Long noncoding RNA LINC00152 promotes cell proliferation through competitively binding endogenous miR-125b with MCL-1 by regulating mitochondrial apoptosis pathways in ovarian cancer

LINC00152: Potential driver oncogene in pan-cancer

Long noncoding RNAs (lncRNA) are a class of non-coding RNAs greater than 200 bp in length with limited peptide-coding function. The transcription of LINC00152 is derived from chromosome 2p11.2. Many studies prove that LINC00152 influences the progression of various tumors via promoting the tumor cells malignant phenotype, chemoresistance, and immune escape. LINC00152 is regulated by multiple transcription factors and DNA hypomethylation. In addition, LINC00152 participates in the regulation of complex molecular signaling networks through epigenetic regulation, protein interactions, and competitive endogenous RNA (ceRNA). Here, we provide a systematic review of the upstream regulatory factors of LINC00152 expression level in different types of tumors. In addition, we revisit the main functions and mechanisms of LINC00152 as driver oncogene and biomarker in pan-cancer. This article is categorized under: RNA in Disease and Development > RNA in Disease RNA Methods > RNA Analyses in Cells RNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes.

Therapeutic advancements in targeting BCL-2 family proteins by epigenetic regulators, natural, and synthetic agents in cancer

Cancer is amongst the deadliest and most disruptive disorders, having a much higher death rate than other diseases worldwide. Human cancer rates continue to rise, thereby posing the most significant concerns for medical health professionals. In the last two decades, researchers have gone past several milestones in tackling cancer while gaining insight into the role of apoptosis in cancer or targeting various biomarker tools for prognosis and diagnosis. Apoptosis which is still a topic full of complexities, can be controlled considerably by B-cell lymphoma 2 (BCL-2) and its family members. Therefore, targeting proteins of this family to prevent tumorigenesis, is essential to focus on the pharmacological features of the anti-apoptotic and pro-apoptotic members, which will help to develop and manage this disorder. This review deals with the advancements of various epigenetic regulators to target BCL-2 family proteins, including the mechanism of several microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). Similarly, a rise in natural and synthetic molecules' research over the last two decades has allowed us to acquire insights into understanding and managing the transcriptional alterations that have led to apoptosis and treating various neoplastic diseases. Furthermore, several inhibitors targeting anti-apoptotic proteins and inducers or activators targeting pro-apoptotic proteins in preclinical and clinical stages have been summarized. Overall, agonistic and antagonistic mechanisms of BCL-2 family proteins conciliated by epigenetic regulators, natural and synthetic agents have proven to be an excellent choice in developing cancer therapeutics.

A review on the role of LINC00152 in different disorders

LINC00152 is an important lncRNA in human disorders. It is mainly regarded as a tumor-promoting lncRNA. Mechanistically, LINC00152 serves as a molecular sponge for miR-143a-3p, miR-125a-5p, miR-139, miR-215, miR-193a/b-3p, miR-16-5p, miR-206, miR-195, miR-138, miR-185-5p, miR-103, miR-612, miR-150, miR-107, miR-205-5p and miR-153-3p. In addition, it can regulate activity of mTOR, EGFR/PI3K/AKT, ERK/MAPK, Wnt/β-Catenin, EGFR, NF-κB, HIF-1 and PTEN. In this review, we provide a concise but comprehensive explanation about the role of LINC00152 in tumor development and progression as well as its role in the pathology of non-malignant conditions with the aim of facilitating the clinical implementation of this lncRNA as a diagnostic or prognostic tumor marker and therapeutic target.

Understanding MCL1: from cellular function and regulation to pharmacological inhibition

Myeloid cell leukemia-1 (MCL1), an antiapoptotic member of the BCL2 family characterized by a short half-life, functions as a rapid sensor that regulates cell death and other relevant processes that include cell cycle progression and mitochondrial homeostasis. In cancer, MCL1 overexpression contributes to cell survival and resistance to diverse chemotherapeutic agents; for this reason, several MCL1 inhibitors are currently under preclinical and clinical development for cancer treatment. However, the nonapoptotic functions of MCL1 may influence their therapeutic potential. Overall, the complexity of MCL1 regulation and function represent challenges to the clinical application of MCL1 inhibitors. We now summarize the current knowledge regarding MCL1 structure, regulation, and function that could impact the clinical success of MCL1 inhibitors.

Long non-coding RNA LINC00152 in cancer: Roles, mechanisms, and chemotherapy and radiotherapy resistance

Long non-coding RNA LINC00152 (cytoskeleton regulator, or LINC00152) is an 828-bp lncRNA located on chromosome 2p11.2. LINC00152 was originally discovered during research on hepatocarcinogenesis and has since been regarded as a crucial oncogene that regulates gene expression in many cancer types. LINC00152 is aberrantly expressed in various cancers, including gastric, breast, ovarian, colorectal, hepatocellular, and lung cancer, and glioma. Several studies have indicated that LINC00152 is correlated with cell proliferation, apoptosis, migration, invasion, cell cycle, epithelial-mesenchymal transition (EMT), chemotherapy and radiotherapy resistance, and tumor growth and metastasis. High LINC00152 expression in most tumors is significantly associated with poor patient prognosis. Mechanistic analysis has demonstrated that LINC00152 can serve as a competing endogenous RNA (ceRNA) by sponging miRNA, regulating the abundance of the protein encoded by a particular gene, or modulating gene expression at the epigenetic level. LINC00152 can serve as a diagnostic or prognostic biomarker, as well as a therapeutic target for most cancer types. In the present review, we discuss the roles and mechanisms of LINC00152 in human cancer, focusing on its functions in chemotherapy and radiotherapy resistance.

ZNF750 facilitates carcinogenesis via promoting the expression of long non-coding RNA CYTOR and influences pharmacotherapy response in colon adenocarcinoma

The epidermal cell differentiation regulator zinc finger protein 750 (ZNF750) is a transcription factor containing the Cys2His2 (C2H2) domain, the zinc finger structure of which is located at the N-terminal 25‍‍-‍46 amino acids of ZNF750. It can promote the expression of differentiation-related factors while inhibiting the expression of progenitor cell-related genes. ZNF750 is directly regulated by p63 (encoded by the TP63 gene, belonging to the TP53 superfamily). The Krüppel-like factor 4 (KLF4), repressor element-1 (RE-1)‍-silencing transcription factor (REST) corepressor 1 (RCOR1), lysine demethylase 1A (KDM1A), and C-terminal-binding protein 1/2 (CTBP1/2) chromatin regulators cooperate with ZNF750 to repress epidermal progenitor genes and activate the expression of epidermal terminal differentiation genes (Sen et al., 2012; Boxer et al., 2014). Besides, ZNF750 and the regulatory network composed of bone morphogenetic protein (BMP) signaling pathway, long non-coding RNAs (lncRNAs) (anti-differentiation non-coding RNA (ANCR) and tissue differentiation-inducing non-protein coding RNA (TINCR)), musculoaponeurotic fibrosarcoma oncogene (MAF)/MAF family B (MAFB), grainy head-like 3 (GRHL3), and positive regulatory domain zinc finger protein 1 (PRDM1) jointly promote epidermal cell differentiation (Sen et al., 2012).

LINC00152 Drives a Competing Endogenous RNA Network in Human Hepatocellular Carcinoma

Genomic and epigenomic studies revealed dysregulation of long non-coding RNAs in many cancer entities, including liver cancer. We identified an epigenetic mechanism leading to upregulation of the long intergenic non-coding RNA 152 (LINC00152) expression in human hepatocellular carcinoma (HCC). Here, we aimed to characterize a potential competing endogenous RNA (ceRNA) network, in which LINC00152 exerts oncogenic functions by sponging miRNAs, thereby affecting their target gene expression. Database and gene expression data of human HCC were integrated to develop a potential LINC00152-driven ceRNA in silico. RNA immunoprecipitation and luciferase assay were used to identify miRNA binding to LINC00152 in human HCC cells. Functionally active players in the ceRNA network were analyzed using gene editing, siRNA or miRNA mimic transfection, and expression vectors in vitro. RNA expression in human HCC in vivo was validated by RNA in situ hybridization. Let-7c-5p, miR-23a-3p, miR-125a-5p, miR-125b-5p, miR-143a-3p, miR-193-3p, and miR-195-5p were detected as new components of the potential LINC00152 ceRNA network in human HCC. LINC00152 was confirmed to sponge miR143a-3p in human HCC cell lines, thereby limiting its binding to their respective target genes, like KLC2. KLC2 was identified as a central mediator promoting pro-tumorigenic effects of LINC00152 overexpression in HCC cells. Furthermore, co-expression of LINC00152 and KLC2 was observed in human HCC cohorts and high KLC2 expression was associated with shorter patient survival. Functional assays demonstrated that KLC2 promoted cell proliferation, clonogenicity and migration in vitro. The LINC00152-miR-143a-3p-KLC2 axis may represent a therapeutic target in human HCC.

