Long noncoding RNA MALAT1 regulates HDAC4-mediated proliferation and apoptosis via decoying of miR-140-5p in osteosarcoma cells

Osteosarcoma in a ceRNET perspective

Osteosarcoma (OS) is the most prevalent and fatal type of bone tumor. It is characterized by great heterogeneity of genomic aberrations, mutated genes, and cell types contribution, making therapy and patients management particularly challenging. A unifying picture of molecular mechanisms underlying the disease could help to transform those challenges into opportunities.This review deeply explores the occurrence in OS of large-scale RNA regulatory networks, denominated "competing endogenous RNA network" (ceRNET), wherein different RNA biotypes, such as long non-coding RNAs, circular RNAs and mRNAs can functionally interact each other by competitively binding to shared microRNAs. Here, we discuss how the unbalancing of any network component can derail the entire circuit, driving OS onset and progression by impacting on cell proliferation, migration, invasion, tumor growth and metastasis, and even chemotherapeutic resistance, as distilled from many studies. Intriguingly, the aberrant expression of the networks components in OS cells can be triggered also by the surroundings, through cytokines and vesicles, with their bioactive cargo of proteins and non-coding RNAs, highlighting the relevance of tumor microenvironment. A comprehensive picture of RNA regulatory networks underlying OS could pave the way for the development of innovative RNA-targeted and RNA-based therapies and new diagnostic tools, also in the perspective of precision oncology.

Stem-Cell-Driven Chondrogenesis: Perspectives on Amnion-Derived Cells

Regenerative medicine harnesses stem cells' capacity to restore damaged tissues and organs. In vitro methods employing specific bioactive molecules, such as growth factors, bio-inductive scaffolds, 3D cultures, co-cultures, and mechanical stimuli, steer stem cells toward the desired differentiation pathways, mimicking their natural development. Chondrogenesis presents a challenge for regenerative medicine. This intricate process involves precise modulation of chondro-related transcription factors and pathways, critical for generating cartilage. Cartilage damage disrupts this process, impeding proper tissue healing due to its unique mechanical and anatomical characteristics. Consequently, the resultant tissue often forms fibrocartilage, which lacks adequate mechanical properties, posing a significant hurdle for effective regeneration. This review comprehensively explores studies showcasing the potential of amniotic mesenchymal stem cells (AMSCs) and amniotic epithelial cells (AECs) in chondrogenic differentiation. These cells exhibit innate characteristics that position them as promising candidates for regenerative medicine. Their capacity to differentiate toward chondrocytes offers a pathway for developing effective regenerative protocols. Understanding and leveraging the innate properties of AMSCs and AECs hold promise in addressing the challenges associated with cartilage repair, potentially offering superior outcomes in tissue regeneration.

MALAT1: A Long Non-Coding RNA with Multiple Functions and Its Role in Processes Associated with Fat Deposition

Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) belongs to the lncRNA molecules, which are involved in transcriptional and epigenetic regulation and the control of gene expression, including the mechanism of chromatin remodeling. MALAT1 was first discovered during carcinogenesis in lung adenocarcinoma, hence its name. In humans, 66 of its isoforms have been identified, and in pigs, only 2 are predicted, for which information is available in Ensembl databases (Ensembl Release 111). MALAT1 is expressed in numerous tissues, including adipose, adrenal gland, heart, kidney, liver, ovary, pancreas, sigmoid colon, small intestine, spleen, and testis. MALAT1, as an lncRNA, shows a wide range of functions. It is involved in the regulation of the cell cycle, where it has pro-proliferative effects and high cellular levels during the G1/S and mitotic (M) phases. Moreover, it is involved in invasion, metastasis, and angiogenesis, and it has a crucial function in alternative splicing during carcinogenesis. In addition, MALAT1 plays a significant role in the processes of fat deposition and adipogenesis. The human adipose tissue stem cells, during differentiation into adipocytes, secrete MALAT1 as one the most abundant lncRNAs in the exosomes. MALAT1 expression in fat tissue is positively correlated with adipogenic FABP4 and LPL. This lncRNA is involved in the regulation of PPARγ at the transcription stage, fatty acid metabolism, and insulin signaling. The wide range of MALAT1 functions makes it an interesting target in studies searching for drugs to prevent obesity development in humans. In turn, in farm animals, it can be a source of selection markers to control the fat tissue content.

Beyond the genome: MALAT1's role in advancing urologic cancer care

Urologic cancers (UCs), which include bladder, kidney, and prostate tumors, account for almost a quarter of all malignancies. Long non-coding RNAs (lncRNAs) are tissue-specific RNAs that influence cell growth, death, and division. LncRNAs are dysregulated in UCs, and their abnormal expression may allow them to be used in cancer detection, outlook, and therapy. With the identification of several novel lncRNAs and significant exploration of their functions in various illnesses, particularly cancer, the study of lncRNAs has evolved into a new obsession. MALAT1 is a flexible tumor regulator implicated in an array of biological activities and disorders, resulting in an important research issue. MALAT1 appears as a hotspot, having been linked to the dysregulation of cell communication, and is intimately linked to cancer genesis, advancement, and response to treatment. MALAT1 additionally operates as a competitive endogenous RNA, binding to microRNAs and resuming downstream mRNA transcription and operation. This regulatory system influences cell growth, apoptosis, motility, penetration, and cell cycle pausing. MALAT1's evaluation and prognosis significance are highlighted, with a thorough review of its manifestation levels in several UC situations and its association with clinicopathological markers. The investigation highlights MALAT1's adaptability as a possible treatment target, providing fresh ways for therapy in UCs as we integrate existing information The article not only gathers current knowledge on MALAT1's activities but also lays the groundwork for revolutionary advances in the treatment of UCs.

Silencing circular RNA hsa_circABCC1 inhibits osteosarcoma progression through down-regulating HDAC4 via sponging miR-591

BACKGROUND

Circular RNA (circRNA) has been shown to play an important regulatory role in the development of various cancers, including osteosarcoma (OS). However, the role of circRNA ABCC1 (circABCC1) in OS was still poorly understood. The aim of our study was to investigate the role of circABCC1 in OS progression and its potential molecular mechanisms.

METHODS

The expression of circABCC1, microRNA-591 (miR-591) and histone deacetylase 4 (HDAC4) in OS tissues or cells was detected by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot (WB) analyses. In vitro experiments, the viability, proliferation, apoptosis, migration, invasion and autophagy of U2OS and HOS cells were assessed in vitro using cell counting kit-8 (CCK-8) assay, 5-ethynyl-29-deoxyuridine (EdU) assay, flow cytometry (FCM) assay, transwell migration and invasion assays (transwell) and WB assay, respectively. Interactions between circABCC1 and miR-591, miR-591 and HDAC4 were confirmed using a dual luciferase reporter gene assay system. The oncogenic role of circABCC1 in OS in vivo was examined by establishing a tumor xenograft model.

