The Interplay of LncRNA-H19 and Its Binding Partners in Physiological Process and Gastric Carcinogenesis. Int J Mol Sci. 2017;18:pii: E450. [PMID: 28230721 PMCID: PMC5343984 DOI: 10.3390/ijms18020450]

Long noncoding RNAs in ubiquitination, protein degradation, and human diseases

Protein stability and turnover is critical in normal cellular and physiological process and their misregulation may contribute to accumulation of unwanted proteins causing cellular malfunction, neurodegeneration, mitochondrial malfunction, and disrupted metabolism. Signaling mechanism associated with protein degradation is complex and is extensively studied. Many protein and enzyme machineries have been implicated in regulation of protein degradation. Despite these insights, our understanding of protein degradation mechanisms remains limited. Emerging studies suggest that long non-coding RNAs (lncRNAs) play critical roles in various cellular and physiological processes including metabolism, cellular homeostasis, and protein turnover. LncRNAs, being large nucleic acids (>200 nt long) can interact with various proteins and other nucleic acids and modulate protein structure and function leading to regulation of cell signaling processes. LncRNAs are widely distributed across cell types and may exhibit tissue specific expression. They are detected in body fluids including blood and urine. Their expressions are also altered in various human diseases including cancer, neurological disorders, immune disorder, and others. LncRNAs are being recognized as novel biomarkers and therapeutic targets. This review article focuses on the emerging role of noncoding RNAs (ncRNAs), particularly long noncoding RNAs (lncRNAs), in the regulation of protein polyubiquitination and proteasomal degradation.

Research progress on long non‑coding RNAs in non‑infectious spinal diseases (Review)

Spinal diseases, including intervertebral disc degeneration (IDD), ankylosing spondylitis, spinal cord injury and other non‑infectious spinal diseases, severely affect the quality of life of patients. Current treatments for IDD and other spinal diseases can only relieve symptoms and do not completely cure the disease. Therefore, there is an urgent need to explore the causes of these diseases and develop new treatment approaches. Long non‑coding RNA (lncRNA), a form of non‑coding RNA, is abundant in diverse sources, has numerous functions, and plays an important role in the occurrence and development of spinal diseases such as IDD. However, the mechanism of action of lncRNAs has not been fully elucidated, and significant challenges remain in the use of lncRNAs as new therapeutic targets. The present article reviews the sources, classification and functions of lncRNAs, and introduces the role of lncRNAs in spinal diseases, such as IDD, and their therapeutic potential.

A prominent role of LncRNA H19 in H. pylori CagA induced DNA damage response and cell malignancy

Helicobacter pylori (H. pylori), together with its CagA, has been implicated in causing DNA damage, cell cycle arrest, apoptosis, and the development of gastric cancer. Although lncRNA H19 is abundantly expressed in gastric cancer and functions as a pro-oncogene, it remains unclear whether lncRNA H19 contributes to the oncogenic process of H. pylori CagA. This study investigates the role of H19 in the DNA damage response and malignancy induced by H. pylori. It was observed that cells infected with CagA+ H. pylori strain (GZ7/cagA) showed significantly higher H19 expression, resulting in increased γH2A.X and p-ATM expression and decreased p53 and Rad51 expression. Faster cell migration and invasion was also observed, which was reversed by H19 knockdown in H. pylori. YWHAZ was identified as an H19 target protein, and its expression was increased in H19 knockdown cells. GZ7/cagA infection responded to the increased YWHAZ expression induced by H19 knockdown. In addition, H19 knockdown stimulated cells to enter the G2-phase and attenuated the effect of GZ7/cagA infection on the cellular S-phase barrier. The results suggest that H. pylori CagA can upregulate H19 expression, participate in the DNA damage response and promote cell migration and invasion, and possibly affect cell cycle arrest via regulation of YWHAZ.

Emerging roles of long noncoding RNA H19 in human lung cancer

Lung cancer holds the position of being the primary cause of cancer-related fatalities on a global scale. Furthermore, it exhibits the highest mortality rate among all types of cancer. The survival rate within a span of 5 years is less than 20%, primarily due to the fact that the disease is often diagnosed at an advanced stage, resulting in less effective treatment options compared to earlier stages. There are two main types of primary lung cancer: nonsmall-cell lung cancer, which accounts for approximately 80%-85% of all cases, and small-cell lung cancer, which is categorized based on the specific type of cells in which the cancer originates. The understanding of the biology of this disease and the identification of oncogenic driver alterations have significantly transformed the landscape of therapeutic approaches. Long noncoding RNAs (lncRNAs) play a crucial role in regulating various physiological and pathological processes through diverse molecular mechanisms. Among these lncRNAs, lncRNA H19, initially identified as an oncofetal transcript, has garnered significant attention due to its elevated expression in numerous tumors. Extensive research has confirmed its involvement in tumorigenesis and malignant progression by promoting cell growth, invasion, migration, epithelial-mesenchymal transition, metastasis, and therapy resistance. This comprehensive review aims to provide an overview of the aberrant overexpression of lncRNA H19 and the molecular pathways through which it contributes to the advancement of lung cancer. The findings of this review highlight the potential for further investigation into the diagnosis and treatment of this disease, offering promising avenues for future research.

METTL3-mediated deficiency of lncRNA HAR1A drives non-small cell lung cancer growth and metastasis by promoting ANXA2 stabilization

We previously reported lncRNA HAR1A as a tumor suppressor in non-small cell lung cancer (NSCLC). However, the delicate working mechanisms of this lncRNA remain obscure. Herein, we demonstrated that the ectopic expression of HAR1A inhibited the proliferation, epithelial-mesenchymal transition (EMT), migration, and invasion of NSCLC cells and enhanced paclitaxel (PTX) sensitivity in vitro and in vivo. We identified the oncogenic protein annexin 2 (ANXA2) as a potential interacting patterner of HAR1A. HAR1A overexpression enhanced ANXA2 ubiquitination and accelerated its degradation via the ubiquitin-proteasome pathway. We further uncovered that HAR1A promoted the interaction between E3 ubiquitin ligase TRIM65 and ANXA2. Moreover, the ANXA2 plasmid transfection could reverse HAR1A overexpression-induced decreases in proliferation, migration, and invasion of NSCLC cells and the activity of the NF-κB signaling pathway. Finally, we found that HAR1A loss in NSCLC might be attributed to the upregulated METTL3. The m6A modification levels of HAR1A were increased in cancer cells, while YTHDF2 was responsible for recognizing m6A modification in the HAR1A, leading to the disintegration of this lncRNA. In conclusion, we found that METTL3-mediated m6A modification decreased HAR1A in NSCLC. HAR1A deficiency, in turn, stimulated tumor growth and metastasis by activating the ANXA2/p65 axis.

Research Progress of Long Non-Coding RNA in Tumor Drug Resistance: A New Paradigm

In the past few decades, chemotherapy has been one of the most effective cancer treatment options. Drug resistance is currently one of the greatest obstacles to effective cancer treatment. Even though drug resistance mechanisms have been extensively investigated, they have not been fully elucidated. Recent genome-wide investigations have revealed the existence of a substantial quantity of long non-coding RNAs (lncRNAs) transcribed from the human genome, which actively participate in numerous biological processes, such as transcription, splicing, epigenetics, the cell cycle, cell differentiation, development, pluripotency, immune microenvironment. The abnormal expression of lncRNA is considered a contributing factor to the drug resistance. Furthermore, drug resistance may be influenced by genetic and epigenetic variations, as well as individual differences in patient treatment response, attributable to polymorphisms in metabolic enzyme genes. This review focuses on the mechanism of lncRNAs resistance to target drugs in the study of tumors with high mortality, aiming to establish a theoretical foundation for targeted therapy.

