Over Expression of Long Non-Coding RNA PANDA Promotes Hepatocellular Carcinoma by Inhibiting Senescence Associated Inflammatory Factor IL8

Non-coding RNAs participate in interactions between senescence and gastrointestinal cancers

Relationships between cellular senescence and gastrointestinal cancers have gained prominence in recent years. The currently accepted theory suggests that cellular senescence and cancer occurrence exhibit "double-edged sword" effects. Cellular senescence is related to cancer via four "meta-hallmarks" i.e., genomic instability, epigenetic alterations, chronic inflammation, and dysbiosis, along with two "antagonistic hallmarks" i.e., telomere attrition and stem cell exhaustion. These relationships are characterized by both agonistic and antagonistic elements, but the existence of an intricate dynamic balance remains unknown. Non-coding RNAs (ncRNAs) have vital roles in post-transcriptional regulation, but how they participate in agonistic and antagonistic relationships between cellular senescence and gastrointestinal cancers remains to be fully investigated. In this article, we systematically review how ncRNAs (including microRNAs (miRNAs), long ncRNAs (lncRNAs), and circularRNAs (circRNAs)) participate in interactions between cellular senescence and gastrointestinal cancers. Our aim is to elucidate a triangular relationship between "ncRNAs-senescence-gastrointestinal cancers" which considered these three elements as an equal important standing. We are keen to identify prognostic or therapeutic targets for gastrointestinal cancers from, i.e., aging-related ncRNAs, or discover novel strategies to treat and manage in the elderly. We seek to clarify complex relationships where ncRNAs participate in "senescence-gastrointestinal cancers" interactions.

Long non-coding RNAs: roles in cellular stress responses and epigenetic mechanisms regulating chromatin

Most of the genome is transcribed into RNA but only 2% of the sequence codes for proteins. Non-coding RNA transcripts include a very large number of long noncoding RNAs (lncRNAs). A growing number of identified lncRNAs operate in cellular stress responses, for example in response to hypoxia, genotoxic stress, and oxidative stress. Additionally, lncRNA plays important roles in epigenetic mechanisms operating at chromatin and in maintaining chromatin architecture. Here, we address three lncRNA topics that have had significant recent advances. The first is an emerging role for many lncRNAs in cellular stress responses. The second is the development of high throughput screening assays to develop causal relationships between lncRNAs across the genome with cellular functions. Finally, we turn to recent advances in understanding the role of lncRNAs in regulating chromatin architecture and epigenetics, advances that build on some of the earliest work linking RNA to chromatin architecture.

Hypomethylation at PANDAR promoter progressively induces senescence in adipocyte precursor cells in subjects with obesity and type 2 diabetes

The risk of developing type 2 diabetes (T2D) is heterogeneous among individuals with obesity. Functional decline of adipocyte precursor cells (APCs) and accumulation of senescent cells in the subcutaneous adipose tissue contributes to the progression toward T2D. LncRNAs regulate cell senescence and may be implicated in determining this abnormality in APCs. Here, we report that APCs from individuals with obesity show a gradual increase in multiple senescence markers, which worsens in parallel with the progression from normal glucose tolerance (NGT) to impaired glucose tolerance (IGT) or T2D. Transcriptomic analysis identified PANDAR as the top-ranked lncRNA differentially expressed in APCs from individuals with obesity and T2D and non-obese subjects. Q-PCR confirmed PANDAR up-regulation in APCs from individuals with obesity, at progressively increased levels in those who developed, respectively, IGT and T2D. Bisulfite sequencing and luciferase assays revealed that, in parallel with glucose tolerance deterioration, the -1317 CpG at the PANDAR promoter became hypo-methylated in obesity, resulting in enhanced PANDAR induction by p53. PANDAR silencing in senescent APCs from individuals with obesity and T2D caused repression of senescence programs and cell cycle re-entry. PANDAR transcription in white blood cells (WBCs) mirrored that in APCs. Also, individuals with obesity exhibited rescue of PANDAR transcription in WBCs following bariatric surgery, accompanied by enhanced methylation at the regulatory PANDAR -1317 CpG. In conclusion, PANDAR dysregulation is a newly identified mechanism determining the early senescence of APCs from individuals with obesity, which worsens along the progression toward T2D. In the future, PANDAR targeting may represent a valuable strategy to delay this progression.