RESULTS

CircABCC1 was significantly elevated in OS tissues (about 3.1-folds) and cells (U2OS (about 2.1-folds) and HOS (about 2.8-folds)) compared with the control (p < .05). Silencing of circABCC1 significantly reduced the viability and proliferation, promoted apoptosis, impaired migration and invasion, and increased autophagy of U2OS and HOS cells (p < .05). In addition, miR-591 was confirmed to be a target of circABCC1, exerting an opposite effect to circABCC1 (p < .05). MiR-591 attenuation in U2OS and HOS cells was able to reply to the inhibition of cell proliferation, migration and invasion as well as promotion of cell apoptosis and autophagy mediated by silencing circABCC1 (p < .05). HDAC4 was verified to be the target gene of miR-591 in U2OS and HOS cells and was regulated by the circABCC1/miR-591 axis (p < .05), and restoration of HDAC4 levels in U2OS and HOS cells was able to restore the altered cellular function caused by silencing circABCC1 (p < .05). In addition, knockdown of circABCC1 attenuated tumor growth in vivo (p < .05).

CONCLUSION

Silencing of circABCC1 inhibits osteosarcoma progression by attenuating HDAC4 expression through sponging miR-591.

Intermedin induces autophagy and attenuates hypoxia-induced injury in cardiomyocytes by regulation of MALAT1/ULK1

Myocardial infarction is a predominant cause of cardiovascular diseases with high incidence and death rate worldwide. Although growing evidence has suggested that IMD has significant protective influences on the cardiovascular system, the molecular regulatory mechanism of IMD in hypoxia-induced injury caused by myocardial infarction is urgent to be elucidated. In the present study, we found hypoxia led to a noteworthy enhancement in IMD expression and IMD alleviated hypoxia-induced myocardial injury of NRCMs. Furthermore, IMD was proved to inhibit hypoxia-induced injury by regulating MALAT1. Our findings suggested MALAT1 positively regulated the mRNA and protein expression level of ULK1 and hypoxia induced autophagy of NRCMs. MALAT1 stimulated autophagy to block hypoxia-induced cell injury in NRCMs via upregulation of ULK1 expression. Autophagy suppression abolished the protective capability of IMD overexpression against hypoxia-induced myocardial injury in NRCMs. In a word, our study shed light on the central mechanism of IMD in preventing hypoxia-induced injury caused by myocardial infarction. We confirmed IMD induced autophagy and attenuated hypoxia-induced injury in cardiomyocytes via MALAT1/ULK1, which may contribute to designing effective therapeutic approaches of myocardial infarction.

LncRNA MALAT1-related signaling pathways in osteosarcoma

Osteosarcoma (OS) is a common and malignant form of bone cancer, which affects children and young adults. OS is identified by osteogenic differentiation and metastasis. However, the exact molecular mechanism of OS development and progression is still unclear. Recently, long non-coding RNAs (lncRNA) have been proven to regulate OS proliferation and drug resistance. LncRNAs are longer than 200 nucleotides that represent the extensive applications in the processing of pre-mRNA and the pathogenesis of human diseases. Metastasis-associated lung adenocarcinoma transcript-1 (MALAT1) is a well-known lncRNA known as a transcriptional and translational regulator. The aberrant expression of MALAT1 has been shown in several human cancers. The high level of MALAT1 is involved in OS cell growth and tumorigenicity by targeting several signaling pathways and miRNAs. Hence, MALAT1 might be a suitable approach for OS diagnosis and treatment. In this review, we will summarize the role of lncRNA MALAT1 in the pathophysiology of OS.

Circ_HIPK3 Inhibits H2O2-Induced Lens Epithelial Cell Injury in Age-Related Cataract Depending on the Regulation of miR-495-3p/HDAC4 Pathway

Age-related cataract (ARC) is one of the most common chronic diseases. Circular RNA (circ)_HIPK3 is reported to be involved in the advancement of ARC, but its molecular mechanism has not been clarified. Our study provides a new perspective on the clinical treatment of ARC. Our data showed that the expression levels of circ_HIPK3 and histone deacetylase 4 (HDAC4) were downregulated, while microRNA (miR)-495-3p level was increased in ARC tissues and H₂O₂-induced SRA01/04 cells. Functional experiments showed that circ_HIPK3 and HDAC4 overexpression could inhibit H₂O₂-induced lens epithelial cell apoptosis and fibrosis. In terms of mechanism, we found that circ_HIPK3 could sponge miR-495-3p, miR-495-3p could target HDAC4. Besides, we confirmed that circ_HIPK3 sponged miR-495-3p to positively regulate HDAC4. Additionally, miR-495-3p overexpression or HDAC4 knockdown reversed the inhibition effect of circ_HIPK3 on H₂O₂-induced lens epithelial cell injury. In conclusion, our data showed that circ_HIPK3 suppressed H₂O₂-induced lens epithelial cell injury by regulating miR-495-3p/HDAC4 axis.

MALAT1-miRNAs network regulate thymidylate synthase and affect 5FU-based chemotherapy

Background

The active metabolite of 5-Fluorouracil (5FU), used in the treatment of several types of cancer, acts by inhibiting the thymidylate synthase encoded by the TYMS gene, which catalyzes the rate-limiting step in DNA replication. The major failure of 5FU-based cancer therapy is the development of drug resistance. High levels of TYMS-encoded protein in cancerous tissues are predictive of poor response to 5FU treatment. Expression of TYMS is regulated by various mechanisms, including involving non-coding RNAs, both miRNAs and long non-coding RNAs (lncRNAs).

Aim

To delineate the miRNAs and lncRNAs network regulating the level of TYMS-encoded protein.

Main body

Several miRNAs targeting TYMS mRNA have been identified in colon cancers, the levels of which can be regulated to varying degrees by lncRNAs. Due to their regulation by the MALAT1 lncRNA, these miRNAs can be divided into three groups: (1) miR-197-3p, miR-203a-3p, miR-375-3p which are downregulated by MALAT1 as confirmed experimentally and the levels of these miRNAs are actually reduced in colon and gastric cancers; (2) miR-140-3p, miR-330-3p that could potentially interact with MALAT1, but not yet supported by experimental results; (3) miR-192-5p, miR-215-5p whose seed sequences do not recognize complementary response elements within MALAT1. Considering the putative MALAT1-miRNAs interaction network, attention is drawn to the potential positive feedback loop causing increased expression of MALAT1 in colon cancer and hepatocellular carcinoma, where YAP1 acts as a transcriptional co-factor which, by binding to the TCF4 transcription factor/ β-catenin complex, may increase the activation of the MALAT1 gene whereas the MALAT1 lncRNA can inhibit miR-375-3p which in turn targets YAP1 mRNA.

Conclusion

The network of non-coding RNAs may reduce the sensitivity of cancer cells to 5FU treatment by upregulating the level of thymidylate synthase.

Navigating the genomic instability mine field of osteosarcoma to better understand implications of non-coding RNAs

Osteosarcoma is one of the most genomically complex cancers and as result, it has been difficult to assign genomic aberrations that contribute to disease progression and patient outcome consistently across samples. One potential source for correlating osteosarcoma and genomic biomarkers is within the non-coding regions of RNA that are differentially expressed. However, it is unsurprising that a cancer classification that is fraught with genomic instability is likely to have numerous studies correlating non-coding RNA expression and function have been published on the subject. This review undertakes the formidable task of evaluating the published literature of noncoding RNAs in osteosarcoma. This is not the first review on this topic and will certainly not be the last. The review is organized with an introduction into osteosarcoma and the epigenetic control of gene expression before reviewing the molecular function and expression of long non-coding RNAs, circular RNAs, and short non-coding RNAs such as microRNAs, piwi RNAs, and short-interfering RNAs. The review concludes with a review of the literature and how the biology of non-coding RNAs can be used therapeutically to treat cancers, especially osteosarcoma. We conclude that non-coding RNA expression and function in osteosarcoma is equally complex to understanding the expression differences and function of coding RNA and proteins; however, with the added lens of both coding and non-coding genomic sequence, researchers can begin to identify the patterns that consistently associate with aggressive osteosarcoma.

