Loss of lncRNA-SNHG7 Promotes the Suppression of Hepatic Stellate Cell Activation via miR-378a-3p and DVL2

Uveal melanoma immunogenomics predict immunotherapy resistance and susceptibility

Immune checkpoint inhibition has shown success in treating metastatic cutaneous melanoma but has limited efficacy against metastatic uveal melanoma, a rare variant arising from the immune privileged eye. To better understand this resistance, we comprehensively profile 100 human uveal melanoma metastases using clinicogenomics, transcriptomics, and tumor infiltrating lymphocyte potency assessment. We find that over half of these metastases harbor tumor infiltrating lymphocytes with potent autologous tumor specificity, despite low mutational burden and resistance to prior immunotherapies. However, we observe strikingly low intratumoral T cell receptor clonality within the tumor microenvironment even after prior immunotherapies. To harness these quiescent tumor infiltrating lymphocytes, we develop a transcriptomic biomarker to enable in vivo identification and ex vivo liberation to counter their growth suppression. Finally, we demonstrate that adoptive transfer of these transcriptomically selected tumor infiltrating lymphocytes can promote tumor immunity in patients with metastatic uveal melanoma when other immunotherapies are incapable.

Two sides of the same coin: Non-alcoholic fatty liver disease and atherosclerosis

The prevalence of non-alcoholic fatty liver disease (NAFLD) and atherosclerosis remain high, which is primarily due to widespread adoption of a western diet and sedentary lifestyle. NAFLD, together with advanced forms of this disease such as non-alcoholic steatohepatitis (NASH) and cirrhosis, are closely associated with atherosclerotic-cardiovascular disease (ASCVD). In this review, we discussed the association between NAFLD and atherosclerosis and expounded on the common molecular biomarkers underpinning the pathogenesis of both NAFLD and atherosclerosis. Furthermore, we have summarized the mode of function and potential clinical utility of existing drugs in the context of these diseases.

Abnormal metabolism in hepatic stellate cells: Pandora's box of MAFLD related hepatocellular carcinoma

Metabolic associated fatty liver disease (MAFLD) is a significant risk factor for the development of hepatocellular carcinoma (HCC). Hepatic stellate cells (HSCs), as key mediators in liver injury response, are believed to play a crucial role in the repair process of liver injury. However, in MAFLD patients, the normal metabolic and immunoregulatory mechanisms of HSCs become disrupted, leading to disturbances in the local microenvironment. Abnormally activated HSCs are heavily involved in the initiation and progression of HCC. The metabolic disorders and abnormal activation of HSCs not only initiate liver fibrosis but also contribute to carcinogenesis. In this review, we provide an overview of recent research progress on the relationship between the abnormal metabolism of HSCs and the local immune system in the liver, elucidating the mechanisms of immune imbalance caused by abnormally activated HSCs in MAFLD patients. Based on this understanding, we discuss the potential and challenges of metabolic-based and immunology-based mechanisms in the treatment of MAFLD-related HCC, with a specific focus on the role of HSCs in HCC progression and their potential as targets for anti-cancer therapy. This review aims to enhance researchers' understanding of the importance of HSCs in maintaining normal liver function and highlights the significance of HSCs in the progression of MAFLD-related HCC.

GAS5-inhibited hepatocyte pyroptosis contributes to hepatic stellate cell inactivation via microRNA-684 and AHR

Hepatocyte pyroptosis has been shown to be involved in liver damage progression. Previously, we found that growth arrest-specific 5 (GAS5) is a regulator of hepatic stellate cell (HSC) activation. However, whether GAS5 plays a role in hepatocyte pyroptosis remains unclear. In this study, reduced GAS5 was shown in CCl₄-treated mice and restoration of GAS5-inhibited liver fibrosis in vivo. Hepatocyte pyroptosis participated in the effects of GAS5-inhibited liver fibrosis, associated with reduced caspase-1, NLRP3, and IL-1β (hepatocyte pyroptosis markers). Notably, AHR expression, a suppressor of NLRP3, was enhanced by GAS5. Silencing AHR inhibited GAS5-mediated hepatocyte pyroptosis. GAS5 and AHR were targets of microRNA-684 (miR-684). In addition, the effects of GAS5 on hepatocyte pyroptosis could be inhibited by miR-684. Interestingly, GAS5-mediated hepatocyte pyroptosis contributed to HSC inactivation. In conclusion, we demonstrate that GAS5 inhibits hepatocyte pyroptosis and HSC activation, at least in part, via regulation of miR-684 and AHR.