A novel aging-associated lncRNA signature for predicting prognosis in osteosarcoma

Osteosarcoma (OS) is one of the most prevalent bone tumors in adolescents, and the correlation between aging and OS remains unclear. Currently, few accurate and reliable biomarkers have been determined for OS prognosis. To address this issue, we carried out a detailed bioinformatics analysis based on OS with data from the Cancer Genome Atlas data portal and Human Aging Genomic Resources database, as well as in vitro experiments. A total of 88 OS samples with gene expression profiles and corresponding clinical characteristics were obtained. Through univariate Cox regression analysis and survival analysis, 10 aging-associated survival lncRNAs (AASRs) were identified to be associated with the overall survival of OS patients. Based on the expression levels of the 10 AASRs, the OS patients were classified into two clusters (Cluster A and Cluster B). Cluster A had a worse prognosis, while Cluster B had a better prognosis. Then, 5 AASRs were ultimately included in the signature through least absolute shrinkage and selection operator-Cox regression analysis. Kaplan‒Meier survival analysis verified that the high-risk group exhibited a worse prognosis than the low-risk group. Furthermore, univariate and multivariate Cox regression analyses confirmed that the riskScore was an independent prognostic factor for OS patients. Subsequently, we discovered that the risk signature was correlated with the properties of the tumor microenvironment and immune cell infiltration. Specifically, there was a positive association between the risk model and naïve B cells, resting dendritic cells and gamma delta T cells, while it was negatively related to CD8+ T cells. Finally, in vitro experiments, we found that UNC5B-AS1 inhibited OS cells from undergoing cellular senescence and apoptosis, thereby promoting OS cells proliferation. In conclusion, we constructed and verified a 5 AASR-based signature, that exhibited excellent performance in evaluating the overall survival of OS patients. In addition, we found that UNC5B-AS1 might inhibit the senescence process, thus leading to the development and progression of OS. Our findings may provide novel insights into the treatment of OS patients.

Elsayed A, López-Berestein G, Amero P, Rodríguez-Aguayo C. An Overview of the Immune Modulatory Properties of Long Non-Coding RNAs and Their Potential Use as Therapeutic Targets in Cancer

Long non-coding RNAs (lncRNAs) play pivotal roles in regulating immune responses, immune cell differentiation, activation, and inflammatory processes. In cancer, they are gaining prominence as potential therapeutic targets due to their ability to regulate immune checkpoint molecules and immune-related factors, suggesting avenues for bolstering anti-tumor immune responses. Here, we explore the mechanistic insights into lncRNA-mediated immune modulation, highlighting their impact on immunity. Additionally, we discuss their potential to enhance cancer immunotherapy, augmenting the effectiveness of immune checkpoint inhibitors and adoptive T cell therapies. LncRNAs as therapeutic targets hold the promise of revolutionizing cancer treatments, inspiring further research in this field with substantial clinical implications.

LncRNAs-associated to genomic instability: A barrier to cancer therapy effectiveness

Although a large part of the genome is transcribed, only 1.9% has a protein-coding potential; most of the transcripts are non-coding RNAs such as snRNAs, tRNAs, and rRNAs that participate in mRNA processing and translation. In addition, there are small RNAs with a regulatory role, such as siRNAs, miRNAs, and piRNAs. Finally, the long non-coding RNAs (lncRNAs) are transcripts of more than 200 bp that can positively and negatively regulate gene expression (both in cis and trans), serve as a scaffold for protein recruitment, and control nuclear architecture, among other functions. An essential process regulated by lncRNAs is genome stability. LncRNAs regulate genes associated with DNA repair and chromosome segregation; they are also directly involved in the maintenance of telomeres and have recently been associated with the activity of the centromeres. In cancer, many alterations in lncRNAs have been found to promote genomic instability, which is a hallmark of cancer and is associated with resistance to chemotherapy. In this review, we analyze the most recent findings of lncRNA alterations in cancer, their relevance in genomic instability, and their impact on the resistance of tumor cells to anticancer therapy.