Long non-coding RNA OIP5-AS1 suppresses microRNA-92a to augment proliferation and metastasis of ovarian cancer cells through upregulating ITGA6

OBJECTIVE

Recently, long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) have been identified as essential biomarkers during development of malignancies. This study was performed to study the roles of lncRNA opa-interacting protein 5 antisense transcript 1 (OIP5-AS1) and miR-92a in ovarian cancer (OC).

METHODS

OIP5-AS1, miR-92a and integrin alpha 6 (ITGA6) expression in OC tissues and cells was assessed. The screened OC cells were respectively with OIP5-AS1-, miR-92a- and ITGA6-related vectors or oligonucleotides . The viability, migration, invasion and apoptosis of the cells were determined and the levels of epithelial-mesenchymal transition (EMT)-related proteins were also measured. The interactions between OIP5-AS1 and miR-92a, and between miR-92a and ITGA6 were confirmed.

RESULTS

OIP5-AS1 and ITGA6 were upregulated while miR-92a was downregulated in OC. Inhibited OIP5-AS1 or downregulated ITGA6 or elevated miR-92a repressed EMT, viability, migration and invasion, and promoted apoptosis of OC cells. OIP5-AS1 as a competing endogenous RNA interacted with miR-92a to regulate ITGA6. These effects that induced by silenced OIP5-AS1 could be reversed by miR-92a inhibition while those that induced by up-regulated miR-92a were reduced by restored ITGA6.

CONCLUSION

OIP5-AS1 silencing promoted miR-92a to repress proliferation and metastasis of OC cells through inhibiting ITGA6.

Chlamydia trachomatis induces lncRNA MIAT upregulation to regulate mitochondria-mediated host cell apoptosis and chlamydial development

Chlamydia trachomatis persistent infection is the leading cause of male prostatitis and female genital tract diseases. Inhibition of host cell apoptosis is the key to maintaining Chlamydia survival in vivo, and long noncoding RNAs (lncRNAs) play important roles in its developmental cycle and pathogenesis. However, it is not clear how lncRNAs regulate persistent Chlamydia infection. Here, using a microarray method, we identified 1718 lncRNAs and 1741 mRNAs differentially expressed in IFN-γ-induced persistent C. trachomatis infection. Subsequently, 10 upregulated and 5 downregulated differentially expressed lncRNAs were verified by qRT-PCR to confirm the reliability of the chip data. The GO and KEGG analyses revealed that differentially regulated transcripts were predominantly involved in various signalling pathways related to host immunity and apoptosis response. Targeted silencing of three lncRNAs (MIAT, ZEB1-AS1 and IRF1) resulted in increased apoptosis rates. Furthermore, interference with lncRNA MIAT caused not only an obvious downregulation of the Bcl-2/Bax ratio but also a marked release of cytochrome c, resulting in a significantly elevated level of caspase-3 activation. Meanwhile, MIAT was involved in the regulation of chlamydial development during the persistent infection. Collectively, these observations shed light on the enormous complex lncRNA regulatory networks involved in mitochondria-mediated host cell apoptosis and the growth and development of C. trachomatis.

LncRNA MNX1-AS1 promotes ovarian cancer process via targeting the miR-744-5p/SOX12 axis

Purpose

Ovarian cancer (OC) is the most common malignancy in women with high mortality. Increasing studies have revealed that long non-coding RNA (lncRNA) MNX1-AS1 has a promoting effect on various cancers. However, the mechanisms of MNX1-AS1 in OC are still unclear. Therefore, this study focused on exploring the mechanisms of MNX1-AS1 in OC.

Materials and methods

The expression of SOX12 at the protein level was detected by western blot. Cell proliferation was detected by CCK8 assay and colony formation assay. Cell cycle and cell apoptosis were detected by flow cytometry. Wound-healing assay, transwell assay and western blot were used to detect the ability of cell migration and invasion. The target binding was confirmed through the luciferase reporter assay.

Results

The expression of MNX1-AS1 was increased in OC tumor tissues and cells. Elevated MNX1-AS1 expression is associated with advanced stage and lower overall survival rate. Knockdown of MNX1-AS1 inhibited cell proliferation, migration and invasion, blocked cell cycle, and promoted cell apoptosis in SKOV-3 and OVCAR-3 cells. MNX1-AS1 was competitively binding with miR-744-5p, and its downstream target gene was SOX12. miR-544-5p expression was decreased, while SOX12 expression was increased in OC tumor tissues and cells. Overexpression of miR-744-5p inhibited cell proliferation, migration, invasion and promoted cell apoptosis in SKOV-3 and OVCAR-3 cells.

Conclusion

MNX1-AS1 promoted the development of OC through miR-744-5p/SOX12 axis. This study revealed a novel mechanism of MNX1-AS1 in OC, which may provide a new treatment or scanning target for OC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13048-021-00910-0.

Long Non-coding RNAs: Potential Players in Cardiotoxicity Induced by Chemotherapy Drugs

One of the most important side effects of chemotherapy is cardiovascular complications, such as cardiotoxicity. Many factors are involved in the pathogenesis of cardiotoxicity; one of the most important of which is long non-coding RNAs (lncRNAs). lncRNA has 200-1000 nucleotides. It is involved in important processes such as cell proliferation, regeneration and apoptosis; today it is used as a prognostic and diagnostic factor. A, various drugs by acting on lncRNAs can affect cells. Therefore, by accurately identifying IncRNAs function, we can play an effective role in preventing the development of cardiotoxicity-induced chemotherapy drugs, and use them as a therapeutic strategy to improve clinical symptoms and increase patient survival.

Research Progress in Prognostic Factors and Biomarkers of Ovarian Cancer

Ovarian cancer is a serious threat to women's health; its early diagnosis rate is low and prone to metastasis and recurrence. The current conventional treatment for ovarian cancer is a combination of platinum and paclitaxel chemotherapy based on surgery. The recurrence and progression of ovarian cancer with poor prognosis is a major challenge in treatment. With rapid advances in technology, understanding of the molecular pathways involved in ovarian cancer recurrence and progression has increased, biomarker-guided treatment options can greatly improve the prognosis of patients. This review systematically discusses and summarizes existing and new information on prognostic factors and biomarkers of ovarian cancer, which is expected to improve the clinical management of patients and lead to effective personalized treatment.

Mechanisms of Apoptosis-Related Long Non-coding RNAs in Ovarian Cancer

Ovarian cancer is a health-threatening malignancy of ovary in female reproductive systems and one of the most common gynecological malignancies worldwide. Due to rare early symptoms, ovarian cancers are often diagnosed at advanced stages and exhibit poor prognosis. Thus, efforts have been paid to develop alternative diagnostic and therapeutic strategies for the disease. Recent studies have presented that some long non-coding RNAs (lncRNAs) play roles in apoptosis of ovarian cancer cells through various mechanisms involved in the regulation of transcription factors, histone modification complexes, miRNAs, and protein stability. Because evasion of apoptosis in cancer cells facilitates to promote tumor progression and therapy resistance, apoptosis regulatory mechanisms of lncRNAs may be promising new targets in ovarian cancer. In this review, we introduce the recent findings in regard to the molecular mechanisms of apoptosis-related lncRNAs in ovarian cancer cells.