LncRNA-MIAT activates hepatic stellate cells via regulating Hippo pathway and epithelial-to-mesenchymal transition

Long non-coding RNA-myocardial infarction-associated transcript (lncRNA-MIAT) has been reported to play an important role in the development of multiple cancers. However, the biological roles of MIAT in liver fibrosis are still unknown. In this study, the expression of MIAT is up-regulated during liver fibrosis. Silencing MIAT leads to the suppression of hepatic stellate cell (HSC) proliferation and collagen expression. Double immunofluorescence analysis additionally demonstrates that MIAT inhibition leads to the suppression of type I collagen and α-SMA in vitro. In vivo, MIAT knockdown contributes to the inhibition of fibrosis progression and collagen accumulation. MIAT is confirmed as a target of miR-3085-5p, and the co-location of MIAT and miR-3085-5p is found in HSC cytoplasm. Interestingly, there is a negative correlation between MIAT expression and miR-3085-5p level in cirrhotic patients as well as activated HSCs. In addition, the effects of MIAT inhibition on HSC inactivation are blocked down by miR-3085-5p inhibitor. YAP is a target of miR-3085-5p. Reduced YAP caused by loss of MIAT is reversed by miR-3085-5p inhibitor. Notably, YAP knockdown results in the suppression of MIAT-mediated epithelial-to-mesenchymal transition (EMT) process. In conclusion, we demonstrate that MIAT enhances the activation of HSCs, at least in part, via miR-3085-5p/YAP/EMT signaling pathway.

Long noncoding RNA SNHG7-miRNA-mRNA axes crosstalk with oncogenic signaling pathways in human cancers

LncRNAs and miRNAs are the two most important non-coding RNAs, which have been identified to be associated with cancer progression or prevention. The dysregulation of lncRNAs conducts tumorigenesis and metastasis in different ways. One of the mechanisms is that lncRNAs interact with miRNAs to regulate distinct cellular and genomic processes and cancer progression. LncRNA SNHG7 as an oncogene sponges miRNAs and develops lncRNA-miRNA-mRNA axes, leading to the regulation of several signaling pathways such as Wnt/β-Catenin, PI3K/AKT/mTOR, SIRT1, and Snail-EMT. Therefore, in this article, after a brief overview of lncRNA SNHG7-miRNA-mRNA axes' contribution to cancer development, we will discuss the role of lncRNA SNHG7 in the genes expression and signaling pathways related to cancers development via acting as a ceRNA.

Oncogenic Roles of Small Nucleolar RNA Host Gene 7 (SNHG7) Long Noncoding RNA in Human Cancers and Potentials

Long noncoding RNAs (lncRNAs) are a class of noncoding transcripts characterized with more than 200 nucleotides of length. Unlike their names, some short open reading frames are recognized for them encoding small proteins. LncRNAs are found to play regulatory roles in essential cellular processes such as cell growth and apoptosis. Therefore, an increasing number of lncRNAs are identified with dysregulation in a wide variety of human cancers. SNHG7 is an lncRNA with upregulation in cancer cells and tissues. It is frequently reported with potency of promoting malignant cell behaviors in vitro and in vivo. Like oncogenic/tumor suppressor lncRNAs, SNHG7 is found to exert its tumorigenic functions through interaction with other biological substances. These include sponging target miRNAs (various numbers are identified), regulation of several signaling pathways, transcription factors, and effector proteins. Importantly, clinical studies demonstrate association between high SNHG7 expression and clinicopathological features in cancerous patients, worse prognosis, and enhanced chemoresistance. In this review, we summarize recent studies in three eras of cell, animal, and human experiments to bold the prognostic, diagnostic, and therapeutic potentials.