Interplays between non-coding RNAs and chemokines in digestive system cancers

Within tumors, chemokines and their cognate receptors are expressed by infiltrated leukocytes, cancerous cells, and related cells of stroma, like tumor-associated fibroblasts and tumor-associated macrophages. In malignancies, the altered expression of chemokines/chemokine receptors governs leukocyte infiltration and activation, epithelial-mesenchymal transition (EMT), cancer cell proliferation, angiogenesis, and metastasis. Non-coding RNAs (ncRNAs) contribute to multiple physiological and pathophysiological processes. Some miRNAs can exert anti-tumorigenic activity in digestive system malignancies by repressing the expression of tumor-promoting chemokines/chemokine receptors or by upregulating tumor-suppressing chemokines/chemokine receptors. However, many miRNAs exert pro-tumorigenic activity by suppressing the expression of chemokines/chemokine receptors or by upregulating tumor-promoting chemokines/chemokine receptors. LncRNA and circRNAs also exert pro- and anti-tumorigenic effects by targeting downstream miRNAs influencing the expression of tumor-promoting and tumor-suppressor chemokines/chemokine receptors. On the other side, some chemokines influence the expression of ncRNAs affecting tumor formation. The current review explains the communications between ncRNAs and chemokines/chemokine receptors in certain digestive system malignancies, such as gastric, colorectal, and pancreatic cancers and hepatocellular carcinoma to gain better insights into their basic crosstalk as well as possible therapeutic modalities.

Emerging Role of Non-Coding RNAs in Senescence

Senescence is defined as a gradual weakening of functional features of a living organism. Cellular senescence is a process that is principally aimed to remove undesirable cells by prompting tissue remodeling. This process is also regarded as a defense mechanism induced by cellular damage. In the course of oncogenesis, senescence can limit tumor progression. However, senescence participates in the pathoetiology of several disorders such as fibrotic disorders, vascular disorders, diabetes, renal disorders and sarcopenia. Recent studies have revealed contribution of different classes of non-coding RNAs in the cellular senescence. Long non-coding RNAs, microRNAs and circular RNAs are three classes of these transcripts whose contributions in this process have been more investigated. In the current review, we summarize the available literature on the impact of these transcripts in the cellular senescence.

Predictive Potentials of ZEB1-AS1 in Colorectal Cancer Prognosis and Their Correlation with Immunotherapy

Background

CRC is the third most common cancer globally. The tumor immune microenvironment is closely associated with the overexpressed lncRNA ZEB1-AS1. However, in individuals with CRC, the ZEB1-AS1 gene's ability to predict immune response is a mystery.

Materials and Methods

The ZEB1-AS1 gene's prognostic potential was thoroughly investigated. We analyzed and included into the TCGA database all ZEB1-AS1 and ZEB1-AS1-related genes using LASSO-Cox regression. Researchers examined the link among ZEB1-AS1 and the tumor immune microenvironment, immune checkpoint, and tumor mutation burden (TMB) in CRC through the TCGA database. Using a predictive model, researchers were able to determine the link between ZEB1-AS1 and NUDT3 and CRC prognosis.

Result

According to our findings, individuals with reduced ZEB1-AS1 expression had a better prognosis in CRC. Based on the expression of two genes in the TCGA database, patients were divided into two cohorts. The B lymphocytes and macrophages are less likely to be recruited by tissues with a low-risk score. TMB and immunological checkpoints were shown to have a connection. Based on these genes, a predictive nomogram was built and confirmed, with a C-index of 0.78.

Conclusion

Prognostic models based on ZEB1-AS1 and ZEB1-AS1-related genes are more accurate for CRC patients when it comes to the prognosis and immune checkpoint responsiveness.