The lncRNA SLCO4A1-AS1/miR-876-3p/RBBP6 axis regulates cell proliferation and apoptosis in acute lymphocytic leukemia via the JNK signaling pathway

INTRODUCTION

Acute lymphocytic leukemia (ALL) is a hematologic malignancy caused by the clonal proliferation of immature lymphocytes. Long noncoding RNAs (lncRNAs) have been reported as critical regulators in several cancers, including ALL. LncRNA SLCO4A1 antisense RNA 1 (SLCO4A1-AS1) has been revealed to be implicated in tumorigenesis of several cancers. Our study focused on the role of SLCO4A1-AS1 in ALL.

METHODS

RT-qPCR, Western blot analysis, CCK-8, EdU, and Flow cytometry analysis were used to explore the biological function of SLCO4A1-AS1 in ALL cellular processes. Luciferase reporter and RNA pull-down assays were applied to explore the mechanism of SLCO4A1-AS1 in ALL cells.

RESULTS

SLCO4A1-AS1 was upregulated in ALL tissues and cell lines. We found that suppression of SLCO4A1-AS1 suppressed ALL cell proliferation and facilitated cell apoptosis. Our result confirmed that SLCO4A1-AS1 acted as a ceRNA by sponging microRNA 876-3p (miR-876-3p) to upregulate retinoblastoma binding protein 6 (RBBP6) expression in ALL cells. Moreover, SLCO4A1-AS1 activated the JNK signaling pathway by upregulating RBBP6. Rescue assays revealed that the activation of the JNK signaling or overexpression of RBBP6 revered the suppressive effect of SLCO4A1-AS1 knockdown on growth of ALL cells.

CONCLUSION

SLCO4A1-AS1 promoted cell growth of ALL by the miR-876-3p/RBBP6 axis to activate the JNK signaling pathway.

ELK1 activated-long noncoding RNA LBX2-AS1 aggravates the progression of ovarian cancer through targeting miR-4784/KDM5C axis

As one of the most common cancers in female, ovarian cancer (OC) has become a serious public burden now. Mounting researches have indicated long noncoding RNAs (lncRNAs) can affect many biological processes including cancer development. LncRNA LBX2-AS1 was identified to be an oncogene in some cancers, but the role of LBX2-AS1 in OC remains to be elucidated. Bioinformatics analysis and experiments including ChIP, RT-qPCR, RIP, luciferase reporter, western blot and CCK-8 were performed to explore the role of LBX2-AS1 in OC. LBX2-AS1 expression was markedly increased in OC tissues and cell lines. Functionally, LBX2-AS1 silencing inhibited cell proliferation, migration and stemness but facilitated cell apoptosis in OC. Moreover, depletion of LBX2-AS1 suppressed tumor growth of OC in vivo. Mechanically, LBX2-AS1 was activated by transcriptional factor ELK1. ELK1 enhanced the expression of LBX2-AS1 in OC cells. In addition, miR-4784 was confirmed to be sponged by LBX2-AS1. There was a negative expression correlation between LBX2-AS1 and miR-4784 in OC tissues. Subsequently, KDM5C was identified to be a direct target of miR-4784 in OC cells. KDM5C was negatively regulated by miR-4784 and positively regulated by LBX2-AS1 in terms of expression level. Upregulation of KDM5C reversed the inhibitory effect of LBX2-AS1 depletion on the progression of OC. This study proved that ELK1 activated-LBX2-AS1 aggravated the progression of OC by targeting the miR-4784/KDM5C axis, suggesting that LBX2-AS2 may be a promising diagnostic biomarker of OC.

LINC00494 Promotes Ovarian Cancer Development and Progression by Modulating NFκB1 and FBXO32

BACKGROUND

Ovarian cancer represents one of the most frequent gynecological cancers and is significant cause of death for women around the world. Long non-coding RNAs (lncRNAs) are recognized as critical governors of gene expression during carcinogenesis, but their effects on the occurrence and development of ovarian cancer require further investigation. In this report, we characterized LINC00494 as a novel oncogenic lncRNA in ovarian cancer.

METHODS

Bioinformatics analysis predicted potential interactions among LINC00494, NFκB1, and FBXO32 in ovarian cancer, which were tested by dual-luciferase reporter assay, RNA pull-down, RIP, and ChIP assay. Cancer cells were transfected with relevant treated plasmids, followed by scratch and Transwell assays. The treated cells were injected into nude mice to establish a xenograft model for testing effects of LINC00494 and its target gene in vivo.

RESULTS

LINC00494 and NFκB1 were highly expressed whereas FBXO32 had low expression in ovarian cancer cells and tissues. LINC00494 was found to bind NFκB1 and increase its activity, while NFκB1 was enriched at the FBXO32 promoter region, where it acted to reduce FBXO32 transcription. Overexpression of LINC00494 elevated NFκB1 expression and enhanced cell migration, invasion and tumorigenesis, but additional overexpression of FBXO32 interfered with the tumorgenicity of ovarian cancer cells in vitro and in vivo.

CONCLUSION

Our work demonstrated that LINC00494 promoted ovarian cancer progression by modulating FBXO32 via binding with the transcription factor NFκB1. These results provided new insight into the mechanism of ovarian cancer pathogenesis and suggested new therapeutic targets.

Role of LINC00152 in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) accounts for about 85% of all lung cancer cases. The pathogenesis of NSCLC involves complex gene networks that include different types of non-coding RNAs, such as long non-coding RNAs (lncRNAs). The role of lncRNAs in NSCLC is gaining an increasing interest as their function is being explored in various human cancers. Recently, a new oncogenic lncRNA, LINC00152 (cytoskeleton regulator RNA (CYTOR)), has been identified in different tumor types. In NSCLC, the high expression of LINC00152 in tumor tissue and peripheral blood samples has been shown to be associated with worse prognoses of NSCLC patients. Overexpression of LINC00152 has been confirmed to promote the proliferation, invasion, and migration of NSCLC cells in vitro, as well as increase tumor growth in vivo. This review discusses the role of LINC00152 in NSCLC.

Ovarian Cancer Stem Cells: Characterization and Role in Tumorigenesis

Ovarian cancer is a heterogenous disease with variable clinicopathological and molecular mechanisms being responsible for tumorigenesis. Despite substantial technological improvement, lack of early diagnosis contributes to its highest mortality. Ovarian cancer is considered to be the most lethal female gynaecological cancer across the world. Conventional treatment modules with platinum- and Taxane-based chemotherapy can cause an initial satisfactory improvement in ovarian cancer patients. However, approximately 75-80% patients of advanced stage ovarian cancer, experience relapse and nearly 40% have overall poor survival rate. It has been observed that a subpopulation of cells referred as cancer stem cells (CSCs), having self renewal property, escape the conventional chemotherapy because of their quiescent nature. Later, these CSCs following its interaction with microenvironment and release of various inflammatory cytokines, chemokines and matrix metalloproteinases, induce invasion and propagation to distant organs of the body mainly peritoneal cavity. These CSCs can be enriched by their specific surface markers such as CD44, CD117, CD133 and intracellular enzyme such as aldehyde dehydrogenase. This tumorigenicity is further aggravated by the epithelial to mesenchymal transition of CSCs and neovascularisation via epigenetic reprogramming and over-expression of various signalling cascades such as Wnt/β-catenin, NOTCH, Hedgehog, etc. to name a few. Hence, a comprehensive understanding of various cellular events involving interaction between cancer cells and cancer stem cells as well as its surrounding micro environmental components would be of unmet need to achieve the ultimate goal of better management of ovarian cancer patients. This chapter deals with the impact of ovarian cancer stem cells in tumorigenesis which would help in the implementation of basic research into the clinical field in the form of translational research in order to reduce the morbidity and mortality in ovarian cancer patients through amelioration of diagnosis and impoverishment of therapeutic resistance.

