched in the cytoplasm of glioma cells and acted as a competing endogenous RNAs (ceRNAs) by sponging micro‐496 to upregulate cytoplasmic polyadenylation element binding protein 3 (CPEB3). CEPB3 and miR‐496 involved in HCG11‐mediated glioma progression.

Conclusions

HCG11 inhibited glioma progression by regulating miR‐496/CPEB3 axis.

Comprehensive analysis of differentially expressed long non-coding RNAs in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the primary subtype of lung cancer. Long non-coding RNAs (lncRNAs) have been reported to serve prominent roles in cancer progression. However, the expression patterns and potential roles of lncRNAs in NSCLC remain to be elucidated. In the present study, four public datasets were analyzed to identify differentially expressed lncRNAs (DElncs) in NSCLC. A further dataset, GSE19188, was analyzed to validate the findings. A total of 38 upregulated and 31 downregulated lncRNAs were identified in NSCLC, compared with samples from healthy controls. Among these, 12 lncRNAs were associated with the progression of NSCLC, and dysregulated between high grade (stage III and IV) and low grade (stage II) NSCLC samples. Moreover, dysregulation of lncRNA-SIGLEC17P, GGTA1P, A2M-AS1, LINC00938, GVINP1, LINC00667 and TMPO-AS1 was associated with overall survival time in patients with NSCLC. Co-expression analyses, combined with the construction of protein-protein interaction networks, were performed to reveal the potential roles of key lncRNAs in NSCLC. The present study revealed a series of lncRNAs involved in the progression of NSCLS, which may serve as novel biomarkers for the disease.

Aberrant Expression of Pseudogene-Derived lncRNAs as an Alternative Mechanism of Cancer Gene Regulation in Lung Adenocarcinoma

Transcriptome sequencing has led to the widespread identification of long non-coding RNAs (lncRNAs). Subsequently, these genes have been shown to hold functional importance in human cellular biology, which can be exploited by tumors to drive the hallmarks of cancer. Due to the complex tertiary structure and unknown binding motifs of lncRNAs, there is a growing disparity between the number of lncRNAs identified and those that have been functionally characterized. As such, lncRNAs deregulated in cancer may represent critical components of cancer pathways that could serve as novel therapeutic intervention points. Pseudogenes are non-coding DNA sequences that are defunct relatives of their protein-coding parent genes but retain high sequence similarity. Interestingly, certain lncRNAs expressed from pseudogene loci have been shown to regulate the protein-coding parent genes of these pseudogenes in trans particularly because of this sequence complementarity. We hypothesize that this phenomenon occurs more broadly than previously realized, and that aberrant expression of lncRNAs overlapping pseudogene loci provides an alternative mechanism of cancer gene deregulation. Using RNA-sequencing data from two cohorts of lung adenocarcinoma, each paired with patient-matched non-malignant lung samples, we discovered 104 deregulated pseudogene-derived lncRNAs. Remarkably, many of these deregulated lncRNAs (i) were expressed from the loci of pseudogenes related to known cancer genes, (ii) had expression that significantly correlated with protein-coding parent gene expression, and (iii) had lncRNA protein-coding parent gene expression that was significantly associated with survival. Here, we uncover evidence to suggest the lncRNA-pseudogene-protein-coding gene axis as a prominent mechanism of cancer gene regulation in lung adenocarcinoma, and highlights the clinical utility of exploring the non-coding regions of the cancer transcriptome.

Long non-coding RNA HCG11 suppresses the growth of glioma by cooperating with the miR-4425/MTA3 axis

BACKGROUND

Glioma is a type of malignant tumor that occurs in the central nervous system of adults. Long non-coding RNAs (lncRNAs) that potentially participate in the initiation and progression of glioma have been widely reported. As a now-found lncRNA, HLA complex group 11 (HCG11) has not yet been studied in glioma. The present study aimed to determine the role of HCG11 in the tumorigenesis of glioma.

METHODS

A quantitative real-time polymerase chain reaction assay was performed to examine the expression pattern of HCG11 in 84 glioma tissues and cell lines. The overall survival rate of glioma patients with a high or low level of HCG11 or metastasis-associated 1 family member 3 (MTA3) was analyzed by Kaplan-Meier analysis. The effect of HCG11 on glioma cell growth was determined by in vitro and in vivo experiments. MicroRNAs (miRNAs) that potentially interact with HCG11 were searched and determined by bioinformatics analysis and a luciferase reporter assay. Similarly, the target of miRNA-4425 was identified. Finally, rescue assays were conducted to determine the bio-function of the competing endogenous RNA pathway.

RESULTS

HCG11 was downregulated in 84 pairs of glioma tissues and cell lines. Moreover, a low level of HCG11 indicted the lower overall survival rate of glioma patients. Regarding the mechanism, HCG11 was abundant in the cytoplasm of glioma cells and interacted with miR-4425 to release the expression of MTA3. miR-4425 and MTA3 participated in HCG11-mediated glioma growth.