LINC00355 regulates p27KIP expression by binding to MENIN to induce proliferation in late-stage relapse breast cancer

Late-stage relapse (LSR) in patients with breast cancer (BC) occurs more than five years and up to 10 years after initial treatment and has less than 30% 5-year relative survival rate. Long non-coding RNAs (lncRNAs) play important roles in BC yet have not been studied in LSR BC. Here, we identify 1127 lncRNAs differentially expressed in LSR BC via transcriptome sequencing and analysis of 72 early-stage and 24 LSR BC patient tumors. Decreasing expression of the most up-regulated lncRNA, LINC00355, in BC and MCF7 long-term estrogen deprived cell lines decreases cellular invasion and proliferation. Subsequent mechanistic studies show that LINC00355 binds to MENIN and changes occupancy at the CDKN1B promoter to decrease p27Kip. In summary, this is a key study discovering lncRNAs in LSR BC and LINC00355 association with epigenetic regulation and proliferation in BC.

The various regulatory functions of long noncoding RNAs in apoptosis, cell cycle, and cellular senescence

Long noncoding RNAs (lncRNAs) are a group of noncoding cellular RNAs involved in significant biological phenomena such as differentiation, cell development, genomic imprinting, adjusting the enzymatic activity, regulating chromosome conformation, apoptosis, cell cycle, and cellular senescence. The misregulation of lncRNAs interrupting normal biological processes has been implicated in tumor formation and metastasis, resulting in cancer. Apoptosis and cell cycle, two main biological phenomena, are highly conserved and intimately coupled mechanisms. Hence, some cell cycle regulators can influence both programmed cell death and cell division. Apoptosis eliminates defective and unwanted cells, and the cell cycle enables cells to replicate themselves. The improper regulation of apoptosis and cell cycle contributes to numerous disorders such as neurodegenerative and autoimmune diseases, viral infection, anemia, and mainly cancer. Cellular senescence is a tumor-suppressing response initiated by environmental and internal stress factors. This phenomenon has recently attained more attention due to its therapeutic implications in the field of senotherapy. In this review, the regulatory roles of lncRNAs on apoptosis, cell cycle, and senescence will be discussed. First, the role of lncRNAs in mitochondrial dynamics and apoptosis is addressed. Next, the interaction between lncRNAs and caspases, pro/antiapoptotic proteins, and also EGFR/PI3K/PTEN/AKT/mTORC1 signaling pathway will be investigated. Furthermore, the effect of lncRNAs in the cell cycle is surveyed through interaction with cyclins, cdks, p21, and wnt/β-catenin/c-myc pathway. Finally, the function of essential lncRNAs in cellular senescence is mentioned.

The Impact of Long Non-Coding RNAs in the Pathogenesis of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is among the utmost deadly human malignancies. This type of cancer has been associated with several environmental, viral, and lifestyle risk factors. Among the epigenetic factors which contribute in the pathogenesis of HCC is dysregulation of long non-coding RNAs (lncRNAs). These transcripts modulate expression of several tumor suppressor genes and oncogenes and alter the activity of cancer-related signaling axes. Several lncRNAs such as NEAT1, MALAT1, ANRIL, and SNHG1 have been up-regulated in HCC samples. On the other hand, a number of so-called tumor suppressor lncRNAs namely CASS2 and MEG3 are down-regulated in HCC. The interaction between lncRNAs and miRNAs regulate expression of a number of mRNA coding genes which are involved in the pathogenesis of HCC. H19/miR-15b/CDC42, H19/miR-326/TWIST1, NEAT1/miR-485/STAT3, MALAT1/miR-124-3p/Slug, MALAT1/miR-195/EGFR, MALAT1/miR-22/SNAI1, and ANRIL/miR-144/PBX3 axes are among functional axes in the pathobiology of HCC. Some genetic polymorphisms within non-coding regions of the genome have been associated with risk of HCC in certain populations. In the current paper, we describe the recent finding about the impact of lncRNAs in HCC.

LINC00978 promotes hepatocellular carcinoma carcinogenesis partly via activating the MAPK/ERK pathway

Objective: To study the role of long non-coding RNA (lncRNA) LINC00978 in hepatocellular carcinoma (HCC) carcinogenesis.