Essential functions of miR-125b in cancer

MicroRNAs (miRNAs) are small and highly conserved non-coding RNAs that silence target mRNAs, and compelling evidence suggests that they play an essential role in the pathogenesis of human diseases, especially cancer. miR-125b, which is the mammalian orthologue of the first discovered miRNA lin-4 in Caenorhabditis elegans, is one of the most important miRNAs that regulate various physiological and pathological processes. The role of miR-125b in many types of cancer has been well established, and so here we review the current knowledge of how miR-125b is deregulated in different types of cancer; its oncogenic and/or tumour-suppressive roles in tumourigenesis and cancer progression; and its regulation with regard to treatment response, all of which are underlined in multiple studies. The emerging information that elucidates the essential functions of miR-125b might help support its potentiality as a diagnostic and prognostic biomarker as well as an effective therapeutic tool against cancer.

Genetic Polymorphisms of PRNCR1 and Lung Cancer Risk in Chinese Northeast Population: A Case-Control Study and Meta-Analysis

Long noncoding RNAs (lncRNAs) play vital roles in development and progression of various cancers. To investigate the relationship between three tag single-nucleotide polymorphisms (SNPs) (rs13252298, rs1016343, and rs1456315) in lncRNA prostate cancer-associated noncoding RNA 1 (PRNCR1) and lung cancer (LC) risk, we conducted this study. First, we performed a case-control study, including 576 LC patients and 612 cancer-free controls. Second, a meta-analysis was used to evaluate the association of selected SNPs with risk of overall cancer. We found that rs13252298 and rs1456315 were strongly correlated with risk of LC, nonsmall cell lung cancer (NSCLC), and lung adenocarcinoma. For rs13252298, individuals carrying GG genotype had increased risks of LC compared with those carrying AA genotype (adjusted odds ratio [OR] = 1.565, 95% CI = 1.091-2.245, p = 0.015). A significant result was also found in recessive model with adjusted OR of 1.719. Individuals with GG genotype of rs1456315 were at increased risks of LC compared with those carrying AA genotype. Similar results were found in NSCLC patients. Meta-analysis showed that rs1016343 and rs13252298 were associated with overall cancer. But for rs1016343, no significant association was observed in Asians. In conclusion, rs13252298 and rs1456315 in PRNCR1 may be genetic susceptibility factors for LC in Chinese population. These results need to be confirmed by further studies.

LncRNAs in Ovarian Cancer Progression, Metastasis, and Main Pathways: ceRNA and Alternative Mechanisms

Ovarian cancer (OvCa) develops asymptomatically until it reaches the advanced stages with metastasis, chemoresistance, and poor prognosis. Our review focuses on the analysis of regulatory long non-coding RNAs (lncRNAs) competing with protein-coding mRNAs for binding to miRNAs according to the model of competitive endogenous RNA (ceRNA) in OvCa. Analysis of publications showed that most lncRNAs acting as ceRNAs participate in OvCa progression: migration, invasion, epithelial-mesenchymal transition (EMT), and metastasis. More than 30 lncRNAs turned out to be predictors of survival and/or response to therapy in patients with OvCa. For a number of oncogenic (CCAT1, HOTAIR, NEAT1, and TUG1 among others) and some suppressive lncRNAs, several lncRNA/miRNA/mRNA axes were identified, which revealed various functions for each of them. Our review also considers examples of alternative mechanisms of actions for lncRNAs besides being ceRNAs, including binding directly to mRNA or protein, and some of them (DANCR, GAS5, MALAT1, and UCA1 among others) act by both mechanisms depending on the target protein. A systematic analysis based on the data from literature and Panther or KEGG (Kyoto Encyclopedia of Genes and Genomes) databases showed that a significant part of lncRNAs affects the key pathways involved in OvCa metastasis, EMT, and chemoresistance.

Network-Based Coexpression Analysis Identifies Functional and Prognostic Long Noncoding RNAs in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a primary liver cancer associated with a growing incidence and extremely high mortality. However, the pathogenic mechanism is still not fully understood. In the present study, we identified 1,631 upregulated and 1,515 downregulated genes and found that cell cycle and metabolism-related pathways or biological processes highly dysregulated in HCC. To assess the biological importance of these DEGs, we carried out weighted gene coexpression network analysis (WGCNA) to identify the functional modules potentially involved in HCC pathogenesis or progression. The five modules were detected with Dynamic Tree Cut algorithm, and GO enrichment analysis revealed that these modules exhibited different biological processes or signaling pathways, such as metabolism-related pathways, cell proliferation-related pathways, and molecules in tumor microenvironment. Moreover, we also observed two immune cells, namely, cytotoxic cells and macrophage enriched in modules grey and brown, respectively, while T helper cell-2 (Th2) was enriched in module turquoise. Among the WGCNA network, four hub long noncoding RNAs (lncRNAs) were identified to be associated with HCC prognostic outcomes, suggesting that coexpression network analysis could uncover lncRNAs with functional importance, which may be associated with prognostic outcomes of HCC patients. In summary, this study demonstrated that network-based analysis could identify some functional modules and some hub-lncRNAs, which may be critical for HCC pathogenesis or progression.

LncRNA LINC00857 regulates the progression and glycolysis in ovarian cancer by modulating the Hippo signaling pathway

Ovarian cancer is one of the most common gynecological cancers with high morbidity and mortality, which seriously endangers women's health and quality of life. Long noncoding RNAs (lncRNAs) can regulate the progression of cancers, including ovarian cancer. LINC00857 (long intergenic non‐protein coding RNA 857) has been discovered to be a crucial factor in the regulation of cancer development. Nevertheless, the specific functions and mechanisms of LINC00857 in ovarian cancer remain unclear. The Hippo signaling pathway can involve in cancer progression. In our research, we aimed to investigate the correlation of LINC00857 and Hippo pathway. Quantitative real‐time polymerase chain reaction assay was utilized to test the expression of LINC00857 in ovarian cancer tissues and cells. Functional experiments revealed that LINC00857 silencing led to the inhibition on cell proliferation, migration, invasion, and glycolysis but accelerated cell apoptosis in ovarian cancer. Mechanism experiments, including RNA immunoprecipitation, RNA pull‐down, and luciferase reporter experiments demonstrated that LINC00857 could regulate YAP1 (Yes1 associated transcriptional regulator) by competitively binding to miR‐486‐5p in ovarian cancer. In a word, this study unveiled that LINC00857 regulates YAP1 by competitively binding to miR‐486‐5p and accelerates ovarian cancer progression.

Regulation of human Mcl-1 by a divergently-expressed antisense transcript

Mcl-1 is a member of the Bcl-2 anti-apoptotic protein family with important roles in the development, lifespan and metabolism of lymphocytes, as well as oncogenesis. Mcl-1 displays the shortest half-life of all Bcl-2 family members, with miRNA interference and proteasomal degradation being major pathways for Mcl-1 downregulation. In this study, we have identified a previously undescribed control mechanism active at the RNA level. A divergently transcribed lncRNA LOC107985203 (named here mcl1-AS1) negatively modulated Mcl-1 expression resulting in downregulation of Mcl-1 at both mRNA and protein level in a time-dependent manner. Using reporter assays, we confirmed that the mcl1-AS1 lncRNA promoter was located within Mcl-1 coding region. We next placed mcl1-AS1 under tetracycline-inducible control and demonstrated decreased viability in HEK293 cells upon doxycycline induction. Inhibition of mcl1-AS1 with shRNA reversed drug sensitivity. Bioinformatics surveys predicted direct mcl1-AS1 lncRNA binding to Mcl-1 transcripts, suggesting its mechanism in Mcl-1 expression is at the transcriptional level, consistent with a common role for anti-sense transcripts. The identification of a bi-directional promoter and lncRNA controlling Mcl-1 expression will have implications for controlling Mcl-1 activity in cancer cells, or for the purpose of enhancing the lifespan and quality of anti-cancer T lymphocytes.

Zebrafish xenograft model of human lung cancer for studying the function of LINC00152 in cell proliferation and invasion

Background

Numerous studies have shown that long noncoding RNAs play important roles in human cancer progression. Although zebrafish xenografts have recently become a novel in vivo model for human cancer research, whether such models can be used to study the function of long noncoding RNAs remains unknown.

Methods

In vitro studies validated the roles of LINC00152 in the proliferation and invasion of lung cancer cells. In vivo studies of zebrafish xenografts also confirmed these roles of LINC00152. In vivo confocal imaging was used to more accurately evaluate the function of LINC00152 in cell proliferation and migration. Pharmacological experiments were further performed to study the potential ability of LINC00152 downregulation combined with an EGFR inhibitor to treat tumors in cultured cells and the zebrafish xenograft model.