CONCLUSIONS

LncRNA HCG11 suppresses the growth of glioma by cooperating with the miR-4425/MTA3 axis.

Landscape of tumor suppressor long noncoding RNAs in breast cancer

BACKGROUND

The landscape and biological functions of tumor suppressor long noncoding RNAs in breast cancer are still unknown.

METHODS

Data from whole transcriptome sequencing of 33 breast specimens in the Harbin Medical University Cancer Center cohort and The Cancer Genome Atlas was applied to identify and validate the landscape of tumor suppressor long noncoding RNAs, which was further validated by The Cancer Genome Atlas pancancer data including 33 cancer types and 12,839 patients. Next, the expression model, prognostic roles, potential biological functions and epigenetic regulation of tumor suppressor long noncoding RNAs were investigated and validated in the breast cancer and pancancer cohorts. Finally, EPB41L4A-AS2 was selected to validate our novel finding, and the tumor suppressive roles of EPB41L4A-AS2 in breast cancer were examined.

RESULTS

We identified and validated the landscape of tumor suppressor long noncoding RNAs in breast cancer. The expression of the identified long noncoding RNAs was downregulated in cancer tissue samples compared with normal tissue samples, and these long noncoding RNAs correlated with a favorable prognosis in breast cancer patients and the patients in the pancancer cohort. Multiple carcinogenesis-associated biological functions were predicted to be regulated negatively by these long noncoding RNAs. Moreover, these long noncoding RNAs were transcriptionally regulated by epigenetic modification, including DNA methylation and histone methylation modification. Finally, EPB41L4A-AS2 inhibited breast cancer cell proliferation, migration and invasion and induced cell apoptosis in vitro. Mechanistically, EPB41L4A-AS2, acting at least in part as a tumor suppressor, upregulated tumor suppressor gene expression. Moreover, ZNF217 recruited EZH2 to the EPB41L4A-AS2 locus and suppressed the expression of EPB41L4A-AS2 by epigenetically increasing H3K27me3 enrichment.

CONCLUSIONS

This work enlarges the functional landscape of known long noncoding RNAs in human cancer and provides novel insights into the suppressive roles of these long noncoding RNAs.

Long noncoding RNA FOXC2-AS1 facilitates the proliferation and progression of prostate cancer via targeting miR-1253/EZH2

The vital roles of long noncoding RNAs (lncRNAs) in the cancers have been evidenced. However, there are still numerous unsolved queries for the molecular mechanism. This study tries to investigate the role of lncRNA FOXC2-AS1 in the human prostate cancer tumorigenesis. Results stated that lncRNA FOXC2-AS1 was ectopically up-regulated in prostate cancer tissue and cells. The over-expression of FOXC2-AS1 indicates the poor prognosis of prostate cancer patients. Functionally, the gain- and loss-of-functional experiments revealed that FOXC2-AS1 promoted the proliferation and tumor growth of prostate cancer cells in vitro and in vivo. Mechanically, we found that miR-1253 targeted FOXC2-AS1 at the 3'‑untranslated regions (UTR), which in turn bind the EZH2 mRNA 3-UTR. Luciferase reporter assay and rescue experiment confirmed the FOXC2-AS1/miR-1253/EZH2 pathway. In conclusion, we confirmed that lncRNA FOXC2-AS1 accelerated the tumor progression of prostate cancer cells by regulating the proliferation and tumor growth through miR-1253/EZH2 axis.

RNAs as Candidate Diagnostic and Prognostic Markers of Prostate Cancer-From Cell Line Models to Liquid Biopsies

The treatment landscape of prostate cancer has evolved rapidly over the past five years. The explosion in treatment advances has been witnessed in parallel with significant progress in the field of molecular biomarkers. The advent of next-generation sequencing has enabled the molecular profiling of the genomic and transcriptomic architecture of prostate and other cancers. Coupled with this, is a renewed interest in the role of non-coding RNA (ncRNA) in prostate cancer biology. ncRNA consists of several different classes including small non-coding RNA (sncRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA). These families are under active investigation, given their essential roles in cancer initiation, development and progression. This review focuses on the evidence for the role of RNAs in prostate cancer, and their use as diagnostic and prognostic markers, and targets for treatment in this disease.

MicroRNA-194 regulates cell viability and apoptosis by targeting CDH2 in prostatic cancer

Introduction

Prostate cancer (PCa) is one of the most common malignancies in men. However, a lack of understanding of the mechanism underlying PCa metastasis has strongly limited the effectiveness of therapy for this disease. Thus, investigating the mechanism of PCa may help improve the prognosis of PCa patients. The goal of this study was to investigate the role of microRNA-194 (miR-194) in PCa.