The emerging roles of long non-coding RNA (lncRNA) H19 in gynecologic cancers

Long non-coding RNA (lncRNA) H19 has gained significant recognition as a pivotal contributor to the initiation and advancement of gynecologic cancers, encompassing ovarian, endometrial, cervical, and breast cancers. H19 exhibits a complex array of mechanisms, demonstrating dualistic effects on tumorigenesis as it can function as both an oncogene and a tumor suppressor, contingent upon the specific context and type of cancer being investigated. In ovarian cancer, H19 promotes tumor growth, metastasis, and chemoresistance through modulation of key signaling pathways and interaction with microRNAs. Conversely, in endometrial cancer, H19 acts as a tumor suppressor by inhibiting proliferation, inducing apoptosis, and regulating epithelial-mesenchymal transition. Additionally, H19 has been implicated in cervical and breast cancers, where it influences cell proliferation, invasion, and immune evasion. Moreover, H19 has potential as a diagnostic and prognostic biomarker for gynecologic cancers, with its expression levels correlating with clinical parameters and patient outcomes. Understanding the functional roles of H19 in gynecologic cancers is crucial for the development of targeted therapeutic strategies and personalized treatment approaches. Further investigation into the intricate molecular mechanisms underlying H19's involvement in gynecologic malignancies is warranted to fully unravel its therapeutic potential and clinical implications. This review aims to elucidate the functional roles of H19 in various gynecologic malignancies.

Non-coding RNAs' function in cancer development, diagnosis and therapy

While previous research on cancer biology has focused on genes that code for proteins, in recent years it has been discovered that non-coding RNAs (ncRNAs)play key regulatory roles in cell biological functions. NcRNAs account for more than 95% of human transcripts and are an important entry point for the study of the mechanism of cancer development. An increasing number of studies have demonstrated that ncRNAs can act as tumor suppressor genes or oncogenes to regulate tumor development at the epigenetic level, transcriptional level, as well as post-transcriptional level. Because of the importance of ncRNAs in cancer, most clinical trials have focused on ncRNAs to explore whether ncRNAs can be used as new biomarkers or therapies. In this review, we focus on recent studies of ncRNAs including microRNAs (miRNAs), long ncRNAs (lncRNAs), circle RNAs (circRNAs), PIWI interacting RNAs (piRNAs), and tRNA in different types of cancer and explore the application of these ncRNAs in the development of cancer and the identification of relevant therapeutic targets and tumor biomarkers. Graphical abstract drawn by Fidraw.

Impact of rs2107425 Polymorphism and Expression of lncH19 and miR-200a on the Susceptibility of Colorectal Cancer

Cancer is the most common leading cause of mortality, making it a critical public health issue worldwide. Environmental and genetic abnormalities play a role in carcinogenesis, characterized by single nucleotide polymorphisms (SNPs) and abnormal gene expression. Also, non-coding RNA is a hot spot in cancer growth and metastasis. This study aimed to demonstrate the contribution of LncRNA H-19 rs2107425 to colorectal cancer (CRC) susceptibility and the correlation between miR-200a and LncRNA H-19 in patients with CRC. The current study was conducted on 100 participants, divided into 70 subjects with colorectal cancer and 30 age- and sex-matched healthy subjects. Patients with CRC experienced a significant elevation in WBC count, platelets, ALT, AST, and CEA. However, hemoglobin and albumin notably declined in patients with CRC compared with those in healthy controls. The expression of LncRNA H-19 and miR-200a increased in patients with CRC with a significant difference compared to healthy controls. Moreover, LncRNA H-19 and miR-200a expression significantly increased in stage III CRC compared to stage II CRC. As compared to carriers with the homozygous CC genotype, the frequency of rs2107425 CT and rs2107425 TT increased in patients with CRC. Our results indicate that the rs2107425 SNP of LncRNA H-19 may serve as a novel susceptibility marker for colorectal cancer. Moreover, miR-200a and LncRNA H-19 are prospective biomarkers of colorectal cancer.

Long noncoding RNA (lncRNA) H19: An essential developmental regulator with expanding roles in cancer, stem cell differentiation, and metabolic diseases

Recent advances in deep sequencing technologies have revealed that, while less than 2% of the human genome is transcribed into mRNA for protein synthesis, over 80% of the genome is transcribed, leading to the production of large amounts of noncoding RNAs (ncRNAs). It has been shown that ncRNAs, especially long non-coding RNAs (lncRNAs), may play crucial regulatory roles in gene expression. As one of the first isolated and reported lncRNAs, H19 has gained much attention due to its essential roles in regulating many physiological and/or pathological processes including embryogenesis, development, tumorigenesis, osteogenesis, and metabolism. Mechanistically, H19 mediates diverse regulatory functions by serving as competing endogenous RNAs (CeRNAs), Igf2/H19 imprinted tandem gene, modular scaffold, cooperating with H19 antisense, and acting directly with other mRNAs or lncRNAs. Here, we summarized the current understanding of H19 in embryogenesis and development, cancer development and progression, mesenchymal stem cell lineage-specific differentiation, and metabolic diseases. We discussed the potential regulatory mechanisms underlying H19's functions in those processes although more in-depth studies are warranted to delineate the exact molecular, cellular, epigenetic, and genomic regulatory mechanisms underlying the physiological and pathological roles of H19. Ultimately, these lines of investigation may lead to the development of novel therapeutics for human diseases by exploiting H19 functions.

LncRNA LINC01094 Promotes Cells Proliferation and Metastasis through the PTEN/AKT Pathway by Targeting AZGP1 in Gastric Cancer

Long noncoding RNAs (lncRNAs) were recently reported to play an essential role in multiple cancer types. Herein, through next-generation sequencing, we screened metastasis-driving molecules by using tissues from early-stage gastric cancer (GC) patients with lymph node metastasis, and we identified a lncRNA LINC01094, which was associated with the metastasis of GC. According to the clinical data from the TCGA, GSE15459, and GSE62254 cohorts, the high expression of LINC01094 was associated with an unfavorable prognosis. Moreover, 106 clinical GC and paired normal samples were collected, and the qRT-PCR results showed that the high expression of LINC01094 was associated with high T and N stages and a poor prognosis. We found that LINC01094 promotes the proliferation and metastasis of GC in vitro and in vivo. AZGP1 was found as the protein-binding partner of LINC01094 by using RNA pulldown and RNA-binding protein immunoprecipitation (RIP) assays. LINC01094 antagonizes the function of AZGP1, downregulates the expression of PTEN, and further upregulates the AKT pathway. Collectively, our results suggested that LINC01094 might predict the prognosis of GC patients and become the therapy target for GC.

The function of natural compounds in important anticancer mechanisms

The existence of malignant tumors has been a threat to human life, health, and safety. Although the rapid development of radiotherapy, drug therapy, surgery, and local therapy has improved the quality of life of tumor patients, there are still some risks. Natural compounds are widely used in cancer because they are easy to obtain, have a good curative effects and have no obvious side effects, and play a vital role in the prevention and treatment of various cancers. Phenolic, flavonoids, terpenoids, alkaloids, and other natural components of traditional Chinese medicine have certain anti-tumor activities, which can promote apoptosis, anti-proliferation, anti-metastasis, inhibit angiogenesis, change the morphology of cancer cells and regulate immune function, etc., and have positive effects on breast cancer, liver cancer, lung cancer, gastric cancer, rectal cancer and so on. To better understand the effects of natural compounds on cancer, this paper screened out four important pathways closely related to cancer, including cell death and immunogenic cell death, immune cells in the tumor microenvironment, inflammation and related pathways and tumor metastasis, and systematically elaborated the effects of natural compounds on cancer.