Results

Silencing of LINC00152 suppressed cell proliferation and invasion in SPCA1 and A549 lung cancer cell lines in vitro. In the zebrafish xenograft model, knockdown of LINC00152 reduced the proliferation and migration of lung cancer cells, as indicated by the two imaging methods at different magnifications. Moreover, the knockdown of LINC00152 enhanced the inhibition effect of afatinib for lung cancer progression in cultured cells and the zebrafish xenograft model.

Conclusion

Our study reveals the oncogenic roles and potential for LINC00152 to be a target for tumor treatment in lung cancer using zebrafish xenograft models, and the findings suggest that this model could be used for functional and application studies of human long noncoding RNAs in tumor biology.

LncRNA LINC00152 Promotes Laryngeal Cancer Progression by Sponging MiR-613

Background

Long noncoding RNA (lncRNA) LINC00152 (CYTOR) has been reported to be upregulated and to serve as a diagnostic biomarker in multiple types of cancers, including laryngeal squamous cell cancer (LSCC). However, the functional role and molecular mechanisms of LINC00152 in LSCC progression need to be further investigated.

Methods

LINC00152 levels in LSCC and adjacent normal tissues were measured by quantitative real-time polymerase chain reaction (qRT-PCR). Gene knockdown of LINC00152 was achieved in LSCC cells by use of small interfering RNA (siRNA). Cell proliferation, apoptosis, migration and invasion were examined by a series of methods. The micoRNA (miRNA) interaction with LINC00152 was screened by starBase v2.0 and confirmed by luciferase reporter activity.

Results

LINC00152 levels in LSCC tissues were significantly higher than those in adjacent normal tissue, and patients with lymph node metastasis or an advanced clinical stage displayed higher LINC00152 expression. Moreover, siRNA-mediated LINC00152 knockdown significantly inhibited the proliferation, migration and invasion of LSCC cells and induced apoptosis in those cells. Mechanistically, LINC00152 functioned as a competing endogenous RNA (ceRNA) sponging miR-613. The inhibitory effect of LINC00152 knockdown on malignant behavior was abrogated by inhibiting miR-613.

Conclusion

LINC00152 exerts an oncogenic effect on the tumorigenesis of LSCC by sponging miR-613 and may serve as a potential target for treating LSCC.

Integrated analysis of gene expression and DNA methylation profiles in ovarian cancer

BACKGROUND

Ovarian cancer is an epithelial malignancy that intrigues people for its poor outcome and lack of efficient treatment, while methylation is an important mechanism that have been recognized in many malignancies. In this study, we attempt to assess abnormally methylated gene markers and pathways in ovarian cancer by integrating three microarray datasets.

METHODS

Three datasets including expression (GSE26712 and GSE66957) and methylation (GSE81224) datasets were accessed. GEO2R platform was used to detect abnormally methylated-differentially expressed genes. Protein-protein interaction (PPI) networks were built and analysed for hypermethylated and hypermethylated differentially expressed genes using Cytoscape software and Mcode app. GEPIA and cBioPortal platforms were used to validate the expression of the hub genes and the correlation between their mRNA expressions and methylation levels. Kaplan Meier-plotter platform were used to assess the prognostic significance of the hub genes.

RESULTS

Six hundred eighty-one hypomethylated-upregulated genes were detected and involved in Rap1 signaling pathway, biosynthesis of amino acids, endocrine resistance, apoptosis, pathways in cancer. The hub genes were TNF, UBC, SRC, ESR1, CDK1, PECAM1, CXCR4, MUC1, IKBKG. Additionally, 337 hypermethylated-downregulated genes were detected and involved in pathways in cancer, focal adhesion, sphingolipid signaling pathway, EGFR tyrosine kinase inhibitor resistance, cellular senescence. The hub genes were BDNF, CDC42, CD44, PPP2R5C, PTEN, UBB, BMP2, FOXO1, KLHL2. TNF, ESR1, MUC1, CD44, PPP2R5C, PTEN, UBB and FOXO1 showed significant negative correlation between their mRNA expressions and methylation levels. TNF, ESR1 and FOXO1 showed prognostic significance.

CONCLUSIONS

Two novel gene networks were found for ovarian cancer. TNF, ESR1, MUC1 and FOXO1 are our candidate genes that might take part in ovarian cancer progression in an epigenetic approach, TNF, ESR1 and FOXO1 may serve as potential markers for ovarian cancer prognosis evaluation.

LINC00963 Promotes Ovarian Cancer Proliferation, Migration and EMT via the miR-378g /CHI3L1 Axis

BACKGROUND

Long non-coding RNA (lncRNAs) are involved in the development and progression of numerous tumors. Nevertheless, their role in ovarian cancer (OC) needs further study.

METHODS

A pivotal lncRNA that modulated OC to metastasize was determined in this research, and its potential mechanism was inquired by qRT-PCR, CCK-8, EdU, Transwell assay, wound healing assay and Western blot assay.

RESULTS

In our study, the GSE119054 microarray was analyzed, and LINC00963 showed a significant higher level in ovarian cancer tissues compared with controls. So LINC00963 was selected as research object. It was discovered that LINC00963 displayed a close relationship with unfavorable prognosis, and it was prominently raised in OC tissues of patients with lymph node metastasis. What's more, LINC00963 downregulation in OC cells inhibited cell migration and invasion and inverted EMT triggered by TGF-β1. LINC00963 downregulation also inhibited tumorigenesis in nude mice. In addition, results show that LINC00963 is a cytoplasmic lncRNA that shares the miRNA response elements (MREs) of miR-378g with CHI3L1, which is confirmed by a luciferase reporter assay and AGO2-dependent RNA immunoprecipitation (RIP).

CONCLUSION

On the whole, our results demonstrate an explicit oncogenic role of LINC00963 in ovarian cancer tumorigenesis via competition with miR-378g, suggesting a new regulatory mechanism of LINC00963 and providing a potential therapeutic target for ovarian cancer patients.

Saga of Mcl-1: regulation from transcription to degradation

The members of the Bcl-2 family are the central regulators of various cell death modalities. Some of these proteins contribute to apoptosis, while others counteract this type of programmed cell death, thus balancing cell demise and survival. A disruption of this balance leads to the development of various diseases, including cancer. Therefore, understanding the mechanisms that underlie the regulation of proteins of the Bcl-2 family is of great importance for biomedical research. Among the members of the Bcl-2 family, antiapoptotic protein Mcl-1 is characterized by a short half-life, which renders this protein highly sensitive to changes in its synthesis or degradation. Hence, the regulation of Mcl-1 is of particular scientific interest, and the study of Mcl-1 modulators could aid in the understanding of the mechanisms of disease development and the ways of their treatment. Here, we summarize the present knowledge regarding the regulation of Mcl-1, from transcription to degradation, focusing on aspects that have not yet been described in detail.

RPSAP52 lncRNA Inhibits p21Waf1/CIP Expression by Interacting With the RNA Binding Protein HuR

Long noncoding RNAs have been recently demonstrated to have an important role in fundamental biological processes, and their deregulated expression has been found in several human neoplasias. Our group has recently reported a drastic overexpression of the long noncoding RNA (lncRNA) RPSAP52 (ribosomal protein SA pseudogene 52) in pituitary adenomas. We have shown that this lncRNA increased cell proliferation by upregulating the expression of the chromatinic proteins HMGA1 and HMGA2, functioning as a competing endogenous RNA (ceRNA) through competitively binding to microRNA-15a (miR-15a), miR-15b, and miR-16. The aim of this work was to identify further mechanisms by which RPSAP52 overexpression could contribute to the development of pituitary adenomas. We investigated the involvement of RPSAP52 in the modulation of the expression of cell cycle-related genes, such as p21Waf1/CIP, whose deregulation plays a critical role in pituitary cell transformation. We report that RPSAP52, interacting with the RNA binding protein HuR (human antigen R), favors the delocalization of miR-15a, miR-15b, and miR-16 on the cyclin-dependent kinase inhibitor p21Waf1/CIP1 that, accordingly, results in downregulation in pituitary adenomas. A RNA immunoprecipitation sequencing (RIPseq) analysis performed on cells overexpressing RPSAP52 identified 40 messenger RNAs (mRNAs) enriched in Argonaute 2 (AGO2) immunoprecipitated samples. Among them, we focused on GAS8 (growth arrest-specific protein 8) gene. Consistently, GAS8 expression was downregulated in all the analyzed pituitary adenomas with respect to normal pituitary and in RPSAP52-overepressing cells, supporting the role of RPSAP52 in addressing genes involved in growth inhibition and cell cycle arrest to miRNA-induced degradation. This study unveils another RPSAP52-mediated molecular mechanism in pituitary tumorigenesis.