Materials and methods: LINC00978 expression level was measured by reverse transcription quantitative real-time PCR (RT-qPCR) in HCC tissues and adjacent healthy liver tissues from 49 HCC patients. MTT assay, colony forming assay, and flow cytometry were performed to evaluate the effects of shRNA-mediated LINC00978 knockdown on HCC cell proliferation, cell cycle progression, and apoptosis in vitro. Xenograft tumor model was performed to determine the effects of LINC00978 knockdown on HCC tumor growth in vivo. Western blot was used to assess the activation of signaling molecules in the apoptosis and mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathway.

Results: LINC00978 expression was significantly up-regulated in human HCC tissue relative to adjacent normal tissue, and LINC00978 high expression was correlated with poor HCC overall survival. LINC00978 was up-regulated in HCC cell lines. ShRNA-mediated LINC00978 knockdown significantly decreased HCC cell proliferation, and induced HCC cell cycle arrest and apoptosis in vitro. LINC00978 knockdown led to significant decrease in tumor xenograft size in vivo. Western blots revealed LINC00978 inhibition decreased ERK, p38, and c-Jun N-terminal kinase (JNK) phosphorylation in HCC cells.

Conclusions: LINC00978 is highly expressed in human HCC tissue and correlates with poor HCC prognosis. LINC00978 promotes HCC cell proliferation, cell cycle progression, and survival, partially by activating the MAPK/ERK pathway. Our findings partially elucidated the roles of LINC00978 in HCC carcinogenesis, and identified a therapeutic target for HCC.

Identification and validation of seven prognostic long non-coding RNAs in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is one of the most common malignancies worldwide, due to poor diagnosis and treatment. There is increasing evidence that demonstrates the involvement of long non-coding RNAs (lncRNAs) in carcinogenesis and cancer progression. Therefore, the aim of the present study was to explore potential lncRNA-associated features of patients with OSCC as a valuable and independent prognostic biomarker. A total of 268 lncRNA expression profiles and clinical patient information on OSCC were downloaded from The Cancer Genome Atlas database. The clinical information was exploited for prescreening, using Cox regression analysis, and differentially expressed lncRNAs (DElncRNAs) were identified using edgeR software. Using the 'caret' package, the datasets were categorized into test datasets and training datasets, respectively. Through bioinformatics, seven prognostic DElncRNAs were selected. Using the regression coefficients, a risk score based on the seven-DElncRNA signature was developed to assess the prognostic function of key DElncRNAs. According to the median risk score, patients were classified into high-risk and low-risk groups in the training and test datasets. Additionally, receiver operating characteristic (ROC) curve analysis was conducted to evaluate the sensitivity and specificity of the prognostic DElncRNAs, and the optimal cut-off point was obtained from ROC analysis. Based on the optimal cut-off point, the patients were also categorized into high-risk and low-risk groups. Notably, the optimal cut-off point was more sensitive than the median risk score, particularly in the test dataset. The Kaplan-Meier survival and log rank test analysis results indicated that the P-value, based on the optimal cut-off, was less than the median risk cut-off. Additionally, stratified analysis results revealed that the seven-DElncRNAs signature was also independent of OSCC age. Furthermore, the findings of the present study suggested that the seven-DElncRNA signature can be used as a potential prognostic indicator and may have important clinical significance in OSCC.

Roles of lncRNAs in cancer: Focusing on angiogenesis

Approximately 98% of the human genome consists of non-coding sequences that are classified into two classes by size: small non-coding RNAs (≤200 nucleotides) and long non-coding RNAs (≥200 nucleotides). Long non-coding RNAs (lncRNAs) are involved in various cellular events and act as guides, signals, decoys, and dynamic scaffolds. Due to their oncogenic and tumor suppressive roles, lncRNAs are important in cancer development and growth. LncRNAs play their roles by modulating cancer hallmarks, including DNA damage, metastasis, immune escape, cell stemness, drug resistance, metabolic reprogramming, and angiogenesis. Angiogenesis is vital for solid tumors which guarantees their growth beyond 2 mm³. Tumor angiogenesis is a complex process and is regulated through interaction between pro-angiogenic and anti-angiogenic factors within the tumor microenvironment. There are accumulating evidence that different lncRNAs regulate tumor angiogenesis. In this paper, we described the functions and mechanisms of lncRNAs in tumor angiogenesis.