Materials and methods

The expression of miR-194 and cadherin 2 (CDH2) at the transcriptional level was measured by quantitative real-time polymerase chain reaction (qRT-PCR). The MTT assay cell apoptosis assay and Western blotting were used to determine the role of miR-194 and CDH2 in the PC3 human PCa cell line. The dual luciferase reporter assay system was performed to clarify the relationship between miR-194 and CDH2. qRT-PCR results showed that miR-194 was downregulated and CDH2 was upregulated in PC3 cells.

Results

Transfection with miR-194 mimics decreased cell viability and increased the rate of apoptosis compared with the control group of PC3 cells. Bioinformatics and the luciferase reporter assay indicated that CDH2 was a target of miR-194, and Western blot analysis suggested that CDH2 was negatively regulated by miR-194. Further studies revealed that the downregulation of CDH2 suppressed cell viability and promoted the apoptosis of PC3 cells and that miR-194 directly targeted CDH2 in PC3 cells. Finally, the in vivo experiments showed that miR-194 mimics suppressed tumor growth and induced apoptosis in a greater proportion of cells by decreasing the expression of CDH2 compared with the control group.

Conclusion

The results of this study showed that miR-194 targeted CDH2 to regulate PCa cell survival in vitro and suppress tumor growth in vivo. These findings suggest that miR-194 may be a useful therapeutic target in PCa.

Pathological bases and clinical impact of long noncoding RNAs in prostate cancer: a new budding star

Long non-coding RNAs (lncRNAs) are functional RNAs longer than 200 nucleotides. Recent advances in the non-protein coding part of human genome analysis have discovered extensive transcription of large RNA transcripts that lack coding protein function, termed non-coding RNA (ncRNA). It is becoming evident that lncRNAs may be an important class of pervasive genes involved in carcinogenesis and metastasis. However, the biological and molecular mechanisms of lncRNAs in diverse diseases are not yet fully understood. Thus, it is anticipated that more efforts should be made to clarify the lncRNA world. Moreover, accumulating evidence has demonstrated that many lncRNAs are dysregulated in prostate cancer (PC) and closely related to tumorigenesis, metastasis, and prognosis or diagnosis. In this review, we will briefly outline the regulation and functional role of lncRNAs in PC. Finally, we discussed the potential of lncRNAs as prospective novel targets in PC treatment and biomarkers for PC diagnosis.

A Self-Training Subspace Clustering Algorithm under Low-Rank Representation for Cancer Classification on Gene Expression Data

Accurate identification of the cancer types is essential to cancer diagnoses and treatments. Since cancer tissue and normal tissue have different gene expression, gene expression data can be used as an efficient feature source for cancer classification. However, accurate cancer classification directly using original gene expression profiles remains challenging due to the intrinsic high-dimension feature and the small size of the data samples. We proposed a new self-training subspace clustering algorithm under low-rank representation, called SSC-LRR, for cancer classification on gene expression data. Low-rank representation (LRR) is first applied to extract discriminative features from the high-dimensional gene expression data; the self-training subspace clustering (SSC) method is then used to generate the cancer classification predictions. The SSC-LRR was tested on two separate benchmark datasets in control with four state-of-the-art classification methods. It generated cancer classification predictions with an overall accuracy 89.7 percent and a general correlation 0.920, which are 18.9 and 24.4 percent higher than that of the best control method respectively. In addition, several genes (RNF114, HLA-DRB5, USP9Y, and PTPN20) were identified by SSC-LRR as new cancer identifiers that deserve further clinical investigation. Overall, the study demonstrated a new sensitive avenue to recognize cancer classifications from large-scale gene expression data.

Insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) in cancer

The insulin-like growth factor-2 mRNA-binding protein 1 (IGF2BP1) plays essential roles in embryogenesis and carcinogenesis. IGF2BP1 serves as a post-transcriptional fine-tuner regulating the expression of some essential mRNA targets required for the control of tumor cell proliferation and growth, invasion, and chemo-resistance, associating with a poor overall survival and metastasis in various types of human cancers. Therefore, IGF2BP1 has been traditionally regarded as an oncogene and potential therapeutic target for cancers. Nevertheless, a few studies have also demonstrated its tumor-suppressive role. However, the details about the contradictory functions of IGF2BP1 are unclear. The growing numbers of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) have been identified as its direct regulators, during tumor cell proliferation, growth, and invasion in multiple cancers. Thus, the mechanisms of post-transcriptional modulation of gene expression mediated by IGF2BP1, miRNAs, and lncRNAs in determining the fate of the development of tissues and organs, as well as tumorigenesis, need to be elucidated. In this review, we summarized the tissue distribution, expression, and roles of IGF2BP1 in embryogenesis and tumorigenesis, and focused on modulation of the interconnectivity between IGF2BP1 and its targeted mRNAs or non-coding RNAs (ncRNAs). The potential use of inhibitors of IGF2BP1 and its related pathways in cancer therapy was also discussed.