Long non-coding RNA linc00152 acting as a promising oncogene in cancer progression

The incidence and mortality rate of cancer continues to gradually increase, although considerable research effort has been directed at elucidating the molecular mechanisms underlying biomarkers responsible for tumorigenesis. Accumulated evidence indicates that the long non-coding RNAs (lncRNAs), which are transcribed but not translated into functional proteins, contribute to cancer development. Recently, linc00152 (an lncRNA) was identified as a potent oncogene in various cancer types, and shown to be involved in cancer cell proliferation, invasiveness, and motility by sponging tumor-suppressive microRNAs acting as a competing endogenous RNA, binding to gene promoters acting as a transcriptional regulator, and binding to functional proteins. In this review, we focus on the oncogenic role of linc00152 in tumorigenesis and provided an overview of recent clinical studies on the effects of linc00152 expression in human cancers.

Long Non-Coding RNA LINC00152 Regulates Cell Proliferation, Migration And Invasion In Esophageal Squamous Cell Carcinoma Via miR-107/Rab10 Axis

Background

Esophageal squamous cell carcinoma (ESCC) is a common  malignant tumor in East Asia. Emerging evidence indicated that long intergenic non-coding RNA 152 (LINC00152) acts as an oncogene in many types of cancers including ESCC. This study aims to identify the biological mechanisms of LINC00152 in ESCC, hinting for new therapeutic target for ESCC patients.

Methods

The levels of LINC00152, microRNA-107 (miR-107) and Ras-related protein Rab-10 (Rab10) were measured in ESCC tissues and cells using qRT-PCR. The protein level of Rab10 was measured by Western blot assay. The putative target of LINC00152 or miR-107 was searched using starBase v2.0 and TargetScan online databases, and dual-luciferase reporter assay was conducted to detect the interaction between miR-107 and LINC00152 or Rab10. The cell viability was monitored by CCK8 assay, and the abilities of migration and invasion were assessed by Transwell assay, respectively. The mice model experiments were constructed to affirm the biological role of LINC00152 in vivo.

Results

LINC00152, Rab10 was significantly upregulated, and miR-107 was strikingly down-regulated in ESCC tissues and cell lines (TE-1 and KYSE30). LINC00152 was verified as a sponge for miR-107, and Rab10 was a direct target of miR-107. LINC00152 depletion decreased cell viability and abilities of migration and invasion by regulating miR-107 in vitro and blocked xenograft tumor growth in vivo. The overexpression of miR-107 reduced cell viability and the abilities of migration and invasion by modulating Rab10. LINC00152 positively regulated Rab10 expression by sponging miR-107.

Conclusion

In this study, we found that LINC00152 modulated Rab10 to promote cell proliferation, migration and invasion in ESCC by sponging miR-107. This new regulatory network may provide a novel therapeutic target for ESCC patients.

Knockdown of long non-coding RNA LINC00152 increases cisplatin sensitivity in ovarian cancer cells

Drug resistance severely limits the effectiveness of chemotherapeutic treatment in ovarian cancer. The present study aimed to investigate the role of long non-coding RNA LINC00152 (LINC00152) in the cisplatin resistance of ovarian cancer. The expression level of LINC00152 was significantly increased in the ovarian cancer CoC1 and CoC1/DDP cell lines compared with the normal ovarian IOSE-80 cell line. To further investigate the function of LINC00152, small interfering RNAs (siRNAs) targeting LINC00152 were transfected into COC1 and COC1/DDP cells, which were subsequently treated with varying concentrations of cisplatin. The results revealed that LINC00152 silencing increased the apoptotic rates and enhanced the chemosensitivity of CoC1 and CoC1/DDP cells to cisplatin. Furthermore, downregulation of LINC00152 significantly decreased Bcl-2, and increased Bax and cleaved caspase-3 expression levels. Additionally, LINC00152 silencing decreased the expression of multidrug resistance-associated gene 1 (MDR1), multidrug resistance-associated protein 1 (MRP1) and glutathione S-transferase π (GSTπ). Collectively, the data demonstrated that LINC00152 knockdown increased the chemosensitivity of epithelial ovarian cancer cells to cisplatin by increasing apoptosis and decreasing the expression levels of MDR1, MRP1 and GSTπ.

Correlation of LAMA3 with onset and prognosis of ovarian cancer

Correlation of laminin subunit α3 (LAMA3) gene with onset and prognosis of ovarian cancer was investigated. In total, 210 ovarian cancer patients who received surgical resection in West China Second Hospital from March 2011 to March 2013 were randomly selected, and another 160 non-ovarian cancer patients who needed ovariectomy were also selected. The relative expression of LAMA3 gene was compared via quantitative polymerase chain reaction (qPCR) in carcinoma tissues, para-carcinoma tissues and non-carcinoma normal tissues in ovarian cancer patients. The methylation level was compared among the above three tissue types. The correlation between the mutation site rs12373237 in LAMA3 gene and onset was analyzed. The expression of laminin in ovarian cancer was detected using immunohistochemistry. Moreover, the 5-year survival rate after operation was recorded and the survival curve was plotted. The expression level of LAMA3 was lower in carcinoma tissues than those in normal tissues and para-carcinoma tissues (P<0.05). The methylation degree was lower in para-carcinoma tissues and normal tissues than that in carcinoma tissues (P<0.05). The CC homozygous mutation of rs12373237 was highly correlated with the onset of ovarian cancer (OR=4.333, P=0.028). The expression of LAMA3 was classified via immunohistochemistry, and the number in high-expression group (63.8%) was larger than that in low-expression group (36.2%) (P<0.05). According to the analysis of 5-year survival rate, the recurrence-free survival rate and overall survival rate in LAMA3 high-expression group were significantly higher than those in LAMA3 low-expression group (P<0.05). The expression level and base mutation of LAMA3 gene can change the level of laminin, which have a certain influence on the onset and prognosis of ovarian cancer.

Identify CRNDE and LINC00152 as the key lncRNAs in age-related degeneration of articular cartilage through comprehensive and integrative analysis

Background

Osteoarthritis (OA) is one of the most important age-related degenerative diseases, and the leading cause of disability and chronic pain in the aging population. Recent studies have identified several lncRNA-associated functions involved in the development of OA. Because age is a key risk factor for OA, we investigated the differential expression of age-related lncRNAs in each stage of OA.

Methods

Two gene expression profiles were downloaded from the GEO database and differentially expressed genes (DEGs) were identified across each of the different developmental stages of OA. Next, gene ontology (GO) functional and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed to annotate the function of the DEGs. Finally, a lncRNA-targeted DEG network was used to identify hub-lncRNAs.

Results

A total of 174 age-related DEGs were identified. GO analyses confirmed that age-related degradation was strongly associated with cell adhesion, endodermal cell differentiation and collagen fibril organization. Significantly enriched KEGG pathways associated with these DEGs included the PI3K–Akt signaling pathway, focal adhesion, and ECM–receptor interaction. Further analyses via a protein–protein interaction (PPI) network identified two hub lncRNAs, CRNDE and LINC00152, involved in the process of age-related degeneration of articular cartilage. Our findings suggest that lncRNAs may play active roles in the development of OA. Investigation of the gene expression profiles in different development stages may supply a new target for OA treatment.