Histone deacetylase 3 preferentially binds and collaborates with the transcription factor RUNX1 to repress AML1-ETO-dependent transcription in t(8;21) AML

In up to 15% of acute myeloid leukemias (AMLs), a recurring chromosomal translocation, termed t(8;21), generates the AML1-eight-twenty-one (ETO) leukemia fusion protein, which contains the DNA-binding domain of Runt-related transcription factor 1 (RUNX1) and almost all of ETO. RUNX1 and the AML1-ETO fusion protein are coexpressed in t(8;21) AML cells and antagonize each other's gene-regulatory functions. AML1-ETO represses transcription of RUNX1 target genes by competitively displacing RUNX1 and recruiting corepressors such as histone deacetylase 3 (HDAC3). Recent studies have shown that AML1-ETO and RUNX1 co-occupy the binding sites of AML1-ETO-activated genes. How this joined binding allows RUNX1 to antagonize AML1-ETO-mediated transcriptional activation is unclear. Here we show that RUNX1 functions as a bona fide repressor of transcription activated by AML1-ETO. Mechanistically, we show that RUNX1 is a component of the HDAC3 corepressor complex and that HDAC3 preferentially binds to RUNX1 rather than to AML1-ETO in t(8;21) AML cells. Studying the regulation of interleukin-8 (IL8), a newly identified AML1-ETO-activated gene, we demonstrate that RUNX1 and HDAC3 collaboratively repress AML1-ETO-dependent transcription, a finding further supported by results of genome-wide analyses of AML1-ETO-activated genes. These and other results from the genome-wide studies also have important implications for the mechanistic understanding of gene-specific coactivator and corepressor functions across the AML1-ETO/RUNX1 cistrome.

Noncoding RNAs in inflammation and colorectal cancer

Despite advanced clinical treatments, mortality in patients with metastatic colorectal cancer (CRC) remains high. Three critical determinants in CRC progression include the epithelial proliferation checkpoints, epithelial-to-mesenchymal transition (EMT) and inflammatory cytokines in the tumour microenvironment. Genes involved in these three processes are regulated at the transcriptional and post-transcriptional level. Recent studies revealed previously unappreciated roles of non-coding ribonucleic acids (ncRNAs) in modulating the proliferation checkpoints, EMT, and inflammatory gene expression in CRC. In this review, we will discuss the mechanisms underlying the roles of ncRNAs in CRC as well as examine future perspectives in this field. Better understanding of ncRNA biology will provide novel targets for future therapeutic development.

lncRNA-Triggered Macrophage Inflammaging Deteriorates Age-Related Diseases

Aging and age-related diseases (ARDs) share basic mechanisms largely involving inflammation. A chronic, low-grade, subclinical inflammation called inflammaging occurs during aging. Autophagy defects, oxidative stresses, senescence-associated secretory phenotypes (SASPs), and DNA damage generally contribute to inflammaging and are largely regulated by numerous lncRNA through two-level vicious cycles disrupting cellular homeostasis: (1) inflammaging and the cellular senescence cascade and (2) autophagy defects, oxidative stress, and the SASP cascade. SASPs and inflammasomes simultaneously cause inflammaging. This review discusses the involvement of macrophage inflammaging in various ARDs and its regulation via lncRNA. Among macrophages, this phenomenon potentially impairs its immunosurveillance and phagocytosis mechanisms, leading to decreased recognition and clearance of malignant and senescent cells. Moreover, SASPs extracellularly manifest to induce paracrine senescence. Macrophage senescence escalates to organ level malfunction, and the organism is more prone to ARDs. By targeting genes and proteins or functioning as competing endogenous RNA (ceRNA), lncRNA regulates different phenomena including inflammaging and ARDs. The detailed mechanism warrants further elucidation to obtain pathological evidence of ARDs and potential treatment approaches.