Silencing circular RNAPTPN12 promoted the growth of keloid fibroblasts by activating Wnt signaling pathway via targeting microRNA-21-5p

Keloid is a skin disease marked by fibroplasia, and fibroblasts viability plays a considerable part in keloid. Our research was devoted to assessing the involvement and mechanism of circPTPN12 in keloid. The level of circPTPN12 and miR-21-5p was estimated by qRT-PCR in keloid tissues and cells. MTT analysis was devoted to evaluating the multiplication of keloid fibroblasts. Additionally, transwell assay was dedicated to verifying cell migration and invasion. Furthermore, keloid fibroblasts apoptosis level was assessed adopting flow cytometry, and the relevancy between miR-21-5p and circPTPN12, miR-21-5p, and SMAD7 was assessed by dual luciferase assay. Similarly, RIP and RNA pull-down assay verified the relevance between genes. Moreover, levels of SMAD7 and proteins concerned in Wnt signaling pathway were appraised by Western blot. The level of circPTPN12 declined in keloid. circPTPN12 knockout could enhance the multiplication, migration, invasion, and decline apoptosis of keloid fibroblasts. Indeed, miR-21-5p could be packed with circPTPN12 sponge, SMAD7 was downstream effect factor of miR-21-5p, and miR-21-5p inhibitors partially reversed the promoting effect of silencing circPTPN12 on keloid formation. Otherwise, the level of SMAD7 was adjusted by circPTPN12 and miR-21-5p. Silencing circPTPN12 targeted miR-21-5p and activated Wnt pathway to accelerate keloid fibroblasts growth. Taken together, silencing circPTPN12 promotes the growth of keloid fibroblasts by activating Wnt pathway targeting miR-21-5p. CircPTPN12 may play a considerable part in keloid formation, which supplies a reference for molecularly targeted therapy keloid.

The Multiple Function of lncRNA MALAT1 in Cancer Occurrence and Progression

Long non-coding RNAs (lncRNAs) have received particular attention in the last decade due to its engaging in carcinogenesis and tumorigenesis. Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a lncRNA that plays physiological and pathological roles in many aspects of genome function as well as biological processes involved in cell development, differentiation, proliferation, invasion, and migration. In this article, we will review the effects of lncRNA MALAT1 on the progression of six prevalent human cancers by focusing on MALAT1 ability to regulate post-transcriptional modification and signaling pathways.

LncRNA MALAT1 Promotes Tumor Angiogenesis by Regulating MicroRNA-150-5p/VEGFA Signaling in Osteosarcoma: In-Vitro and In-Vivo Analyses

The present study aims to analyze the expression of long noncoding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in human osteosarcoma (OS) cells and to investigate its role in OS-induced angiogenesis. MALAT1 expression in OS cells was significantly higher than in normal osteoblasts. The functional analysis indicated that MALAT1 appears to enhance OS-induced angiogenesis, in vitro and in vivo analyses, endothelial cell proliferation and migration, chick embryo angiogenesis assay, and zebrafish xenograft model. Mechanistically, silencing MALAT1 downregulated vascular endothelial growth factor A (VEGFA) expression and upregulated miR-150-5p expression in OS cells, and MALAT1-mediated angiogenic induction by VEGFA in OS microenvironment. Moreover, MALAT1 directly targeted miR-150-5p and miR-150-5p directly target VEGFA in OS. Overexpression of miR-150-5p downregulates VEGFA expression in OS. More notably, we showed that MALAT1 induced angiogenesis in OS microenvironment by upregulating the expression of VEGFA via targeting miR-150-5p. Overall, our findings suggest that MALAT1 promotes angiogenesis by regulating the miR-150-5p/VEGFA signaling in OS microenvironment. The findings of the molecular mechanisms of MALAT1 in tumor angiogenesis offer a new viewpoint on OS treatment.

Circulating Long Non-Coding RNAs as Novel Potential Biomarkers for Osteogenic Sarcoma

Circulating cell-free nucleic acids recently became attractive targets to develop non-invasive diagnostic tools for cancer detection. Along with DNA and mRNAs, transcripts lacking coding potential (non-coding RNAs, ncRNAs) directly involved in the process of tumor pathogenesis have been recently detected in liquid biopsies. Interestingly, circulating ncRNAs exhibit specific expression patterns associated with cancer and suggest their role as novel biomarkers. However, the potential of circulating long ncRNAs (c-lncRNAs) to be markers in osteosarcoma (OS) is still elusive. In this study we performed a systematic review to identify thirteen c-lncRNAs whose altered expression in blood associate with OS. We herein discuss the potential impact that these c-lncRNAs may have on clinical decision-making in the management of OS. Overall, we aimed to provide novel insights that can contribute to the development of future precision medicine in oncology.

Downregulation of miR-29b-3p aggravates podocyte injury by targeting HDAC4 in LPS-induced acute kidney injury

Sepsis is a severe organ dysfunction disease, usually accompanied by acute kidney injury (AKI). miR-29b-3p was inhibited in sepsis-induced AKI, while its role in AKI was unclear. Therefore, this study determined the role of miR-29b-3p in sepsis-induced AKI, and investigated its underlying mechanism. In this study, the AKI model was established through injecting with lipopolysaccharides (LPS) intraperitoneally. In LPS challenged mice, serum blood urea nitrogen and creatinine were increased, and renal tissues pathological damage was induced. Besides, miR-29b-3p was declined in LPS-induced AKI mice and podocytes. In addition, HDAC4 was elevated in LPS-treated podocytes. Furthermore, upregulated miR-29b-3p attenuated LPS-induced mice podocyte injury, and HDAC4 was identified as a direct target of miR-29b-3p. Moreover, overexpression of miR-29b-3p attenuated LPS-induced AKI in mice. In conclusion, miR-29b-3p was inhibited in LPS-induced AKI. Downregulation of miR-29b-3p aggravated podocyte injury through targeting HDAC4 in LPS-induced AKI. miR-29b-3p may act as a valuable target for AKI therapy.

The Involvement of Long Non-Coding RNAs in Bone

A harmonious balance between osteoblast and osteoclast activity guarantees optimal bone formation and resorption, pathological conditions affecting the bone may arise. In recent years, emerging evidence has shown that epigenetic mechanisms play an important role during osteoblastogenesis and osteoclastogenesis processes, including long non-coding RNAs (lncRNAs). These molecules are a class of ncRNAs with lengths exceeding 200 nucleotides not translated into protein, that have attracted the attention of the scientific community as potential biomarkers to use for the future development of novel diagnostic and therapeutic approaches for several pathologies, including bone diseases. This review aims to provide an overview of the lncRNAs and their possible molecular mechanisms in the osteoblastogenesis and osteoclastogenesis processes. The deregulation of their expression profiles in common diseases associated with an altered bone turnover is also described. In perspective, lncRNAs could be considered potential innovative molecular biomarkers to help with earlier diagnosis of bone metabolism-related disorders and for the development of new therapeutic strategies.