The Potential Utility of Circulating Oncofetal H19 Derived miR-675 Expression versus Tissue lncRNA-H19 Expression in Diagnosis and Prognosis of HCC in Egyptian Patients

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Interestingly, lncRNA-H19 acts independently in HCC and influences miR-675 expressions. We aimed to assess the potential utility of tissue lncRNA-H19 versus miR-675 expressions as a non-invasive biomarker for HCC diagnosis and prognosis in Egyptian patients. Ninety-one HCC patients and 91 controls included in this study were investigated for expression of lncRNA-H19 and miR675 using RT-qPCR. Our results showed that the expression of lncRNA-H19 and microRNA-675 were higher in patients than in controls (p < 0.001 for both). Additionally, lncRNA-H19 expression was higher in tumorous than in non-tumorous tissue (p < 0.001). Linear regression revealed that miR-675 expression was a significantly higher positive predictor than lncRNA-H19 for tumor size, pathologic grade, and AFP level; similarly, for cyclin D1 and VEGF protein expression. By using the ROC curve, the sensitivity of miR-675 was higher than lncRNA-H19 for discriminating HCC from controls (95-89%, respectively) and the sensitivity of lncRNA-H19 was higher in tumorous than in non-tumorous tissues (76%). The high expressions of both were associated with low OS (p < 0.001, 0.001, respectively). Oncofetal H19-derived miR-675 expression could be considered a potential noninvasive diagnostic and prognostic biomarker, outstanding the performance of the expression of tissue lncRNA-H19 for HCC.

The role of lncRNA H19 in tumorigenesis and drug resistance of human Cancers

Systemic therapy is one of the most significant cancer treatments. However, drug resistance often appears and has become the primary cause of cancer therapy failure. Regulation of drug target, drug metabolism and drug efflux, cell death escape (apoptosis, autophagy, et al.), epigenetic changes, and many other variables are complicatedly involved in the mechanisms of drug resistance. In various types of cancers, long non-coding RNA H19 (lncRNA H19) has been shown to play critical roles in tumor development, proliferation, metastasis, and multiple drug resistance as well. The efficacy of chemotherapy, endocrine therapy, and targeted therapy are all influenced by the expression of H19, especially in breast cancer, liver cancer, lung cancer and colorectal cancer. Here, we summarize the relationship between lncRNA H19 and tumorigenesis, and illustrate the drug resistance mechanisms caused by lncRNA H19 as well. This review may provide more therapeutic potential targets for future cancer treatments.

LncRNA H19 Promotes Lung Adenocarcinoma Progression via Binding to Mutant p53 R175H

Simple Summary

This research explored the association and interaction between lncRNA H19 and mutant p53 (R175H) in lung adenocarcinoma development and progression. H19 over-expression may induce the elevated expression of mtp53 and interact with mtp53, which prolongs the p53 half-life and promotes transcriptional activity, leading to the progression of lung adenocarcinoma. The simultaneous inhibition of H19 and mtp53 may provide a novel strategy.

Abstract

Background: Accumulating data suggest that long non-coding RNA (lncRNA) H19 and p53are closely related to the prognosis of lung cancer. This study aims to analyze the association and interaction betweenH19 and mutant p53 R175H in lung adenocarcinoma (LAC). Methods: Mutant-type (Mt) p53 R175H was assessed by using RT-PCR in LAC cells and 100 cases of LAC tissue samples for association with H19 expression. Western blot, RNA-pull down, immunoprecipitation-Western blot and animal experiments were used to evaluate the interaction between H19 and mtp53. Results: Mtp53 R175H and H19 were over-expressed in LAC tissues and cells, while H19 over-expression extended the p53 half-life and enhanced transcriptional activity. Combined with anti-p53, ShH19 can significantly inhibit tumor growth in vivo. Conclusions: H19 over-expression may induce the elevated expression of mtp53 and interact with mtp53, leading to LAC progression. In addition, the high expression of mtp53 R175H is associated with poor overall survival inpatients. The simultaneous inhibition of H19 and mtp53 may provide a novel strategy for the effective control of LAC clinically.

The Antigastric Cancer Effect of Triptolide is Associated With H19/NF-κB/FLIP Axis

Background and Objective: Triptolide (TP), one of the fat-soluble components extracted from the Chinese medicinal herb Tripterygium wilfordii Hook F. (TWHF), possesses strong antitumor bioactivities, but its dose-dependent side effects restrict its wide application. This study was designed to investigate whether inflammatory factors increased the antitumor effects of the nontoxic dose of TP on gastric cancer cells and tried to explore the possible molecular mechanisms.

Method: AGS and MKN45 cells were treated with different doses of TP and TNF-α. Cell viability and apoptosis were detected in vitro. In addition, NF-κB mediated prosurvival signals and cytoprotective proteins, especially FLICE-inhibitory protein (FLIP), were detected to determine their effects on TP/TNF-α–induced apoptosis. Moreover, the function of lncRNA H19/miR-204-5p/NF-κB/FLIP axis was investigated in vitro, and the antigastric cancer effect of TP plus TNF-α was proved in the mice xenograft model.

Result:In vitro experimental results showed that TP pretreatment promoted apoptosis in AGS and MKN45 cells upon TNF-α exposure. TP/TNF-α–mediated apoptosis was partly mediated by the inhibitory effect of NF-κB–mediated FLIP expression. Oncogene H19 lying in the upstream pathway of NF-κB played a vital role upon TNF-α exposure, and bioinformatics analysis proved that H19 participated in TP/TNF-α–induced apoptosis via binding of miR-204-5p. Lastly, a low dose of TP and TNF-α inhibited the tumor weight and tumor volume of AGS and MKN45 cells in vivo.

Conclusion: TP pretreatment increased apoptosis in TNF-α–stimulated gastric cancer cells, which are dependent on the disruption of the H19/miR-204-5p/NF-κB/FLIP axis. Cotreatment of TP and TNF-α is a better option for enhancing the anticancer effect and lowering the side effect of TP.

Non-coding RNAs and macrophage interaction in tumor progression

The macrophages are abundantly found in TME and their M2 polarization is in favor of tumor malignancy. On the other hand, non-coding RNAs (ncRNAs) can modulate macrophage polarization in TME to affect cancer progression. The miRNAs can dually induce/suppress M2 polarization of macrophages and by affecting various molecular pathways, they modulate tumor progression and therapy response. The lncRNAs can affect miRNAs via sponging and other molecular pathways to modulate macrophage polarization. A few experiments have also examined role of circRNAs in targeting signaling networks and affecting macrophages. The therapeutic targeting of these ncRNAs can mediate TME remodeling and affect macrophage polarization. Furthermore, exosomal ncRNAs derived from tumor cells or macrophages can modulate polarization and TME remodeling. Suppressing biogenesis and secretion of exosomes can inhibit ncRNA-mediated M2 polarization of macrophages and prevent tumor progression. The ncRNAs, especially exosomal ncRNAs can be considered as non-invasive biomarkers for tumor diagnosis.

Recent Advances of LncRNA H19 in Diabetes LncRNA H19 in Diabetes

Diabetes mellitus (DM) causes damage to major organs, including the heart, liver, brain, kidneys, eyes, and blood vessels, threatening the health of the individuals. Emerging evidence has demonstrated that lncRNAs has important functions in the pathogenesis of human diseases, such as cancers, neurodegenerative diseases, cardiac fibroblast phenotypes, hypertension, heart failure, atherosclerosis and diabetes. Recently, H19, a lncRNA, has been reported to shown to participate in the regulatory process of muscle differentiation, glucose metabolism, and tumor metastasis, as well as endometrial development. However, the roles of H19 in DM were still not completely understood. This review was conducted to summarize the functions of H19 in diabetes and discuss the challenges and possible strategies of H19 in DM.