The regulatory roles and potential prognosis implications of long non-coding RNAs in gastric cancer

Accumulating dysregulated lncRNAs have been demonstrated to execute vital functions in the pathogenesis and progress of gastric cancer (GC) through versatile molecular mechanisms. In this review, we classify the mechanisms of dysregulated lncRNAs in GC into several governing types according to their roles at molecular level. For each regulatory role, we illustrate several instructive examples and introduce significant effects of lncRNAs on cellular biological properties of GC. Besides, we summarize a group of lncRNA-signatures that are potential biomarkers in the prediction of prognosis for GC patients.

LncRNAs Regulatory Networks in Cellular Senescence

Long noncoding RNAs (lncRNAs) are a class of transcripts longer than 200 nucleotides with no open reading frame. They play a key role in the regulation of cellular processes such as genome integrity, chromatin organization, gene expression, translation regulation, and signal transduction. Recent studies indicated that lncRNAs are not only dysregulated in different types of diseases but also function as direct effectors or mediators for many pathological symptoms. This review focuses on the current findings of the lncRNAs and their dysregulated signaling pathways in senescence. Different functional mechanisms of lncRNAs and their downstream signaling pathways are integrated to provide a bird’s-eye view of lncRNA networks in senescence. This review not only highlights the role of lncRNAs in cell fate decision but also discusses how several feedback loops are interconnected to execute persistent senescence response. Finally, the significance of lncRNAs in senescence-associated diseases and their therapeutic and diagnostic potentials are highlighted.

Peripheral expression of long non-coding RNAs in bipolar patients

BACKGROUND

Long non-coding RNAs (lncRNAs) have established roles in the pathogenesis of diverse human disorders including neuropsychiatric disorders.

METHODS

In the current study, we evaluated expression levels of six apoptosis-related lncRNAs (CCAT2, TUG1, PANDA, NEAT1, FAS-AS1 and OIP5-AS1) in the peripheral blood of bipolar disorder (BD) patients and healthy subjects to assess their contribution in the pathogenesis of BD.

RESULTS

CCAT2, TUG1 and PANDA were up-regulated in total BD patients compared with total healthy subjects (P values = 0.006, <0.001 and 0.004 respectively) while OIP5-AS1 was down-regulated (P = 0.001). When expression levels of these genes were compared between patients and sex-matched healthy subjects, CCAT2 and TUG1 expression levels were only different in male subgroups; while PANDA expression was different in both male and female subgroups compared with the corresponding control subgroups. Transcript levels of lncRNAs were not correlated with any of demographic or clinical parameters of BD patients or controls after adjustment for gender. Pairwise correlations between expression levels of lncRNAs followed a disease-dependent manner. Based on receiver operating characteristic curves, among the assessed lncRNAs TUG1 had the highest diagnostic power in BD. Combination of transcript levels of CCAT2, TUG1, PANDA and OIP5-AS1 improved both sensitivity and specificity resulting in diagnostic power of 0.96.

CONCLUSION

Our data demonstrated a possible role of certain lncRNAs in the pathogenesis of BD and potentiated them as diagnostic markers in this disorder.

Long Non-Coding RNAs as Mediators of Tumor Microenvironment and Liver Cancer Cell Communication

The tumor microenvironment is an important concept that defines cancer development not only through tumor cells themselves but also the surrounding cellular and non-cellular components, including stromal cells, blood vessels, infiltrating inflammatory cells, cancer stem cells (CSC), cytokines, and growth factors, which act in concert to promote tumor cell survival and metastasis. Hepatocellular carcinoma (HCC) is one of the most common and aggressive human malignancies worldwide. Poor prognosis is largely attributable to the high rate of tumor metastasis, highlighting the importance of identifying patients at risk in advance and developing novel therapeutic targets to facilitate effective intervention. Long non-coding RNAs (lncRNA) are a class of non-protein coding transcripts longer than 200 nucleotides frequently dysregulated in various cancer types, which have multiple functions in widespread biological processes, including proliferation, apoptosis, metastasis, and metabolism. lncRNAs are involved in regulation of the tumor microenvironment and reciprocal signaling between cancer cells. Targeting of components of the tumor microenvironment or cancer cells has become a considerable focus of therapeutic research and establishing the effects of different lncRNAs on this network should aid in the development of effective treatment strategies. The current review provides a summary of the essential properties and functional roles of known lncRNAs associated with the tumor microenvironment in HCC.