The value of lncRNAs as prognostic biomarkers on clinical outcomes in osteosarcoma: a meta-analysis

Background

In recent years, emerging studies have demonstrated critical functions and potential clinical applications of long non-coding RNA (lncRNA) in osteosarcoma. To further validate the prognostic value of multiple lncRNAs, we have conducted this updated meta-analysis.

Methods

Literature retrieval was conducted by searching PubMed, Web of Science and the Cochrane Library (last update by October 2, 2019). A meta-analysis was performed to explore association between lncRNAs expression and overall survival (OS) of osteosarcoma patients. Relationships between lncRNAs expression and other clinicopathological features were also analyzed respectively.

Results

Overall, 4351 patients from 62 studies were included in this meta-analysis and 25 lncRNAs were identified. Pooled analyses showed that high expression of 14 lncRNAs connoted worse OS, while two lncRNAs were associated with positive outcome. Further, analysis toward osteosarcoma clinicopathologic features demonstrated that overexpression of TUG1 and XIST indicated poor clinical parameters of patients.

Conclusions

This meta-analysis has elucidated the prognostic potential of 16 lncRNAs in human osteosarcoma. Evidently, desperate expression and functional targets of these lncRNAs offer new approaches for prognosis and therapy of osteosarcoma.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-07882-w.

LncRNA-NONHSAT024778 promote the proliferation and invasion of chordoma cell by regulating miR-1290/Robo1 axis

Chordoma is a malignant bone tumor originating from the embryonic remnants of the notochord. lncRNAs act as competing endogenous RNAs (ceRNAs) and play a critical role in tumor pathology. However, the biological role of lncRNA-NONHSAT024778 and the underlying molecular mechanism in chordoma remains unknown. qRT-PCR was used to analyze the expression changes of NONHSAT024778 and miR-1290 in chordoma tissues and cell lines. Bioinformatics analysis and luciferase reporter assay were applied to detect the targeting binding effect between NONHSAT024778 and miR-1290, and between Robo1 and miR-1290. The effect of NONHSAT024778 on chordoma cell proliferation and invasion and its regulation of miR-1290 by acting as a ceRNA were also investigated. An increased NONHSAT024778 expression was correlated with a decreased miR-1290 level in chordoma tissues. NONHSAT024778 knockdown suppressed the proliferation and invasion of chordoma cells. miR-1290 restored expression rescued the carcinogenic function of NONHSAT024778. Bioinformatics analysis showed that NONHSAT024778 acted as ceRNA to regulate Robo1 via sponging miR-1290 in chordoma cells, thereby promoting chordoma cell malignant progression. In vivo results confirmed the anti-tumor effects of NONHSAT024778 knockdown activating miR-1290 to inhibit the oncogene Robo1. NONHSAT024778 is substantially overexpressed, whereas miR-1290 is decreased in chordoma tissue. NONHSAT024778-miR-1290-Robo1 axis plays a critical role in chordoma tumorigenesis and might be a potential predictive biomarker for the diagnosis and therapeutic target among patients with chordoma.

microRNA-140: A miRNA with diverse roles in human diseases

MicroRNA-140 (miR-140) has been shown to be associated with the pathogenesis of a wide range of pathologies including osteoarthritis, osteoporosis, renal fibrosis, ischemic conditions, and most importantly neoplasia. This miRNA has been shown to be down-regulated in a diversity of cancers namely breast cancer, gastrointestinal cancers, lung cancer, and prostate cancer. miR-140 has a lot of immune-related targets. Moreover, several miR-140 targets regulate cell proliferation, cell cycle transition, and apoptosis. This miRNA has been shown to be sponged by a number of lncRNAs and circ-RNAs. miR-140 has essential roles in the determination of the sensitivity of neoplastic cells to chemotherapeutic agents such as temozolomide, doxorubicin, and cisplatin. Besides, expression quantities of miR-140 in cancer tissues can be used for the prediction of clinical outcomes of patients with neoplasia. In the present paper, we describe the impact of miR-140 in neoplastic and non-neoplastic disorders.

Regulatory Networks of LncRNA MALAT-1 in Cancer

Long noncoding (lnc)RNAs are a group of RNAs with a length greater than 200 nt that do not encode a protein but play an essential role in regulating the expression of target genes in normal biological contexts as well as pathologic processes including tumorigenesis. The lncRNA metastasis-associated lung adenocarcinoma transcript (MALAT)-1 has been widely studied in cancer. In this review, we describe the known functions of MALAT-1; its mechanisms of action; and associated signaling pathways and their clinical significance in different cancers. In most malignancies, including lung, colorectal, thyroid, and other cancers, MALAT-1 functions as an oncogene and is upregulated in tumors and tumor cell lines. MALAT-1 has a distinct mechanism of action in each cancer type and is thus at the center of large gene regulatory networks. Dysregulation of MALAT-1 affects cellular processes such as alternative splicing, epithelial–mesenchymal transition, apoptosis, and autophagy, which ultimately results in the abnormal cell proliferation, invasion, and migration that characterize cancers. In other malignancies, such as glioma and endometrial carcinoma, MALAT-1 functions as a tumor suppressor and thus forms additional regulatory networks. The current evidence indicates that MALAT-1 and its associated signaling pathways can serve as diagnostic or prognostic biomarker or therapeutic target in the treatment of many cancers.

Long non-coding RNA PGM5-AS1 promotes epithelial-mesenchymal transition, invasion and metastasis of osteosarcoma cells by impairing miR-140-5p-mediated FBN1 inhibition

Osteosarcoma is an uncommon tumor occurring in bone, accompanied by elevated incidence and reduced rate of healing. Epithelial‐to‐mesenchymal transition (EMT) serves as a conceptual paradigm to explain the invasion and metastasis of osteosarcoma and other cancers. Hence, developing effective therapeutic strategy to treat the EMT of osteosarcoma is essential. Here, we identified the molecular mechanism of long noncoding RNA (lncRNA) PGM5‐AS1 in EMT and progression of osteosarcoma. Microarray‐based analysis was employed to screen the osteosarcoma‐related differentially expressed lncRNAs. The levels of PGM5‐AS1 as well as microRNA‐140‐5p (miR‐140‐5p) and fibrillin‐1 (FBN1) in osteosarcoma tissues and cells were determined. Dual‐luciferase reporter gene assay, RNA pull‐down assay, and RNA immunoprecipitation assay were conducted to validate the relationship among PGM5‐AS1, miR‐140‐5p, and FBN1. Expression of PGM5‐AS1, miR‐140‐5p, and FBN1 was altered by overexpression, shRNA, mimic, or inhibitors in order to investigate how they regulated migration, invasion, and EMT of osteosarcoma cells in vitro. Loss‐ and gain‐of‐function approaches were employed in nude mice to detect their roles in tumorigenesis in vivo. Osteosarcoma tissues and cells exhibited low expression of miR‐140‐5p, but high expression of PGM5‐AS1 and FBN1. PGM5‐AS1 competitively bound to miR‐140‐5p to upregulate FBN1. Furthermore, hindering PGM5‐AS1 and FBN1 or overexpressing miR‐140‐5p dampened migration, invasion, and EMT of osteosarcoma cells in vitro. Furthermore, silencing PGM5‐AS1 or FBN1, or overexpressing miR‐140‐5p markedly inhibited tumorigenesis in nude mice in vivo. Taken together, PGM5‐AS1 depletion causes FBN1 reduction to retard osteosarcoma processes by negatively modulating miR‐140‐5p.