Modulation of lncRNA H19 enhances resveratrol-inhibited cancer cell proliferation and migration by regulating endoplasmic reticulum stress

The phytoalexin resveratrol exhibits anti-tumour activity in many types of cancer. In this study, we showed that resveratrol suppressed the survival of gastric tumour cells both in vivo and in vitro. Resveratrol promoted apoptosis, autophagy and endoplasmic reticulum (ER) stress in a dose-dependent manner. RNA-seq analysis showed that multiple cell death signalling pathways were activated after resveratrol treatment, while the use of ER stress activators (tunicamycin and thapsigargin) in combinatorial with resveratrol led to further inhibition of cancer cell survival. Results also showed that resveratrol altered the expression of several long non-coding RNAs (lncRNAs), including MEG3, PTTG3P, GAS5, BISPR, MALAT1 and H19. Knockdown of H19 in resveratrol-treated cells further enhanced the effects of resveratrol on apoptosis, ER stress and cell cycle S-phase arrest. Furthermore, the migratory ability of resveratrol-treated cells was dramatically decreased after H19 knockdown. In conclusion, resveratrol inhibited cancer cell survival, while knockdown of lncRNA H19 resulted in increased sensitivity to resveratrol therapy.

Long Noncoding RNA H19: A Novel Therapeutic Target Emerging in Oncology Via Regulating Oncogenic Signaling Pathways

Long noncoding RNA H19 (H19) is an imprinting gene with only maternal expression that is involved in regulating different processes in various types of cells. Previous studies have shown that abnormal H19 expression is involved in many pathological processes, such as cancer, mainly through sponging miRNAs, interacting with proteins, or regulating epigenetic modifications. Accumulating evidence has shown that several oncogenic signaling pathways lead to carcinogenesis. Recently, the regulatory relationship between H19 and oncogenic signaling pathways in various types of cancer has been of great interest to many researchers. In this review, we discussed the key roles of H19 in cancer development and progression via its regulatory function in several oncogenic signaling pathways, such as PI3K/Akt, canonical Wnt/β-catenin, canonical NF-κB, MAPK, JAK/STAT and apoptosis. These oncogenic signaling pathways regulated by H19 are involved in cell proliferation, proliferation, migration and invasion, angiogenesis, and apoptosis of various cancer cells. This review suggests that H19 may be a novel therapeutic target for cancers treatment by regulating oncogenic signaling pathways.

Peripheral Blood-Based DNA Methylation of Long Non-Coding RNA H19 and Metastasis-Associated Lung Adenocarcinoma Transcript 1 Promoters are Potential Non-Invasive Biomarkers for Gastric Cancer Detection

Introduction

The early diagnosis and detection could greatly improve the clinical outcome of gastric cancer (GC) patients. However, the non-invasive biomarkers for GC detection remain to be identified.

Method

We used online databases (GEPIA, UALCAN, Kaplan-Meier plotter, TIMER, and MEXPRESS) to explore the association between H19 or metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) expression in tissues and the occurrence, development, prognosis, the levels of immune cell infiltration, and methylation of GC; the correlation between mRNA expression and DNA methylation levels of genes were also examined. Methylation levels of H19 or MALAT1 in peripheral blood were compared between 150 GC patients and 100 healthy controls (HCs). Predictive nomograms were constructed among female and male groups for GC diagnosis. The calibration curves, Hosmer–Lemeshow test, and decision curve analysis were also used to examine the nomograms’ predictive ability and clinical values.

Results

Using multiple online databases, we found that the mRNA expressions of H19 and MALAT1 in tissues were related to the occurrence of GC, and such expressions were associated with immune cell infiltration of GC and negatively correlated with DNA methylation levels of H19 and MALAT1. H19 gene, H19C island, and MALAT1B island, as well as 20 CpG sites were hypermethylated in peripheral blood of GC patients compared with HCs; similar results were also found in female and male groups (P < .05 for all). The combination of H19c3, H19c4, MALAT1b12, and age, as well as the combination of H19b7, H19c1, H19c5, and age in the nomograms could distinguish GC patients from HCs in the female group and male group, respectively.

Conclusion

We found statistically significant hypermethylation of H19 and MALAT1 promoters in GC patients, and meaningful sensitivity and specificity of MALAT1 and H19 methylation in discriminating GC and HCs were observed in both female and male groups, which indicates that the peripheral blood-based DNA methylation of H19 and MALAT1 could act as potential non-invasive biomarkers for the diagnosis of GC.

Cardiac pathologies in mouse loss of imprinting models are due to misexpression of H19 long noncoding RNA

Maternal loss of imprinting (LOI) at the H19/IGF2 locus results in biallelic IGF2 and reduced H19 expression and is associated with Beckwith--Wiedemann syndrome (BWS). We use mouse models for LOI to understand the relative importance of Igf2 and H19 mis-expression in BWS phenotypes. Here we focus on cardiovascular phenotypes and show that neonatal cardiomegaly is exclusively dependent on increased Igf2. Circulating IGF2 binds cardiomyocyte receptors to hyperactivate mTOR signaling, resulting in cellular hyperplasia and hypertrophy. These Igf2-dependent phenotypes are transient: cardiac size returns to normal once Igf2 expression is suppressed postnatally. However, reduced H19 expression is sufficient to cause progressive heart pathologies including fibrosis and reduced ventricular function. In the heart, H19 expression is primarily in endothelial cells (ECs) and regulates EC differentiation both in vivo and in vitro. Finally, we establish novel mouse models to show that cardiac phenotypes depend on H19 lncRNA interactions with Mirlet7 microRNAs.

The Role of LncRNA H19 in MAPK Signaling Pathway Implicated in the Progression of Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD), also known as neonatal chronic lung disease, is an important cause of respiratory illness in preterm newborns that results in significant morbidity and mortality. Long noncoding RNAs (lncRNAs) have been discovered with many biological functions. However, the role of lncRNAs in the pathogenesis of BPD remains poorly understood. Here, we established a mouse lung injury model that mimicked human BPD. Subsequently, we found the lncRNA H19 expression level was significantly increased in BPD compared with normal lung tissues using quantitative real-time polymerase chain reaction. Next, we observed that overexpression of lncRNA H19 enhanced mitogen-activated protein kinase (MAPK) signaling pathway. In addition, we also found that dysfunction of lncRNA H19 altered the expression of inflammatory factors. Thus, our study validates that lncRNA H19 contributes to the progression of BPD by regulating MAPK signaling pathway, which could be used as a potential target for treating BPD.

Long non-coding RNAs regulating multiple proliferative pathways in cancer cell

Long non-coding RNAs (lncRNAs) belong to an extremely heterogeneous class of non-coding RNAs with a length ranging from 200 to 100,000 bp. They modulate a series of cellular pathways in both physiological and pathological context. It is no coincidence that they are expressed in an aberrant way in pathologies such as cancer, so as to deserve to be subclassified as oncogenes or tumor suppressors. These molecules are also involved in the regulation of cancer cell proliferation. Several lncRNAs are able to modulate cell growth both positively and negatively, and in this review we have focused on a small group of them, characterized by the simultaneous action on different pathways regulating cell proliferation. They have been considered in the light of their behavior in three different subtypes of proliferative pathways that we can define as (I) tumor suppressor, (II) oncogenic and (III) transcriptionally-driven. More specifically, we have characterized some lncRNAs considered oncogenes (such as H19, linc-ROR, MALAT1, HULC, HOTAIR and ANRIL), tumor suppressors (such as MEG3 and lincRNA-p21), and both oncogenes/tumor suppressors (UCA1 and TUG1) in a little more detail. As can be understood from the review, the interactions between lncRNAs and their molecular targets, only in the context of controlling cell proliferation, give rise to an intricate molecular network, the understanding of which, in the future, will certainly be of help for the treatment of molecular diseases such as cancer.