Long non-coding RNA CRNDE promotes the proliferation, migration and invasion of hepatocellular carcinoma cells through miR-217/MAPK1 axis

Hepatocellular carcinoma (HCC) is an invasive malignant tumour and the second major cause of cancer‐related deaths over the world. CRNDE and miR‐217 are non‐coding RNAs which play critical roles in cell growth, proliferation, migration. Mitogen‐activated protein kinase 1 (MAPK1) also participates in cancer cell process. Hence, this study aimed at investigating the effect of CRNDE on migration and invasion of HCC and figuring out the role of miR‐217 and MAPK1 in this process. The overexpression of CRNDE was demonstrated by a microarray‐based lncRNA profiling study. CRNDE expression in HCC was verified by qRT‐PCR. MTT assay and BrdU staining were applied to detect cell proliferation level. Transwell assay was utilized to examine cell migration and invasiveness abilities. Wound healing assay was performed for further exploration of cell migration capacity. MiR‐217 was predicted by bioinformatics. The dual luciferase reporter assay was performed to corroborate the targeting relationship between CRNDE, miR‐217 and MAPK1. MAPK1, the downstream target of miR‐217, was predicted using bioinformatics and was further confirmed by qRT‐PCR and Western blot. The interaction between CRNDE, miR‐217 and MAPK1 was studied by qRT‐PCR, Western blot, MTT, BrdU, transwell assay and wound healing assay. CRNDE was up‐regulated in HCC tissues and HCC cell lines. The high expression of CRNDE facilitated cell proliferation, migration and invasion, while the inhibited one affected on the contrary. MiR‐217, negatively correlated with CRNDE expression, was the target of CRNDE and was more lowly expressed in HCC. With the high expression of miR‐217, HCC cell proliferation, migration and invasion were suppressed. MAPK1, the possible target of miR‐217, was negatively correlated with miR‐217 but positively correlated with CRNDE and had the same effect in HCC formation process as CRNDE. Long non‐coding RNA CRNDE promotes the proliferation, migration and invasion of HCC cells through miR‐217/MAPK1 axis.

Exploring the mechanisms behind long noncoding RNAs and cancer

Over the past decade, long noncoding RNAs (lncRNAs) have been identified as significant players in gene regulation. They are often differentially expressed and widely-associated with a majority of cancer types. The aberrant expression of these transcripts has been linked to tumorigenesis, metastasis, cancer stage progression and patient survival. Despite their apparent link to cancer, it has been challenging to gain a mechanistic understanding of how they contribute to cancer, partially due the difficulty in discriminating functional RNAs from other noncoding transcription events. However, there are several well-studied lncRNAs where specific mechanisms have been more clearly defined, leading to new discoveries into how these RNAs function. One major observation that has come to light is the context-dependence of lncRNA mechanisms, where they often have unique function in specific cell types and environment. Here, we review the molecular mechanisms of lncRNAs with a focus on cancer pathways, illustrating a few informative examples. Together, this type of detailed insight will lead to a greater understanding of the potential for the application of lncRNAs as targets of cancer therapies and diagnostics.

Cellular senescence and liver disease: Mechanisms and therapeutic strategies

Cellular senescence is a fundamental cell fate caused by several cellular injuries which results in irreversible cell cycle arrest yet remaining metabolically active across all species. Cellular senescence not only can prevent tumor occurrence by inhibiting the proliferation of injured cells, but also can affect the surrounding cells through the senescence-associated secretory phenotype (SASP). Attractively, accumulating evidence shows that cellular senescence is closely related to various liver diseases. Therapeutic opportunities based on targeting senescent cells and the SASP are considered to be potential strategy for liver diseases. However, although research on cell senescence has attracted widespread attention, the overview on detailed mechanism and biological function of cell senescence in liver disease is still largely unknown. The present review summarizes the specific role of cell senescence in various liver diseases, and updates the molecular mechanisms underlying cell senescence. Moreover, the review also explores new strategies for prevention and treatment of liver disease through promoting senescence or counteracting excessive pathological senescence.