Circular RNA Myosin Light Chain Kinase (MYLK) Promotes Prostate Cancer Progression through Modulating Mir-29a Expression

BACKGROUND In developed countries, prostate cancer (PCa) is a frequently diagnosed cancer with the second highest fatality rate. Circular RNAs (circRNAs) are a class of endogenous non-coding RNAs (ncRNAs) stably expressed in cells and involved in a series of carcinomas. However, few research studies have reported on the role of circRNAs in PCa. MATERIAL AND METHODS We used qRT-PCR to detect the expression of circMYLK (circRNA ID: hsa_circ_0141940) and miR-29a in PCa tissues and cell lines. MTT, colony formation, and TUNEL assays were performed to analysis the cell viability of PCa cells. Transwell and wound scratch assays were performed to investigate the cell invasion and migration of PCa cells. RESULTS In the present study, we confirmed that circMYLK expression level was significantly higher in PCa samples and PCa cells than in normal tissues and normal prostatic cells. The upregulated circRNA-MYLK promoted PCa cells proliferation, invasion, and migration; however, si-circRNA-MYLK significantly accelerated the PCa cell apoptosis. We also observed that the aforementioned function of circRNA-MYLK on PCa cells was affected through targeting miR-29a. CONCLUSIONS We confirmed circRNA-MYLK was an oncogene in PCa and revealed a novel mechanism underlying circRNA-MYLK in PC progression.

Increased expression of long non-coding RNA GLIDR in prostate cancer

Prostate cancer (PCa) was one of the most common cancers in males in China. Long non-coding RNAs (lncRNA), a class of non-coding RNAs with more than 200 nucleotides, played key roles in the progression of prostate cancer. GLIDR, a novel long intergenic ncRNA, was found to be upregulated in tumors compared to normal tissues by using publically databases. In the clinical validation cohort, our results showed GLIDR was significantly up-regulated in prostate cancer samples and cell lines. To explore the potential functions of the GLIDR, we constructed gene co-expression networks and applied GO analysis. Our analysis revealed that GLIDR was involved in the regulation of translational elongation, transcription, rRNA processing, RNA splicing, signal transduction, and cell adhesion. Furthermore, a GLIDR-mediated ceRNA network in prostate cancer was also identified. We believed that this study still provided some clues in exploring new therapeutic and prognostic targets for prostate cancer.

Carcinogenesis in prostate cancer: The role of long non-coding RNAs

LncRNAs appear to play a considerable role in tumourigenesis through regulating key processes in cancer cells such as proliferative signalling, replicative immortality, invasion and metastasis, evasion of growth suppressors, induction of angiogenesis and resistance to apoptosis. LncRNAs have been reported to play a role in prostate cancer, particularly in regulating the androgen receptor signalling pathway. In this review article, we summarise the role of 34 lncRNAs in prostate cancer with a particular focus on their role in the androgen receptor signalling pathway and the epithelial to mesenchymal transition pathway.

The prognostic value of abnormally expressed lncRNAs in prostatic carcinoma: A systematic review and meta-analysis

BACKGROUND

Several long noncoding RNAs (lncRNAs) are abnormally expressed in prostate cancer (PCa), suggesting that they could serve as novel prognostic markers. The current meta-analysis was undertaken to better define the prognostic value of various lncRNAs in PCa.

METHODS

The PubMed, Embase, Medline, and Cochrane Library databases were systematically searched up to February 19, 2017, to retrieve eligible articles. Outcomes analyzed were biochemical recurrence-free survival (BRFS), overall survival (OS), metastasis-free survival (MFS), and prostate cancer-specific survival (PCSS). Pooled hazard ratios (HRs) and 95% confidence intervals (95%CIs) were calculated using fixed-effects or random-effects models.

RESULTS

A total of 10 studies, evaluating 11 PCa-related lncRNAs, were included in the meta-analysis. Pooled results indicate that the abnormal expression of candidate lncRNAs in PCa samples predicted poor BRFS (HR: 1.67, 95%CI: 1.37-2.04, P < .05), without significant heterogeneity among studies (I = 44%, P = .06). Low PCAT14 expression was negatively associated with OS (HR: 0.66, 95%CI: 0.54-0.79, P < .05), MFS (HR: 0.59, 95%CI: 0.48-0.72, P < .05), and PCSS (HR: 0.50, 95%CI: 0.38-0.66, P < .05). Again, there was no significant heterogeneity among studies. The robustness of our results was confirmed by sensitivity and publication bias analyses.

CONCLUSION

We conclude that expression analysis of selected lncRNAs may be of prognostic value in PCa patients.