Recent progress on the role of miR-140 in cartilage matrix remodelling and its implications for osteoarthritis treatment

Cartilage matrix remodelling homeostasis is a crucial factor in maintaining cartilage integrity. Loss of cartilage integrity is a typical characteristic of osteoarthritis (OA). Strategies aimed at maintaining cartilage integrity have attracted considerable attention in the OA research field. Recently, a series of studies have suggested dual functions of microRNA-140 (miR-140) in cartilage matrix remodelling. Here, we discuss the significance of miR-140 in promoting cartilage formation and inhibiting degeneration. Additionally, we focused on the role of miR-140 in the chondrogenesis of mesenchymal stem cells (MSCs). Of note, we carefully reviewed recent advances in MSC exosomes for miRNA delivery in OA treatment.

Long non-coding RNA MALAT1 promotes odontogenic differentiation of human dental pulp stem cells by impairing microRNA-140-5p-dependent downregulation of GIT2

Accumulating research continues to highlight the notable role of microRNAs (miRs) and long non-coding RNAs (lncRNAs) as important regulators in the process of human dental pulp stem cell (hDPSCs) differentiation. The current study aimed to investigate the novel regulatory circuitry of lncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1)/miR-140-5p/G protein-coupled receptor (GPCR)-kinase 2 interacting protein 2 (GIT2) on the odontogenic differentiation of hDPSCs. In hDPSCs, miR-140-5p was downregulated during the odontogenic differentiation, which was verified to directly target GIT2. RNA crosstalk determined by dual-luciferase reporter and RNA pull-down assays revealed that MALAT1 could bind to miR-140-5p to upregulate the expression of GIT2. After that, the levels of MALAT1, miR-140-5p, and GIT2 in hDPSCs were up- or downregulated by exogenous transfection or lentivirus infection in order to investigate their effects on the differentiation of hDPSCs. It was observed that elevation of miR-140-5p or knockdown of GIT2 resulted in inhibited alkaline phosphatase (ALP) activity, expression of dentin sialophosphoprotein (DSPP), dentin matrix-protein-1 (DMP-1), and distal-less homeobox 3 (DLX3) as well as positive expression of desmoplakin (DSP) protein. The promotive effects of MALAT1 on odontogenic differentiation were diminished by restoration of miR-140-5p or inhibition of GIT2. Taken together, this study provides valuable evidence suggesting MALAT1 as a potential contributor to the odontogenic differentiation of hDPSCs.

Long Noncoding RNA LINC00460 Facilitates Colorectal Cancer Progression by Negatively Regulating miR-613

Background

Long-noncoding RNAs (lncRNAs) could exert a crucial effect on the development of human cancers, including CRC. However, the biological function and underlying mechanism of LINCRNA00460 in the development of CRC still need deeper exploration.

Materials and Methods

The expression of LINC00460 in CRC tissues and cell lines was assessed by qRT-PCR. Cell proliferation, migration, and invasion were measured by the respective cell counting Kit-8 (CCK-8), wound healing assay and transwell invasion assay. Cell apoptosis and caspase-3 activity were detected by flow cytometry and caspase-3 activity assay. The relationship between LINC00460 and miR-613 expression was explored by Dual-luciferase reporter assay. Protein expression was measured by Western blotting. In vivo tumour growth was evaluated using a xenograft model of nude mice.

Results

LINC00460 was markedly up-regulated in CRC tissues and cell lines compared to their corresponding controls, which was closely correlated with clinical stage, TNM (T) classification, nodal (N) classification, metastasis (M) classification, liver metastasis and pathological differentiation, and survival rate of CRC patients. Functionally, LINC00460 knockdown decreased the proliferative, migrative and invasive abilities, and enhanced apoptosis rates and caspase-3 activity in HT29 and LOVO cells. Mechanistic studies indicated that miR-613 was targeted by LINC00460, and SphK1 was targeted and inversely regulated by miR-613 in HT29 and LOVO cells. In vivo studies, LINC00460 knockdown attenuated tumour growth. MiR-613 downregulation and SphK1 upregulation in the CRC tissues, and LINC00460 expression levels were inversely correlated with miR-613 expression and positively correlated with the SphK1 mRNA expression. Overall, LINC00460 modulated cell proliferation, migration, invasion and sphingosine kinase 1 (SphK1) expression in HT29 and LOVO cells, at least in most part, by regulating miR‐613.

Conclusion

LINC00460 functions as a competing endogenous RNA to regulate SphK1 expression by sponging miR‐613 in CRC and provides a valuable therapeutic strategy for CRC patients.

OIP5-AS1 modulates epigenetic regulator HDAC7 to enhance non-small cell lung cancer metastasis via miR-140-5p

Long non-coding RNAs have been reported to be involved in non-small cell lung cancer (NSCLC) progression. However, whether Opa-interacting protein 5 antisense RNA 1 (OIP5-AS1) serves a role in NSCLC remains unclear. Bioinformatics analysis of The Cancer Genome Atlas datasets showed clinical significance and relevance of OIP5-AS1 in NSCLC. Western blotting and reverse transcription-quantitative PCR revealed protein and RNA expression levels of the genes [including OIP5-AS1, microRNA (miR)-140-5p, histone deacetylase 7 (HDAC7) and vascular endothelial growth factor A (VEGFA)]. Direct associations between the genes (miR-140-5p and OIP5-AS1, or miR-140-5p and HDAC7) were confirmed using a dual-luciferase reporter assay. Lymphatic vessel formation and invasion ability were detected using a lymphatic vessel formation assay and Transwell invasion assay. OIP5-AS1 knockdown attenuated lymphatic vessel length and invasion. The role of OIP5-AS1 was reverted by miR-140-5p. HDAC7 and VEGFA are downstream effectors of miR-140-5p-mediated NSCLC metastasis. OIP5-AS1, miR-140-5p, HDAC7 and VEGFA were all dysregulated in human clinical NSCLC tumor tissues. In conclusion, the present results demonstrated a novel mechanism for OIP5-AS1-induced metastatic phenotypes of NSCLC via the miR-140-5p/HDAC7/VEGFA axis.

LPS-treatment of bovine endometrial epithelial cells causes differential DNA methylation of genes associated with inflammation and endometrial function

Background

Lipopolysaccharide (LPS) endotoxin stimulates pro-inflammatory pathways and is a key player in the pathological mechanisms involved in the development of endometritis. This study aimed to investigate LPS-induced DNA methylation changes in bovine endometrial epithelial cells (bEECs), which may affect endometrial function. Following in vitro culture, bEECs from three cows were either untreated (0) or exposed to 2 and 8 μg/mL LPS for 24 h.