Circulating exosomal long non-coding RNA H19 as a potential novel diagnostic and prognostic biomarker for gastric cancer

Objective

Long non-coding RNAs (lncRNAs) are involved in carcinogenesis and could be used as diagnostic biomarkers. Our study aimed to elucidate the clinical role of serum exosomal lncRNA H19 in gastric cancer (GC).

Methods

In this prospective clinical study, we determined serum exosomal lncRNA H19 levels in 81 patients with GC and analysed the correlations between serum lncRNA H19 levels and clinical characteristics. Receiver operating characteristics (ROC) curves were constructed to determine the diagnostic performance of exosomal lncRNA H19 in GC.

Results

Serum exosomal lncRNA H19 levels were significantly upregulated in patients with GC both before and after surgery compared with healthy controls. Furthermore, serum exosomal lncRNA H19 levels were significantly decreased after compared with before surgery in patients with GC. Preoperative lncRNA H19 levels were significantly correlated with TNM stage. The area under the ROC curve (AUC) value for exosomal lncRNA H19 was 0.849, which was significantly higher than the AUC values for cancer antigens 19-9 and 72-4 and carcinoembryonic antigen, either alone or combined.

Conclusions

These results suggest that circulating exosomal lncRNA H19 may be a potential biomarker with diagnostic and prognostic value in GC.

Long Non-coding RNA: A Key Regulator in the Pathogenesis of Diabetic Cardiomyopathy

In recent years, diabetes mellitus has become a global issue with increasing incidence rate worldwide. Diabetic cardiomyopathy (DCM), one of the important complications of diabetes, refers to patients with type 1 and type 2 diabetes who have ventricular hypertrophy, fibrosis and even diastolic dysfunction. The pathogenesis of DCM is related to oxidative stress, inflammatory response, apoptosis, autophagy, myocardial fibrosis and, diabetic microangiopathy. Long non-coding RNAs (lncRNA) is a non-coding RNA with a length longer than 200 nucleotides which lack the ability of protein coding. With the development of molecular technology, massive evidence demonstrates that lncRNA play a critical role in the molecular mechanism of DCM. Moreover, it can also be used as potential diagnostic markers for DCM. In this review, we intend to summarize the pathological roles and molecular mechanism of lncRNA in the progression of diabetic cardiomyopathy, which may provide promising diagnosis and treatment strategies for DCM.

Long noncoding RNA H19 - a new player in the pathogenesis of liver diseases

The liver is a vital organ that controls glucose and lipid metabolism, hormone regulation, and bile secretion. Liver injury can occur from various insults such as viruses, metabolic diseases, and alcohol, which lead to acute and chronic liver diseases. Recent studies have demonstrated the implications of long noncoding RNAs (lncRNAs) in the pathogenesis of liver diseases. These newly discovered lncRNAs have various functions attributing to many cellular biological processes via distinct and diverse mechanisms. LncRNA H19, one of the first lncRNAs being identified, is highly expressed in fetal liver but not in adult normal liver. Its expression, however, is increased in liver diseases with various etiologies. In this review, we focused on the roles of H19 in the pathogenesis of liver diseases. This comprehensive review is aimed to provide useful perspectives and translational applications of H19 as a potential therapeutic target of liver diseases.

IGF2BP1, a Conserved Regulator of RNA Turnover in Cancer

The oncofetal IGF2 mRNA-binding protein 1 (IGF2BP1) promotes tumor progression in a variety of solid tumors and its expression is associated with adverse prognosis. The main role proposed for IGF2BP1 in cancer cells is the stabilization of mRNAs encoding pro-oncogenic factors. Several IGF2BP1-RNA association studies, however, revealed a plethora of putative IGF2BP1-RNA targets. Thus, at present the main conserved target RNAs and pathways controlled by IGF2BP1 in cancer remain elusive. In this study, we present a set of genes and cancer hallmark pathways showing a conserved pattern of deregulation in dependence of IGF2BP1 expression in cancer cell lines. By the integrative analysis of these findings with publicly available cancer transcriptome and IGF2BP1-RNA association data, we compiled a set of prime candidate target mRNAs. These analyses confirm a pivotal role of IGF2BP1 in controlling cancer cell cycle progression and reveal novel cancer hallmark pathways influenced by IGF2BP1. For three novel target mRNAs identified by these studies, namely AURKA, HDLBP and YWHAZ, we confirm IGF2BP1 mRNA stabilization. In sum our findings confirm and expand previous findings on the pivotal role of IGF2BP1 in promoting oncogenic gene expression by stabilizing target mRNAs in a mainly 3'UTR, m⁶A-, miRNA-, and potentially AU-rich element dependent manner.

Novel Insights Linking lncRNAs and Metabolism With Implications for Cardiac Regeneration

Heart disease is the leading cause of mortality in developed countries. The associated pathology is typically characterized by the loss of cardiomyocytes that leads, eventually, to heart failure. Although conventional treatments exist, novel regenerative procedures are warranted for improving cardiac regeneration and patients well fare. Whereas following injury the capacity for regeneration of adult mammalian heart is limited, the neonatal heart is capable of substantial regeneration but this capacity is lost at postnatal stages. Interestingly, this is accompanied by a shift in the metabolic pathways and energetic fuels preferentially used by cardiomyocytes from embryonic glucose-driven anaerobic glycolysis to adult oxidation of substrates in the mitochondria. Apart from energetic sources, metabolites are emerging as key regulators of gene expression and epigenetic programs which could impact cardiac regeneration. Long non-coding RNAs (lncRNAs) are known master regulators of cellular and organismal carbohydrate and lipid metabolism and play multifaceted functions in the cardiovascular system. Still, our understanding of the metabolic determinants and pathways that can promote cardiac regeneration in the injured hearth remains limited. Here, we will discuss the emerging concepts that provide evidence for a molecular interplay between lncRNAs and metabolic signaling in cardiovascular function and whether exploiting this axis could provide ground for improved regenerative strategies in the heart.

The Signalling Effects of Photobiomodulation on Osteoblast Proliferation, Maturation and Differentiation: A Review

Proliferation of osteoblasts is essential for maturation and mineralization of bone matrix. Ossification, the natural phase of bone-forming and hardening is a carefully regulated phase where deregulation of this process may result in insufficient or excessive bone mineralization or ectopic calcification. Osteoblasts can also be differentiated into osteocytes, populating short interconnecting passages within the bone matrix. Over the past few decades, we have seen a significant improvement in awareness and techniques using photobiomodulation (PBM) to stimulate cell function. One of the applications of PBM is the promotion of osteoblast proliferation and maturation. PBM research results on osteoblasts showed increased mitochondrial ATP production, increased osteoblast activity and proliferation, increased and pro-osteoblast expression in the presence of red and NIR radiation. Osteocyte differentiation was also accomplished using blue and green light, showing that different light parameters have various signalling effects. The current review addresses osteoblast function and control, a new understanding of PBM on osteoblasts and its therapeutic impact using various parameters to optimize osteoblast function that may be clinically important. Graphical Abstract.

Anti-Tumor Mechanisms Associated With Regulation of Non-Coding RNA by Active Ingredients of Chinese Medicine: A Review

Cancer has become the second leading cause of death worldwide; however, its complex pathogenesis remains largely unclear. Previous research has shown that cancer development and progression are closely associated with various non-coding RNAs, including long non-coding RNAs and microRNAs, which regulate gene expression. Target gene abnormalities are regulated and engaged in the complex mechanism underlying tumor formation, thereby controlling apoptosis, invasion, and migration of tumor cells and providing potentially effective targets for the treatment of malignant tumors. Chemotherapy is a commonly used therapeutic strategy for cancer; however, its effectiveness is limited by general toxicity and tumor cell drug resistance. Therefore, increasing attention has been paid to developing new cancer treatment modalities using traditional Chinese medicines, which exert regulatory effects on multiple components, targets, and pathways. Several active ingredients in Chinese medicine, including ginsenoside, baicalin, and matrine have been found to regulate ncRNA expression levels, thus, exerting anti-tumor effects. This review summarizes the scientific progress made regarding the anti-tumor mechanisms elicited by various active ingredients of Chinese medicine in regulating non-coding RNAs, to provide a theoretical foundation for treating tumors using traditional Chinese medicine.