Comprehensive analysis of differentially expressed profiles and reconstruction of a competing endogenous RNA network in papillary renal cell carcinoma

Long noncoding RNAs (lncRNAs) function as competing endogenous RNAs (ceRNAs). ceRNA networks may serve important roles in various tumors, as demonstrated by an increasing number of studies; however, papillary renal cell carcinoma (PRCC)-associated ceRNA networks mediated by lncRNAs remain unknown. Increased knowledge of ceRNA networks in PRCC may aid the identification of novel targets and biomarkers in the treatment of PRCC. In the present study, a comprehensive investigation of mRNA, lncRNA, and microRNA (miRNA) expression in PRCC was conducted using sequencing data from The Cancer Genome Atlas. Differential expression (DE) profiles of mRNAs, lncRNAs and miRNAs were evaluated, with 1,970 mRNAs, 1,201 lncRNAs and 96 miRNAs identified as genes with significantly different expression between PRCC and control paracancerous tissues. Based on the identified DEmRNAs, a protein-protein interaction network was generated using the STRING database. Furthermore, a ceRNA network for PRCC was determined using a targeted assay combined with the DE of miRNAs, mRNAs and lncRNAs, enabling the identification of important lncRNA-miRNA and miRNA-mRNA pairs. Analysis of the ceRNA network led to the extraction of a subnetwork and the identification of lncRNA maternally expressed 3 (MEG3), lncRNA PWRN1, miRNA (miR)-508, miR-21 and miR519 as important genes. Reverse transcription-quantitative polymerase chain reaction analysis was conducted to validate the results of the bioinformatics analyses; it was revealed that lncRNA MEG3 expression levels were downregulated in PRCC tumor tissues compared with adjacent non-tumor tissues. In addition, survival analysis was conducted to investigate the association between identified genes and the prognosis of patients with PRCC, indicating the potential involvement of 13 mRNAs, 15 lncRNAs and six miRNAs. In conclusion, the present study may improve understanding of the regulatory mechanisms of ceRNA networks in PRCC and provide novel insight for future studies of prognostic biomarkers and potential therapeutic targets.

Linc00152 knockdown inactivates the Akt/mTOR and Notch1 pathways to exert its anti-hemangioma effect

AIMS

Infantile hemangioma (IH) is one of the most common benign vascular tumors occurred in infants. Linc00152 is a kind of long non-coding RNAs (lncRNAs) and acts as a tumor oncogene. Recent study reported that Linc00152 is highly expressed in clinical IH tissues. However, the exact biological roles have not yet been investigated. The aim of the present study was to investigate the oncogenic roles of Linc00152 in IH and the underlying mechanism in vitro.

MAIN METHODS

The expressions of Linc00152 in IH tissues and hemangioma-derived endothelial cells (HemECs) were determined using quantitative real time-PCR (qRT-PCR) analysis. The expressions of Akt/mTOR and Notch1 pathways related proteins were detected using western blot analysis. Cell proliferation was assessed by detecting Ki67 expression and CCK-8 assay. Cell apoptosis was evaluated by detecting apoptotic rate, caspase-3/7 activity, and Bcl-2 and Bax expression.

KEY FINDINGS

The results demonstrated Linc00152 was up-regulated in clinical IH tissues and HemECs. Knockdown of Linc00152 in HemECs suppressed the activation of Akt/mTOR and Notch1 signaling pathways and caused reduction in cell proliferation and Ki67 expression in HemECs. Besides, Linc00152 knockdown resulted in a significant increase in apoptotic rate, caspase-3/7 activity, and Bax expression level, as well as a decrease in Bcl-2 expression level. However, the effects of Linc00152 knockdown on cell proliferation and apoptosis were mitigated by overexpression of Akt or Notch1.

SIGNIFICANCE

Knockdown of Linc00152 suppressed HemECs proliferation and induced apoptosis via inhibiting Akt/mTOR and Notch1 signaling pathways.

MALAT1 sponges miR-106b-5p to promote the invasion and metastasis of colorectal cancer via SLAIN2 enhanced microtubules mobility

Background

The low expression of miR93/25 (members of miR-106b~25 cluster) promoted the invasion and metastasis of colon cancer cells, which predicted poor survival. However, the role of miR-106b-5p, the member of miR-106b~25 cluster, in colorectal cancer (CRC) remains unclear.

Methods

Bioinformatics methods were used to predict the potential pairs of lncRNA-miRNA-mRNA. In situ hybridization and qPCR were used to evaluate the expression of MALAT1 and miR-106b-5p in the paraffin-embedded normal and CRC tissues. Kaplan–Meier analysis with the log-rank test was used for survival analyses. Immunohistochemistry staining was applied to investigate the expression of SLAIN2. Fluorescence recovery after photobleaching assay was applied to observe the microtubule (MT) mobility. In vitro and in vivo invasion and metastasis assays were used to explore the function of MALAT1/miR-106b-5p/SLAIN2 in the progression of CRC.

Findings

miR-106b-5p was identified as a suppressor in CRC. Functionally, ectopic or silencing the expression of miR-106b-5p inhibited or promoted the invasion and metastasis of CRC cells in vitro and in vivo. The long non-coding RNA MALAT1 regulated the miR-106b-5p expression and further mediated the mobility of SLAIN2-related MTs by functioning as a competing endogenous RNA in vitro and in vivo, which resulted in the progression of CRC. Clinically, low miR-106b-5p expression predicted poor survival of CRC patients, especially in combination with high MALAT1/ SLAIN2 expression.

Interpretation

miR-106b-5p served as a suppressor in combination with MALAT1/miR-106b-5p/SLAIN2, which might be a group of potential prognostic biomarkers in the prognosis of CRC.

Fund

This work was supported by National Program Project for Precision Medicine in National Research and Development Plan of China (2016YFC0905300), National Natural Science Foundation of China (81572930), National Key Research and Development Program of the Ministry of Science and Technology of China (2016YFC0905303, 2016YFC1303200), Beijing Science and Technology Program (D17110002617004), Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences (2018PT32012), CAMS Innovation Fund for Medical Sciences (CIFMS) (2016-I2M-1-001), Incentive Fund for Academic Leaders of Oncology Hospital, Chinese Academy of Medical Sciences (RC2016003), and Beijing Hope Run Special Fund from Cancer Foundation of China (LC2017A19). The project of Shanghai Jiaotong Univversity (YG2017QN30).

LINC00152 facilitates tumorigenesis in esophageal squamous cell carcinoma via miR-153-3p/FYN axis

Long non-coding RNAs (LncRNAs) have been found to be associated with the biological behaviors of human cancers. LINC00152 is reported as an oncogene in many kinds of malignancies. However, the functions and mechanisms of LINC00152 involved in esophageal squamous cell carcinoma (ESCC) remain elusive. Our results revealed that LINC00152 expression was up-regulated in ESCC, and correlated with advanced TNM stage, lymph node metastasis, and poor prognosis of ESCC patients. Functionally, LINC00152 knockdown suppressed proliferation, decreased colony forming ability, and induced apoptosis in ESCC cells. Mechanically, LINC00152 functioned as a competing endogenous RNA (ceRNA) to sponge miR-153-3p, thereby facilitating its downstream target FYN. Moreover, miR-153-3p-mediated tumor-suppressive effects were partly reversed following LINC00152 overexpression. Also, FYN knockdown displayed a similar anti-cancerous role in ESCC cells. Taken together, LINC00152 contributed to ESCC progression by down-regulating miR-153-3p and promoting FYN expression, uncovering a novel LINC00152/miR-153-3p/FYN regulatory pathway in ESCC.

Long Noncoding RNA LINC00152 Facilitates the Leukemogenesis of Acute Myeloid Leukemia by Promoting CDK9 Through miR-193a

The vital role of long noncoding RNAs (lncRNAs) on the acute myeloid leukemia (AML) has been increasingly recognized. This study aims to explore the unknown function of lncRNA LINC00152 in the leukemogenesis of AML. LINC00152 is determined to be upregulated in the AML samples, and the overexpression of LINC00152 is also authenticated in the advanced French-American-British (FAB) AML patients and closely correlated with the poor outcome of AML patients. The functional experiments state that knockdown of LINC00152 suppresses the proliferation, accelerates the apoptosis, and induces the cycle arrest of AML cells. The mechanical experiments state that LINC00152 and CDK9 were both targeted by miR-193a with the complementary binding sites at 3'-UTR. Moreover, in the rescue experiments, the enhanced LINC00152 expression could regain the suppression of tumor behavior induced by LINC00152 knockdown. In conclusion, this research reveals the important role of lncRNA LINC00152 in the AML leukemogenesis through targeting miR-193a/CDK9 axis. This finding could indicate the important pathogenesis of ncRNA and the vital roles of epigenetic regulation.