Results

DNA samples extracted at 0 h and 24 h were sequenced using reduced representation bisulfite sequencing (RRBS). When comparing DNA methylation results at 24 h to time 0 h, a larger proportion of hypomethylated regions were identified in the LPS-treated groups, whereas the trend was opposite in controls. When comparing LPS groups to controls at 24 h, a total of 1291 differentially methylated regions (DMRs) were identified (55% hypomethylated and 45% hypermethylated). Integration of DNA methylation data obtained here with our previously published gene expression data obtained from the same samples showed a negative correlation (r = − 0.41 for gene promoter, r = − 0.22 for gene body regions, p < 0.05). Differential methylation analysis revealed that effects of LPS treatment were associated with methylation changes for genes involved in regulation of immune and inflammatory responses, cell adhesion, and external stimuli. Gene ontology and pathway analyses showed that most of the differentially methylated genes (DMGs) were associated with cell proliferation and apoptotic processes; and pathways such as calcium-, oxytocin- and MAPK-signaling pathways with recognized roles in innate immunity. Several DMGs were related to systemic inflammation and tissue re-modelling including HDAC4, IRAK1, AKT1, MAP3K6, Wnt7A and ADAMTS17.

Conclusions

The present results show that LPS altered the DNA methylation patterns of bovine endometrial epithelial cells. This information, combined with our previously reported changes in gene expression related to endometrial function, confirm that LPS activates pro-inflammatory mechanisms leading to perturbed immune balance and cell adhesion processes in the endometrium.

LncRNAs GACAT3 and LINC00152 regulate each other through miR-103 and are associated with clinicopathological characteristics in colorectal cancer

BACKGROUND

Long non-coding RNAs (lncRNAs) perform pivotal regulatory roles in tumor development. Our previous work revealed that the lncRNA gastric cancer-associated transcript 3 (GACAT3) was significantly overexpressed and associated with tumor size and metastasis in gastric cancer.

METHODS

Total RNAs were extracted from colorectal cancer (CRC) and reverse transcribed, and then quantitative real-time PCR (qRT-PCR) was conducted. Cell counting was performed to assess the effect of GACAT3 on CRC cell line proliferation. Bioinformatics prediction, dual luciferase assay, miRNA mimics, siRNAs, and transfection experiments were applied to determine whether GACAT3 and LINC00152 are reciprocally regulated by miR-103. The relationship between their expression levels and clinicopathological factors of patients was explored. A receiver operating characteristic (ROC) curve was used to assess the potential diagnostic value of GACAT3 and LINC00152.

RESULTS

GACAT3 was identified to be highly expressed in CRC tissues and associated with cell proliferation. Furthermore, we demonstrated that GACAT3 acted as a competing endogenous RNA of LINC00152 and they were both regulated by miR-103. Moreover, analysis of clinicopathological characteristics revealed that GACAT3 and LINC00152 were positively correlated with the depth of invasion, TNM stage, lymph node metastasis, and CA19-9 level. Importantly, a combination of GACAT3 and LINC00152 showed a superior diagnostic capacity compared with the use of the two molecules alone.

CONCLUSION

Our work shows that GACAT3 and LINC00152 are both overexpressed in CRC and they act as a ceRNA network. Therefore, our data suggest that GACAT3 and LINC00152 may be a promising potential diagnostic biomarker for CRC.

Long Noncoding RNA MALAT1 Contributes to Sorafenib Resistance by Targeting miR-140-5p/Aurora-A Signaling in Hepatocellular Carcinoma

Long noncoding RNAs (lncRNA) have been found to play critical roles in tumorigenesis and the development of various cancers, including hepatocellular carcinoma (HCC). Metastasis associated with lung adenocarcinoma transcript-1 (MALAT1) has been identified as an oncogene and prognostic biomarker in HCC. Here, we demonstrated that MALAT1 expression was obviously high in sorafenib-resistant HCC cells. Furthermore, knockdown of MALAT1 increased sorafenib sensitivity in nonresponsive HCC cells, whereas forced expression of MALAT1 conferred sorafenib resistance to responsive HCC cells in vitro In addition, loss/gain-of-function assays revealed that MALAT1 promoted cell proliferation, migration, and epithelial-mesenchymal transition in HCC cells. Mechanistically, MALAT1 regulated Aurora-A expression by sponging miR-140-5p, thus promoting sorafenib resistance in HCC cells. Moreover, MALAT1 inhibition enhanced the antitumor efficacy of sorafenib in vivo Clinically, we found that MALAT1 expression was negatively correlated with miR-140-5p expression but positively correlated with Aurora-A expression in patients with HCC and that upregulated MALAT1 was closely correlated with poor survival outcomes in patients with HCC. These findings indicated that MALAT1 may be a novel target for prognosis prediction and therapeutic strategies in patients with HCC treated with sorafenib.

Long intergenic non‑protein coding RNA 00460 predicts a poor prognosis and promotes tumorigenesis of human osteosarcoma

Osteosarcoma (OS) is the most common type of primary malignant bone tumor, which has a high incidence rate in children and adolescents. This research aims to reveal the role of long intergenic non‑protein coding RNA 00460 (LINC00460) in OS by the loss‑of‑function experiment. LINC00460 is involved in the development of multiple types of tumor, but the role of LINC00460 in OS is unclear. To discover more effective molecular targets for the treatment of OS, the association between LINC00460 and OS prognosis was analyzed using the Gene Expression Profiling Interactive Analysis database. Additionally, small interfering RNA was used to knockdown LINC00460 gene expression in vitro to verify its biological effects on the viability, invasive and migratory potential of OS cells. LINC00460 knockdown significantly reduced the viability of OS cells and initiated cell cycle arrest within the G0/G1 phase through the decreased expression of cyclin D1 and CDK4/CDK6. In addition, LINC00460 knockdown promoted apoptosis of OS cells, and inhibited the migratory and invasive abilities of OS cells through the inhibition of the epithelial‑mesenchymal transition pathway. In conclusion, the present study reported that LINC00460 may predict OS prognosis, and may serve an important role in mediating the viability, invasive and migratory potential of OS cells. Based on these findings, LINC00460 demonstrated promising potential as a future therapeutic target for OS treatment.

Metastasis Associated Lung Adenocarcinoma Transcript 1: An update on expression pattern and functions in carcinogenesis

The Metastasis Associated Lung Adenocarcinoma Transcript 1 (MALAT1) is among long non-coding RNAs (lncRNAs) which has disapproved the old term of "junk DNA" which was used for majority of human genome which are not transcribed to proteins. An extensive portion of literature points to the fundamental role of this lncRNA in tumorigenesis process of diverse cancers ranging from solid tumors to leukemia. Being firstly identified in lung cancer, it has prognostic and diagnostic values in several cancer types. Consistent with the proposed oncogenic roles for this lncRNA, most of studies have shown up-regulation of MALAT1 in malignant tissues compared with non-malignant/normal tissues of the same source. However, few studies have shown down-regulation of MALAT1 in breast cancer, endometrial cancer, colorectal cancer and glioma. In the current study, we have conducted a comprehensive literature search and provided an up-date on the role of MALAT1 in cancer biology. Our investigation underscores a potential role as a diagnostic/prognostic marker and a putative therapeutic target for MALAT1.