Long Noncoding RNA OIP5-AS1 Promotes the Disease Progression in Nasopharyngeal Carcinoma by Targeting miR-203

Nasopharyngeal carcinoma (NPC) is a kind of malignancy generated from the nasopharyngeal epithelium. Recently, long noncoding RNA (lncRNA) has been shown to be involved in the regulation of many signaling pathways and is closely associated with carcinogenesis and tumor progression. However, the precise role of lncRNA Opa-interacting protein 5 antisense RNA 1 (OIP5-AS1) in NPC is not well understood. Here, we find that OIP5-AS1 is overexpressed in NPC patient specimens and NPC cell lines. Further investigations reveal that knockdown of OIP5-AS1 significantly inhibits the proliferation, migration, and invasion and accelerates the apoptosis of NPC cells in vitro. Consistent with these findings, NPC progression is significantly slowed in mice when OIP5-AS1 is knocked down. Interestingly, there is a functional link between OIP5-AS1 and microRNA-203 (miR-203), a tumor suppressor, in NPC cells. In conclusion, our data demonstrate that OIP5-AS1 plays an important role in the development and progression of NPC by targeting miR-203 and therefore provide a promising target for the treatment of NPC.

One locus with two roles: microRNA-independent functions of microRNA-host-gene locus-encoded long noncoding RNAs

Long noncoding RNAs (lncRNAs) are RNA transcripts longer than 200 nucleotides that do not code for proteins. LncRNAs play crucial regulatory roles in several biological processes via diverse mechanisms and their aberrant expression is associated with various diseases. LncRNA genes are further subcategorized based on their relative organization in the genome. MicroRNA (miRNA)-host-gene-derived lncRNAs (lnc-MIRHGs) refer to lncRNAs whose genes also harbor miRNAs. There exists crosstalk between the processing of lnc-MIRHGs and the biogenesis of the encoded miRNAs. Although the functions of the encoded miRNAs are usually well understood, whether those lnc-MIRHGs play independent functions are not fully elucidated. Here, we review our current understanding of lnc-MIRHGs, including their biogenesis, function, and mechanism of action, with a focus on discussing the miRNA-independent functions of lnc-MIRHGs, including their involvement in cancer. Our current understanding of lnc-MIRHGs strongly indicates that this class of lncRNAs could play important roles in basic cellular events as well as in diseases. This article is categorized under: Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs Regulatory RNAs/RNAi/Riboswitches > Biogenesis of Effector Small RNAs.

LncRNA H19 Regulates BMP2-Induced Hypertrophic Differentiation of Mesenchymal Stem Cells by Promoting Runx2 Phosphorylation

Objectives

Bone morphogenetic protein 2 (BMP2) triggers hypertrophic differentiation after chondrogenic differentiation of mesenchymal stem cells (MSCs), which blocked the further application of BMP2-mediated cartilage tissue engineering. Here, we investigated the underlying mechanisms of BMP2-mediated hypertrophic differentiation of MSCs.

Materials and Methods

In vitro and in vivo chondrogenic differentiation models of MSCs were constructed. The expression of H19 in mouse limb was detected by fluorescence in situ hybridization (FISH) analysis. Transgenes BMP2, H19 silencing, and overexpression were expressed by adenoviral vectors. Gene expression was determined by reverse transcription and quantitative real-time PCR (RT-qPCR), Western blot, and immunohistochemistry. Correlations between H19 expressions and other parameters were calculated with Spearman’s correlation coefficients. The combination of H19 and Runx2 was identified by RNA immunoprecipitation (RIP) analysis.

Results

We identified that H19 expression level was highest in proliferative zone and decreased gradually from prehypertrophic zone to hypertrophic zone in mouse limbs. With the stimulation of BMP2, the highest expression level of H19 was followed after the peak expression level of Sox9; meanwhile, H19 expression levels were positively correlated with chondrogenic differentiation markers, especially in the late stage of BMP2 stimulation, and negatively correlated with hypertrophic differentiation markers. Our further experiments found that silencing H19 promoted BMP2-triggered hypertrophic differentiation through in vitro and in vivo tests, which indicated the essential role of H19 for maintaining the phenotype of BMP2-induced chondrocytes. In mechanism, we characterized that H19 regulated BMP2-mediated hypertrophic differentiation of MSCs by promoting the phosphorylation of Runx2.

Conclusion

These findings suggested that H19 regulates BMP2-induced hypertrophic differentiation of MSCs by promoting the phosphorylation of Runx2.

Recombinant adenovirus (AdEasy system) mediated exogenous expression of long non-coding RNA H19 (lncRNA H19) biphasic regulating osteogenic differentiation of mesenchymal stem cells (MSCs)

BACKGROUND

We previously constructed AdEasy system for rapid generation of recombinant adenovirus expressing coding genes. However, it is unclear if AdEasy system could be used for exogenously expression of long noncoding RNAs (lncRNAs). Here we investigated how to overexpress lncRNA H19 with AdEasy system and identified the effect of overexpression H19 on mesenchymal stem cells (MSCs) osteogenic differentiation.

METHODS

H19 fragment 1 and H19 fragment 2 were amplified from mouse genomic DNA separately and then connected for full-length H19. H19 was firstly subcloned to homemade pMOK plasmid, then H19 was cut off from pMOK-H19 and subcloned to recombinant adenovirus plasmid. After homologous recombination in AdEasier cells (BJ5183 cell), packing in mammalian packaging cell line and amplification in 293pTP cells, high titer AdH19 was obtained. Immortalized mouse adipose-derived progenitors (iMADs) were infected by AdH19 with different infection rate, the expression of H19, H19 related microRNAs (miRs) and osteogenic differentiation markers were determined by TqPCR. Alkaline phosphatase (ALP) activities and matrix mineralization were determined by ALP assays and Alizarin red S staining respectively.

RESULTS

AdEasy system was suitable for rapid generation and production of H19, AdH19 can effectively overexpress H19 and serve as functional lncRNA in mesenchymal stem cells (MSCs). Higher dosage of AdH19 inhibited osteogenic differentiation of MSCs, however, lower dosage of AdH19 promoted osteogenic differentiation of MSCs.

CONCLUSIONS

We firstly reported the method for the generation of functional lncRNA with AdEasy system, and identified the biphasic effect of H19 on MSCs osteogenic differentiation.

Implications of Long Non-Coding RNAs in Age-Altered Proteostasis

This review aims to summarize the current knowledge on how lncRNAs are influencing aging and cancer metabolism. Recent research has shown that senescent cells re-enter cell-cycle depending on intrinsic or extrinsic factors, thus restoring tissue homeostasis in response to age-related diseases (ARDs). Furthermore, maintaining proteostasis or cellular protein homeostasis requires a correct quality control (QC) of protein synthesis, folding, conformational stability, and degradation. Long non-coding RNAs (lncRNAs), transcripts longer than 200 nucleotides, regulate gene expression through RNA-binding protein (RBP) interaction. Their association is linked to aging, an event of proteostasis collapse. The current review examines approaches that lead to recognition of senescence-associated lncRNAs, current methodologies, potential challenges that arise from studying these molecules, and their crucial implications in clinical practice.

LncRNA H19 gene rs2839698 polymorphism is associated with a decreased risk of colorectal cancer in a Chinese Han population: A case-control study

Background

Long non‐coding RNA (lncRNA) H19 is involved in the carcinogenesis, progression, and metastasis of colorectal cancer (CRC). Recently, a few studies explored the relationship between lncRNA H19 gene rs2839698 polymorphism and CRC risk, but with conflicting findings.