Long non-coding RNA LINC00662 promotes proliferation and migration in oral squamous cell carcinoma

Background

Although increasing evidence has demonstrated important roles for long non-coding RNAs (lncRNAs) in cancer development, their functions in oral squamous cell carcinoma (OSCC) growth remain largely unknown. Therefore, we aimed to investigate the role of LINC00662 in OSCC.

Methods

The expression of LINC00662 in 61 OSCC tissues and four OSCC cell lines were detected by quantitative reverse-transcription polymerase chain reaction (qRT-PCR). Cell proliferation was detected using Cell Counting Kit-8 (CCK-8) and EdU staining methods. Migration and invasion abilities were analyzed using transwell and wound healing assay. Cell cycle distribution and apoptosis rate were evaluated by flow cytometry. Western blot method was performed to detect protein expression.

Results

We found that the expression of LINC00662 was significantly increased in OSCC tissues, and a higher expression of LINC00662 was detected in larger tumor size, higher stage tumors and with lymph node metastasis. Moreover, overexpression of LINC00662 induced OSCC cell proliferation, increased migration and invasion abilities, and suppressed cell apoptosis. Knockdown of LINC00662 decreased the proliferation, migration, and invasion abilities of OSCC cell, and induced apoptosis. Furthermore, LINC00662 regulated the Wnt/β-catenin pathway.

Conclusion

Our data indicate that LINC00662 may represent a novel indicator of OSCC and may be a potential therapeutic target for diagnosis and therapy.

Linc00662 Promotes Tumorigenesis and Progression by Regulating miR-497-5p/AVL9 Axis in Colorectal Cancer

BACKGROUND

Recently, multiple lines of evidence have demonstrated that linc00662 serves as an oncogene in various cancers. However, the exact mechanism of oncogenesis mediated by linc00662 in colorectal cancer (CRC) remains unknown. In this study, we aimed to explore the biological role of linc00662 in the regulation of CRC progression.

METHODS

Both gene expression omnibus (GEO) and the cancer genome atlas (TCGA) datasets were used to evaluate the expression of linc00662. RT-qPCR was used to analyze the expression of linc00662, miR-497-5p, and AVL9 in CRC clinical samples and cell lines. Cell Counting Kit-8 (CCK-8), flow cytometry, transwell assay, and xenograft model were used to investigate the effect of linc00662 on CRC cell proliferation, cell cycle, and metastasis. Western blot analysis was used to analyze the expression of the epithelial-mesenchymal transition (EMT)-associated markers. Furthermore, bioinformatics analysis and mechanism assays were used to elucidate the underlying mechanism. Dual-luciferase reporter assays were used to analyze the regulatory relationships among linc00662, miR-497-5p, and AVL9.

RESULTS

In this study, we found that the expression of linc00662 was significantly upregulated in CRC tissues compared to normal tissues and positively correlated with tissue differentiation, T stage, and lymphatic metastasis. Further, our data showed that the expression of linc00662 was positively associated with lymph node metastasis, TMN stage, and poor-moderate differentiation. Patients with higher linc00662 expression level were more likely to have poorer overall survival. Knockdown of linc00662 inhibited CRC cell growth, induced cell apoptosis, triggered cell cycle arrest at G2/M phase, and suppressed cell migration and invasion through regulating the EMT pathway. Further, mechanistic studies revealed that knockdown of linc00662 significantly reduced the expression of AVL9, a direct target of miR-497-5p.

CONCLUSIONS

Linc00662 was significantly upregulated in CRC, and mediated CRC progression and metastasis by competing with miR-497-5p to modulate the expression of AVL9. Therefore, our result sheds light on the potential application of linc00662 in CRC diagnosis and therapy.

Long noncoding RNA CYTOR sponges miR-195 to modulate proliferation, migration, invasion and radiosensitivity in nonsmall cell lung cancer cells

Nonsmall cell lung cancer (NSCLC) is one of the most frequent malignancies worldwide. Long noncoding RNAs (LncRNAs) play critical roles in cancer initiation and progression. Previous studies have demonstrated that overexpression of cytoskeleton regulator RNA (CYTOR) predicates poor prognosis and promotes tumor progression. However, the functional roles and underlying mechanism of CYTOR in NSCLC remain unknown. In the present study, we found that CYTOR promoted cell proliferation, migration and invasion ability, and induced radioresistance in NSCLC cells. Mechanistically, CYTOR could directly interact with miR-195 and increase its targets. Thus, CYTOR played an oncogenic role in NSCLC progression through sponging miR-195. Together, our study elucidates the role of CYTOR as a microRNA sponge in NSCLC, and CYTOR may be used as a promising therapeutic target for NSCLC treatment.

LncRNAs in ovarian cancer

Ovarian cancer is one of the most common gynecologic malignancies and has a poor prognosis. Recently, long noncoding RNAs (lncRNAs) have been identified as key regulators of cancer development. Studies have shown that the dysregulation of lncRNAs is frequently observed in ovarian cancer and greatly contributes to malignant phenotypical changes. In this review, we provide perspectives on the involvement of lncRNAs in the proliferation, apoptosis, cell cycle, migration, invasion, metastasis and drug resistance of ovarian cancer based on recent discoveries. Then, we discuss the role of lncRNAs in predicting the prognosis of ovarian cancer. Finally, we provide insight into the potential of lncRNAs for evaluating the diagnosis and prognosis of ovarian cancer.

SATB1 3'-UTR and lncRNA-UCA1 competitively bind to miR-495-3p and together regulate the proliferation and invasion of gastric cancer

High expression of special AT-rich-binding protein 1 (SATB1) correlates with the advanced TNM stage and short overall and recurrence-free survival of gastric cancer (GC). A bioinformatic analysis revealed that SATB1 3'-untranslated region (3'-UTR) and long noncoding RNA UCA1 (lncRNA-UCA1) might competitively bind to microRNA-495-3p (miR-495-3p). Interestingly, lncRNA-UCA1 is also an important contributor to GC. The current study aimed to demonstrate the potential interaction among SATB1/miR-495-3p/lncRNA-UCA1 network and their effects on GC proliferation and invasion. The expression in GC and paracancerous normal tissues were assessed using real-time polymerase chain reaction and Western blot analysis. Luciferase reporter, RNA pull-down, and transfection assays were performed to determine the interaction among SATB1/miR-495-3p/lncRNA-UCA1 network in GC cells. GC proliferation and invasion were evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, transwell invasion, and colony formation assays. Results showed higher expression of SATB1 and lncRNA-UCA1 but lower miR-495-3p expression in GC than in the normal tissues. In luciferase reporter assay, miR-495-3p bound to three seed sequences in SATB1 3'-UTR but only one in lncRNA-UCA1. SATB1 knockdown increased the combination of miR-495-3p with lncRNA-UCA1 but decreased lncRNA-UCA1 expression. Decreased lncRNA-UCA1 was also observed with the mimics increased miR-495-3p. These data suggested that SATB1 3'-UTR functions as a competing endogenous RNA of miR-495-3p and positively regulates lncRNA-UCA1. LncRNA-UCA1 knockdown only decreased SATB1 expression in MKN-45 cells but not in BGC-823 cells, which suggested that the regulatory effect of lncRNA-UCA1 on SATB1 by sponging miR-495-3p is cell-dependent. This study further identified that SATB1/miR-495-3p/lncRNA-UCA1 network is implicated in GC proliferation and invasion. The current study firstly revealed that SATB1 interacts with miR-495-3p/lncRNA-UCA1 network, whereby enhancing GC proliferation and invasion.