Long non-coding RNA MALAT1 promotes angiogenesis and immunosuppressive properties of HCC cells by sponging miR-140

Hepatocellular carcinoma (HCC) is the most prevalent primary liver cancer in adults. Previous studies in our laboratory found that long non-coding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) was upregulated in HCC cells, which could affect the metastasis and invasion of HCC. However, the underlying mechanism remains unknown. Herein, we studied the interaction between MALAT1 and miR-140 on the regulation of angiogenesis and immunosuppressive properties. We revealed that the expression of MALAT1 and VEGF-A was significantly increased in HCC cells. Knockdown of MALAT1 in HCC cells suppressed the production of VEGF-A, impaired the angiogenesis of HUVECs, and facilitated the polarization of macrophage toward the M1 subset. Mechanistically, the interaction between MALAT1 and miR-140 or between miR-140 and VEGF-A was confirmed by multiple assays. Besides, a negative correlation between MALAT1 and miR-140 was found in HCC tissues. Furthermore, miR-140 inhibition significantly increased VEGF-A expression, promoted angiogenesis of HUVECs, and redirected the polarization of macrophages toward the M2 subset. In addition, in vivo studies also verified the regulatory network of the MALAT1/miR-140 axis on VEGF-A in HCC progression. In summary, this study revealed the mechanism that MALAT1 worked as a putative HCC promotor via inhibiting miR-140. Therefore, targeting MALAT1 or miR-140 might alleviate the progression of HCC in the future.

LncRNA MALAT1 acts as a miR-125a-3p sponge to regulate FOXM1 expression and promote hepatocellular carcinoma progression

Background: Hepatocellular carcinoma (HCC) is a prominent cancer type, with long non-coding RNAs (lncRNAs) being known to be relevant to its progression. We therefore investigated how a particular lncRNA known as the metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) was associated with HCC.

Methods: Quantitative reverse transcriptase PCR (qPCR) was used to assess expression of MALAT1, Forkhead Box M1 (FOXM1) and miR-125a-3p in HCC tissue samples. How MALAT1 regulates HCC proliferation and metastasis was assessed through appropriate assays. FOXM1 was identified as a miR-125a-3p target using luciferase assays, and how MALAT1/miR-125a-3p alter FOXM1 expression was explored via qPCR and Western blotting.

Results: HCC tissues exhibited MALAT1 upregulation. miR-125a-3p targeted FOXM1 and could be regulated by MALAT1. MALAT1 knockdown disrupted proliferation and invasion, whereas miR-125a-3p knockdown partially reversed this phenotype.

Conclusions: These results indicate that MALAT1 modulates FOXM1 expression via being a miR-125a-3p sponge, thus promoting HCC progression.

The posttranslational modification of HDAC4 in cell biology: Mechanisms and potential targets

Histone deacetylase 4 (HDAC4) is a member of the HDACs family, its expression is closely related to the cell development. The cell is an independent living entity that undergoes proliferation, differentiation, senescence, apoptosis, and pathology, and each process has a strict and complex regulatory system. With deepening of its research, the expression of HDAC4 is critical in the life process. This review focuses on the posttranslational modification of HDAC4 in cell biology, providing an important target for future disease treatment.

Non-Coding RNAs in Pediatric Solid Tumors

Pediatric solid tumors are a diverse group of extracranial solid tumors representing approximately 40% of childhood cancers. Pediatric solid tumors are believed to arise as a result of disruptions in the developmental process of precursor cells which lead them to accumulate cancerous phenotypes. In contrast to many adult tumors, pediatric tumors typically feature a low number of genetic mutations in protein-coding genes which could explain the emergence of these phenotypes. It is likely that oncogenesis occurs after a failure at many different levels of regulation. Non-coding RNAs (ncRNAs) comprise a group of functional RNA molecules that lack protein coding potential but are essential in the regulation and maintenance of many epigenetic and post-translational mechanisms. Indeed, research has accumulated a large body of evidence implicating many ncRNAs in the regulation of well-established oncogenic networks. In this review we cover a range of extracranial solid tumors which represent some of the rarer and enigmatic childhood cancers known. We focus on two major classes of ncRNAs, microRNAs and long non-coding RNAs, which are likely to play a key role in the development of these cancers and emphasize their functional contributions and molecular interactions during tumor formation.

MALAT1 accelerates the development and progression of renal cell carcinoma by decreasing the expression of miR-203 and promoting the expression of BIRC5

OBJECTIVE

We aimed to investigate the roles of the lncRNA MALAT1 in renal cell carcinoma (RCC) progression.

METHODS

qRT-PCR was used for the assessment of BIRC5, miRNA-203 and MALAT1 expression. Furthermore, the targeted relationships between miR-203 and BIRC5, as well as MALAT1 and miR-203, were predicted by the miRanda/starBase database and verified by dual-luciferase reporter gene assay. The effects of MALAT1, miRNA-203 and BIRC5 on cell proliferation, cell cycle, cell apoptosis, cell invasion and cell migration were studied by using CCK-8, flow cytometry, transwell and wound healing assays, respectively. In addition, the effects of MALAT1 on RCC tumorigenesis were evaluated in vivo by nude mouse tumorigenesis.

RESULTS

The expression levels of BIRC5 and MALAT1 were higher in RCC tissues and cell lines than in adjacent normal tissues and a normal renal cortex proximal tubule epithelial cell line. In contrast, the expression of miRNA-203 in RCC tissues and cell lines was higher than that in adjacent normal tissues and a normal renal cortex proximal tubule epithelial cell line. BIRC5 and MALAT1 promoted cell proliferation yet decreased the percentage of RCC cells at G0/G1 phase.

CONCLUSIONS

Our study demonstrated that MALAT1 functions as a miR-203 decoy to increase BIRC5 expression in RCC.

Functional role of long non-coding RNA CASC19/miR-140-5p/CEMIP axis in colorectal cancer progression in vitro

BACKGROUND

Long non-coding RNAs (lncRNAs) are widely involved in tumor regulation. Nevertheless, the role of the lncRNA cancer susceptibility 19 (CASC19) in colorectal cancer (CRC) has yet to be fully clarified.

AIM

To explore the effect of CASC19 on proliferation and metastasizing ability of CRC cells.

METHODS

CASC19 expression in human CRC tissues, pair-matched adjacent normal colon tissues, and CRC cells was detected using quantitative real-time PCR (qRT-PCR). CASC19 expression, as well as its relation to overall survival, was extrapolated by Kaplan-Meier survival analysis together with multivariable Cox regression assay. In vitro experiments were performed to confirm whether CASC19 regulates CRC cell invasion, migration, proliferation, and apoptosis.

RESULTS

CASC19 expression was markedly upregulated in CRC tissues and CRC cell lines (P < 0.05). qRT-PCR revealed that CASC19 expression was higher in 25 tissue samples from patients with aggressive CRC compared with the 27 tissue samples from patients with nonaggressive CRC (P < 0.05). Higher CASC19 expression was associated with poorer patient prognoses. Furthermore, in vitro experiments demonstrated that CASC19 overexpression enhanced CRC cell invasion, migration, and proliferation. CASC19 overexpression enhanced the expression of cell migration inducing hyaluronidase 1 (CEMIP) and epithelial-mesenchymal transition markers. MiR-140-5p was found to be able to bind directly to CASC19 and CEMIP. Overexpression of miR-140-5p reversed the effect of CASC19 on cell proliferation and tumor migration, as well as suppressed CASC19-induced CEMIP expression.