Materials and methods

A case‐control study with 315 CRC cases and 441 controls was designed in a Chinese population. Genotyping was performed using PCR‐RFLP.

Results

It was found rs2839698 polymorphism was associated with a decreased risk of CRC (AA vs GG: OR, 0.73; 95% CI, 0.54‐0.98; P = .037; A vs G: OR, 0.78; 95% CI, 0.63‐0.96; P = .021). Stratified analyses indicated this positive association was also significant in the non‐smokers (AA vs GG: OR, 0.49; 95% CI, 0.25‐0.93; P = .029), non‐drinkers, those aged ≥ 60 years, and overweight individuals (BMI ≥ 24). In addition, rs2839698 polymorphism was also related to the lymph node metastasis (AA vs GG: OR, 0.43; 95% CI, 0.21‐0.88; P = .019) and tumor size (AA vs GG: OR, 0.42; 95% CI, 0.20‐0.88; P = .020) for patients with CRC.

Conclusion

To sum up, the lncRNA H19 gene rs2839698 polymorphism decreases the risk of CRC in Chinese individuals, especially among the non‐smokers, non‐drinkers, individuals aged ≥ 60 years, and overweight individuals (BMI ≥ 24). Thus, the lncRNA H19 gene rs2839698 polymorphism might be an important biomarker and diagnostic marker for predicting the susceptibility to CRC in Chinese Han population.

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

Background

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

Methods

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

Results

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

Conclusions

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

The Neglected Insulin: IGF-II, a Metabolic Regulator with Implications for Diabetes, Obesity, and Cancer

When originally discovered, one of the initial observations was that, when all of the insulin peptide was depleted from serum, the vast majority of the insulin activity remained and this was due to a single additional peptide, IGF-II. The IGF-II gene is adjacent to the insulin gene, which is a result of gene duplication, but has evolved to be considerably more complicated. It was one of the first genes recognised to be imprinted and expressed in a parent-of-origin specific manner. The gene codes for IGF-II mRNA, but, in addition, also codes for antisense RNA, long non-coding RNA, and several micro RNA. Recent evidence suggests that each of these have important independent roles in metabolic regulation. It has also become clear that an alternatively spliced form of the insulin receptor may be the principle IGF-II receptor. These recent discoveries have important implications for metabolic disorders and also for cancer, for which there is renewed acknowledgement of the importance of metabolic reprogramming.

LncRNA MEG3 acts a biomarker and regulates cell functions by targeting ADAR1 in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is the third most prevalent malignancy and has the fourth highest global cancer mortality rate. Early diagnosis and prompt medical attention can improve quality of life and the prognosis of CRC patients. Accumulating evidence reveals that long non-coding RNAs (lncRNAs) function as oncogenes or anti-oncogenes, as well as biomarkers in various cancers.

AIM

To investigate the levels and molecular mechanism of the lncRNA maternally expressed gene 3 (MEG3) in CRC.

METHODS

The levels of lncRNA MEG3 in CRC tissue, serum and cell line samples were explored via qRT-PCR. The relationship between MEG3 levels and clinicopathological features in CRC was investigated. The diagnostic and prognostic values of serum MEG3 levels were analyzed with ROC curves and Kaplan‑Meier survival curves, respectively.

RESULTS

Significant decreased levels of MEG3 existed in CRC tissue, cell lines and serum. CRC patients with down-regulated serum MEG3 levels had larger tumor sizes, and advanced clinical stages. The sensitivity and specificity of serum MEG3 levels in CRC detection was 0.667 and 0.875, respectively. Tumor size, T stages, and serum MEG3 levels are indie factors that produce an effect on CRC patients' prognosis. Kaplan‑Meier survival curves suggested that CRC patients with high levels of MEG3 had a remarkably better overall survival rate.

CONCLUSION

LncRNA MEG3 is down-regulated in CRC, and regulates cell functions by targeting adenosine deaminase’s effect on RNA 1 in CRC.

Long non-coding RNA H19 is associated with polycystic ovary syndrome in Chinese women: a preliminary study

Polycystic ovary syndrome (PCOS) represents a serious reproductive and endocrine condition and is associated with high incidence rates. H19 is a compelling long noncoding RNA (lncRNA) which carries out a range of biological functions. However, prior to this study, little was known as to whether there was an association between lncRNA H19 and PCOS. In the current study, we used quantitative real-time polymerase chain reaction (qRT-PCR) to determine lncRNA H19 expression levels in peripheral blood leukocytes from patients with PCOS and compared this data with that derived from normal controls. We also screened data for potential relationships between lncRNA H19 and a range of endocrine variables in PCOS. The expression of lncRNA H19 was significantly higher in cases of PCOS than in controls. Individuals exhibiting higher expression levels of lncRNA H19 were associated with a significantly higher risk of PCOS than those with lower expression levels. Moreover, lncRNA H19 expression was positively correlated with fasting plasma glucose levels; this was the case with both raw data, and after adjustment for age and BMI in the PCOS group. However, lncRNA H19 expression showed no significant correlation with total testosterone or insulin resistance in either PCOS cases or the controls. In conclusion, we demonstrate the first evidence to indicate that lncRNA H19 is associated with PCOS, suggesting that elevated lncRNA H19 levels are a risk factor for PCOS. For susceptible individuals, lncRNA H19 may represent a useful biomarker of the early stages of endocrine and metabolic disorders in PCOS.

Integrated Analysis of the Altered lncRNAs and mRNAs Expression in 293T Cells after Ionizing Radiation Exposure

Tissue and cell damage caused by ionizing radiation is often highly genotoxic. The swift repair of DNA damage is crucial for the maintenance of genomic stability and normal cell fitness. Long noncoding RNAs (lncRNAs) have been reported to play an important role in many physiological and pathological processes in cells. However, the exact function of lncRNAs in radiation-induced DNA damage has yet to be elucidated. Therefore, this study aimed to analyze the potential role of lncRNAs in radiation-induced DNA damage. We examined the expression profiles of lncRNAs and mRNAs in 293T cells with or without 8 Gy irradiation using high-throughput RNA sequencing. We then performed comprehensive transcriptomic and bioinformatic analyses of these sequencing results. A total of 18,990 lncRNAs and 16,080 mRNAs were detected in all samples. At 24 h post irradiation, 49 lncRNAs and 323 mRNAs were differentially expressed between the irradiation group and the control group. qRT-PCR was used to verify the altered expression of six lncRNAs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicated that the predicted genes were mainly involved in the histone mRNA metabolic process and Wnt signaling pathways. This study may provide novel insights for the study of lncRNAs in radiation-induced DNA damage.

Long non-coding RNA H19 regulates cell growth and metastasis via miR-138 in breast cancer

Breast cancer is one of the most common cancers among women. Long non-coding RNAs (lncRNAs) are involved in the initiation and development of breast cancer and lncRNA H19 is a potential oncogenic factor; however, the underlying mechanisms remain unknown. In the present study, the regulatory functions of H19 in breast cancer were investigated. We found that H19 was upregulated in breast cancer tissues and cells and associated with poor prognosis. MiR-138 was downregulated in breast cancer tissues and negatively correlated with the expression of H19 and SOX4. Furthermore, SOX4 was upregulated in breast cancer tissues and positively correlated with H19. Downregulated H19 suppressed the proliferation, invasion and migration of breast cancer cells, but promoted cell cycle arrest and apoptosis. Additionally, miR-138 was identified as a direct target of H19 and SOX4; overexpression of miR-138 inhibited the proliferation, invasion and migration of MDA-MB-231 and MCF-7 cells, but promoted apoptosis, which were abrogated by SOX4 overexpression. Downregulated miR-138 induced cell proliferation, invasion and migration, but inhibited apoptosis of MDA-MB-231 and MCF-7 cells, which were promoted by SOX4 overexpression. In addition, miR-138 overexpression reversed the effects of H19 in breast cancer cells; silencing of H19 inhibited tumor growth and downregulate EMT markers in vivo. In summary, H19 was upregulated in breast cancer and associated with poor prognosis. Silencing of H19 inhibited cell proliferation, invasion and migration, but induced cell cycle arrest and apoptosis by regulating miR-138 and SOX4 in breast cancer.