CONCLUSION

CASC19 positively regulates CEMIP expression through targeting miR-140-5p. CASC19 may possess an oncogenic function in CRC progression, highlighting its potential as an essential biomarker in CRC diagnosis and therapy.

CCEPR is a novel clinical biomarker for prognosis and regulates cell proliferation through PCNA in osteosarcoma

CCEPR (cervical carcinoma expressed PCNA regulatory lncRNA) has been found to be upregulated and enhance cell proliferation in human cancers. However, the role of CCEPR in osteosarcoma remains to be discovered. In this study, we found CCEPR expression was elevated in osteosarcoma tissue specimens and cell lines compared with adjacent normal tissue specimens and osteoblast cell line, respectively. Meanwhile, osteosarcoma patients with advanced stage or tumor size greater than 8 cm had higher expression of CCEPR than patients with early stage or tumor size less than or equal to 8 cm, respectively. Survival analysis suggested that osteosarcoma patients with high CCEPR expression had a worse overall survival rate than those with low CCEPR expression. The in vitro study indicated that CCEPR positively regulated proliferating cell nuclear antigen (PCNA) expression in osteosarcoma cells and silencing of CCEPR inhibited osteosarcoma cell proliferation through decreasing PCNA expression. In conclusion, CCEPR is a potential prognostic predictor and functions as oncogenic long non-coding RNA (lncRNA) to regulate cell proliferation via PCNA in osteosarcoma.

lncRNA LINC00460 promoted colorectal cancer cells metastasis via miR-939-5p sponging

Background

lncRNAs are widely involved in multiple malignancies including colorectal cancer (CRC). The expression and function of long intergenic non-protein coding RNA 460 (LINC00460) in CRC remains obscure.

Methods

In the present study, quantitative real-time PCR assays were applied to detect the expression changes of LINC00460 and microRNA-939-5p (miR-939-5p) in CRC tissue specimens and cell lines. Western blot assays were used to measure the changes of LIMK2. Bioinformatics analysis, luciferase assays, and RNA pull-down assays were applied to determine the targeting binding effect between LINC00460 and miR-939-5p as well as LIMK2 and miR-939-5p. Transwell assays were used to evaluate the metastatic ability changes of CRC line HT29 and LOVO cells.

Results

We found that LINC00460 was upregulated and closely correlated to clinicopathological features and poor prognosis of patients with CRC. Functionally, we elucidated that LINC00460 promoted metastasis in CRC cell lines HT29 and LOVO. Further, we showed that LIMK2 was a downstream effector in the LINC00460-induced promotion of metastasis in CRC cells HT29 and LOVO. Through online bioinformatics analysis, LINC00460 and LIMK2 were demonstrated to share similar microRNA response elements for miR-939-5p. Then, LINC00460 and LIMK2 were verified to be the targets of miR-939-5p via a luciferase assay and an RNA pull-down assay. Also, miR-939-5p was showed to suppress metastasis by targeting of LIMK2. Lastly, we revealed that LINC00460 promoted LIMK2-mediated metastasis via miR-939-5p sponging in CRC cells HT29 and LOVO.

Conclusion

The findings of this study showed that LINC00460 works as an oncogene in CRC and promoted CRC cell metastasis via regulation of miR-939-3p/LIMK2 axial. The present study might provide a new target in treating CRC.

Long noncoding RNA GACAT3 promotes glioma progression by sponging miR-135a

The long noncoding RNA (lncRNA) gastric cancer associated transcript 3 (GACAT3) has been reported to play important roles in human tumorigenesis. However, its expression pattern, functions, and underlying mechanism in glioma remain unclear. In the present study, we showed that GACAT3 is upregulated in glioma tissues and cell lines. Through online databases, luciferase reporter assays and RNA immunoprecipitation (RIP) assays, we determined that GACAT3 acts as a competing endogenous RNA (ceRNA) for microRNA (miR)-135a, which was downregulated and performed as a tumor inhibitor in glioma. Further, nicotinamide phosphoribosyl transferase (NAMPT) was confirmed as a target gene of miR-135a by a series of gain- and loss-of-function assays. Overall, the present study was the first to show that GACAT3 regulates the expression of NAMPT to promote glioma progression by sponging miR-135a. These findings provide a promising therapy strategy for glioma.

LncRNA MALAT1 protects cardiomyocytes from isoproterenol-induced apoptosis through sponging miR-558 to enhance ULK1-mediated protective autophagy

Investigating the molecular mechanisms of myocardial infarction (MI) and subsequent heart failure have gained considerable attention worldwide. Long noncoding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) has been previously demonstrated to regulate the proliferation and metastasis of several tumors. However, little is known about the effects of MALAT1 in MI and in regulating the cell date after MI. In our study, first, it was shown that the expression levels of MALAT1 were increased in the MI samples compared with normal tissues using quantitative reverse-transcription polymerase chain reaction. Then, MALAT1 knockdown could significantly decrease the cell viability and increase the apoptotic rates in isoproterenol (ISO)-treated H9C2 cells. In addition, we screened the possible target and found that miR-558 is its direct target using dual luciferase reporter assay, indicating that MALAT1 functioned as decoys sponging miR-558. Transfection of miR-558 mimic decreased the cell viability and enhanced the apoptosis. Furthermore, we revealed that miR-558 could downregulate ULK1 expression and suppressed ISO-induced protective autophagy. Activation of MALAT1/miR-558/ULK1 pathway protected H9C2 cells from ISO-induced mitochondria-dependent apoptosis. Finally, we used MALAT1-knockout mice to further demonstrated that MALAT1 protected cardiomyocytes from apoptosis and partially improved the cardiac functions upon ISO treatment. In conclusion, we elucidated that lncRNA MALAT1 protected cardiomyocytes from ISO-induced apoptosis by sponging miR-558 thus promoting ULK1-dependent autophagy. Targeting lncRNA MALAT1 might become a potential strategy in protecting cardiomyocytes during MI.

Long noncoding RNA MALAT1 regulates HDAC4-mediated proliferation and apoptosis via decoying of miR-140-5p in osteosarcoma cells

Noncoding RNAs regulate the initiation and progression of osteosarcoma (OS). The role of long noncoding RNA metastasis‐associated lung adenocarcinoma transcript 1 (MALAT1) playing in OS and whether the function it working out was achieved through HDAC4 pathway remain uncovered. In this study, we illustrated that MALAT1 was upregulated and was correlated with poor prognosis in OS patients. Meanwhile, we demonstrated that a depression of MALAT1 suppressed proliferation and promoted apoptosis in OS cell line HOS and 143B. Further, we verified that MALAT1 exerting its function via upregulating of histone deacetylase 4 (HDAC4). Through an online prediction, a series of luciferase assays and RNA pull‐down assays, we demonstrated that both MALAT1 and HDAC4 were the targets of microRNA‐140‐5p (miR‐140‐5p) via sharing a similar microRNA responding elements. Even further, we revealed that MALAT1 served as a ceRNA of HDAC4 via decoying of miR‐140‐5p. Finally, we proved that MALAT1 promoted OS tumor growth in an in vivo animal study. In summary, the outcomes of this study demonstrated the complex ceRNA network among MALAT, miR‐140‐5p, and HDAC4‐mediated proliferation and apoptosis in OS. This study might provide a new axial in molecular treatment of OS.