Long noncoding RNA H19 promotes chemotherapy resistance in choriocarcinoma cells

Choriocarcinoma (CC) is a trophoblast tumor prone to early distant organ metastases. At present, the main treatment for CC is chemotherapy, but chemotherapy resistance readily occurs and leads to treatment failure. H19 is a long noncoding RNA, and its abnormal expression has been found in various tumors, including CC. H19 is also considered to be related to the drug resistance mechanism of the same cancers. To investigate the role of H19 in drug-resistant CC cells, the following experiments were designed. We used human CC cell line JEG-3 to establish cell lines resistant to methotrexate and 5-fluorouracil (JEG-3/MTX and JEG-3/5-FU) and detected the expression of H19 in JEG-3, JEG-3/MTX, JEG-3/5-FU cells, JEG-3 with MTX, and JEG-3 with 5-FU. We found that the expression of H19 in the JEG-3/MTX and JEG-3/5-FU cells were significantly higher than that in JEG-3 cells. JEG-3 cells were treated with MTX or 5-FU for and quantitative real-time polymerase chain reaction assay revealed that H19 messenger RNA expression increased. Furthermore, after H19 was knocked out, the drug resistance index of the JEG-3/MTX and JEG-3/5-FU cells decreased; the proliferation, migration, and invasion ability diminished significantly; and apoptosis increased significantly. Finally, we detected the total and phosphorylation protein expression of phosphatidylinositol-3-kinase (PI3K), protein kinase B (AKT), and mammalian target of rapamycin (mTOR) in the JEG-3/MTX and JEG-3/5-FU cells. The total protein of PI3K, AKT, and mTOR in the H19 knockout resistant cells showed no significant change relative to those in the H19 non-knockout resistant cells, whereas the phosphorylated proteins of PI3K, AKT, and mTOR were significantly decreased. Phosphorylated proteins of PI3K, AKT, and mTOR in the JEG-3/MTX and JEG-3/5-FU cells were significantly higher than that in JEG-3 cells. After using inhibition of phosphorylated PI3K/AKT/mTOR, the proliferation, migration, and invasion ability of the JEG-3/MTX and JEG-3/5-FU cells diminished significantly; and apoptosis increased significantly. On the basis of the above experiments, we concluded that H19 is related to the drug resistance of CC, and the knockout of H19 can reduce the drug resistance of resistant CC cells; and decrease the proliferative, migratory, and invasive ability; and increase the apoptosis. PI3K/AKT/mTOR pathway might be involved in H19-mediated effects. H19 is expected to be a therapeutic target for the treatment of drug-resistant chorionic carcinoma.

H19 potentiates let-7 family expression through reducing PTBP1 binding to their precursors in cholestasis

Cholestasis induces the hepatic long non-coding RNA H19, which promotes the progression of cholestatic liver fibrosis. However, microRNAs that are dysregulated by H19 during cholestasis remain elusive. Using miRNA-sequencing analysis followed by qPCR validation, we identified marked upregulation of eight members of the let-7 family in cholestatic livers by bile duct ligation (BDL) and H19 overexpression. In particular, the expression of let-7a-1/7d/7f-1 was highly induced in H19-BDL livers but decreased in H19KO-BDL livers. Interestingly, H19 decreased the nuclear let-7 precursors as well as the primary transcripts of let-7a-1/7d/7f-1 levels in BDL mouse livers. Bioinformatics, RNA pull-down, and RNA immunoprecipitation (RIP) assays revealed that the crucial RNA-binding protein polypyrimidine tract-binding protein 1 (PTBP1), an H19 interaction partner, interacted with the precursors of let-7a-1 and let-7d and suppressed their maturation. Both PTBP1 and let-7 expression was differentially regulated by different bile acid species in hepatocyte and cholangiocyte cells. Further, H19 negatively regulated PTBP1's mRNA and protein levels but did not affect its subcellular distribution in BDL mouse livers. Moreover, we found that H19 restrained but PTBP1 facilitated the bioavailability of let-7 miRNAs to their targets. Taken together, this study revealed for the first time that H19 promoted let-7 expression by decreasing PTBP1's expression level and its binding to the let-7 precursors in cholestasis.

Identification of long intergenic non-coding RNAs (lincRNAs) deregulated in gastrointestinal stromal tumors (GISTs)

Long intergenic non-coding RNAs (lincRNAs) are >200 nucleotides long non-coding RNAs, which have been shown to be implicated in carcinogenic processes by interacting with cancer associated genes or other non-coding RNAs. However, their role in development of rare gastrointestinal stromal tumors (GISTs) is barely investigated. Therefore, the aim of this study was to define lincRNAs deregulated in GIST and find new GIST-lincRNA associations. Next-generation sequencing data of paired GIST and adjacent tissue samples from 15 patients were subjected to a web-based lincRNA analysis. Three deregulated lincRNAs (MALAT1, H19 and FENDRR; adjusted p-value < 0.05) were selected for expression validation in a larger group of patients (n = 22) by RT-qPCR method. However, only H19 and FENDRR showed significant upregulation in the validation cohort (adjusted p < 0.05). Further, we performed correlation analyses between expression levels of deregulated lincRNAs and GIST-associated oncogenes or GIST deregulated microRNAs. We found high positive correlations between expression of H19 and known GIST related oncogene ETV1, and between H19 and miR-455-3p. These findings expand the knowledge on lincRNAs deregulated in GIST and may be an important resource for the future studies investigating lincRNAs functionally relevant to GIST carcinogenesis.

LncRNA H19 promotes the proliferation of pulmonary artery smooth muscle cells through AT1R via sponging let-7b in monocrotaline-induced pulmonary arterial hypertension

BACKGROUND

Pulmonary arterial hypertension (PAH) is related to inflammation, and the lncRNA H19 is associated with inflammation. However, whether PDGF-BB-H19-let-7b-AT1R axis contributes to the pathogenesis of PAH has not been thoroughly elucidated to date. This study investigated the role of H19 in PAH and its related mechanism.

METHODS

In the present study, SD rats, C57/BL6 mice and H19-/- mice were injected with monocrotaline (MCT) to establish a PAH model. H19 was detected in the cytokine-stimulated pulmonary arterial smooth muscle cells (PASMCs), serum and lungs of rats/mice. H19 overexpression and knockdown experiments were also conducted. A dual luciferase reporter assay was used to explore whether let-7b is a sponge miRNA of H19, and AT1R is a novel target of let-7b. A CCK-8 assay and flow cytometry were used to analyse cell proliferation.

RESULTS

The results showed that H19 was highly expressed in the serum and lungs of MCT-induced rats/mice, and H19 was upregulated by PDGF-BB in vitro. H19 upregulated AT1R expression via sponging miRNA let-7b following PDGF-BB stimulation. AT1R is a novel target of let-7b. Moreover, the overexpression of H19 and AT1R could facilitate PASMCs proliferation in vitro. H19 knockout protected mice from pulmonary artery remodeling and PAH following MCT treatment.

CONCLUSION

Our study showed that H19 is highly expressed in MCT-induced rodent lungs and upregulated by PDGF-BB. The H19-let-7b-AT1R axis contributed to the pathogenesis of PAH by stimulating PASMCs proliferation. The H19 knockout had a protective role in the development of PAH. H19 may be a potential tar-get for the treatment of PAH.