Prenatal Cadmium Exposure Alters Proliferation in Mouse CD4+ T Cells via LncRNA Snhg7

Objective

Prenatal cadmium (Cd) exposure leads to immunotoxic phenotypes in the offspring affecting coding and non-coding genes. Recent studies have shown that long non-coding RNAs (lncRNAs) are integral to T cell regulation. Here, we investigated the role of long non-coding RNA small nucleolar RNA host gene 7 (lncSnhg7) in T cell proliferation.

Methods

RNA sequencing was used to analyze the expression of lncRNAs in splenic CD4+ T cells with and without CD3/CD28 stimulation. Next, T cells isolated from offspring exposed to control or Cd water throughout mating and gestation were analyzed with and without stimulation with anti-CD3/CD28 beads. Quantitative qPCR and western blotting were used to detect RNA and protein levels of specific genes. Overexpression of a miR-34a mimic was achieved using nucleofection. Apoptosis was measured using flow cytometry and luminescence assays. Flow cytometry was also used to measure T cell proliferation in culture. Finally, lncSnhg7 was knocked down in splenic CD4+ T cells with lentivirus to assess its effect on proliferation.

Results

We identified 23 lncRNAs that were differentially expressed in stimulated versus unstimulated T cells, including lncSnhg7. LncSnhg7 and a downstream protein, GALNT7, are upregulated in T cells from offspring exposed to Cd during gestation. Overexpression of miR-34a, a regulator of lncSnhg7 and GALNT7, suppresses GALNT7 protein levels in primary T cells, but not in a mouse T lymphocyte cell line. The T cells isolated from Cd-exposed offspring exhibit increased proliferation after activation in vitro, but Treg suppression and CD4+ T cell apoptosis are not affected by prenatal Cd exposure. Knockdown on lncSnhg7 inhibits proliferation of CD4+ T cells.

Conclusion

Prenatal Cd exposure alters the expression of lncRNAs during T cell activation. The induction of lncSnhg7 is enhanced in splenic T cells from Cd offspring resulting in the upregulation of GALNT7 protein and increased proliferation following activation. miR-34a overexpression decreased GALNT7 expression and knockdown of lncSnhg7 inhibited proliferation suggesting that the lncSnhg7/miR-34a/GALNT7 is an important pathway in primary CD4+ T cells. These data highlight the need to understand the consequences of environmental exposures on lncRNA functions in non-cancerous cells as well as the effects in utero.

The Roles and Mechanisms of lncRNAs in Liver Fibrosis

Long non-coding RNAs (lncRNAs) can potentially regulate all aspects of cellular activity including differentiation and development, metabolism, proliferation, apoptosis, and activation, and benefited from advances in transcriptomic and genomic research techniques and database management technologies, its functions and mechanisms in physiological and pathological states have been widely reported. Liver fibrosis is typically characterized by a reversible wound healing response, often accompanied by an excessive accumulation of extracellular matrix. In recent years, a range of lncRNAs have been investigated and found to be involved in several cellular-level regulatory processes as competing endogenous RNAs (ceRNAs) that play an important role in the development of liver fibrosis. A variety of lncRNAs have also been shown to contribute to the altered cell cycle, proliferation profile associated with the accelerated development of liver fibrosis. This review aims to discuss the functions and mechanisms of lncRNAs in the development and regression of liver fibrosis, to explore the major lncRNAs involved in the signaling pathways regulating liver fibrosis, to elucidate the mechanisms mediated by lncRNA dysregulation and to provide new diagnostic and therapeutic strategies for liver fibrosis.

Noncoding RNAs Interactions in Hepatic Stellate Cells during Hepatic Fibrosis

Hepatic fibrosis is a reversible wound healing process following liver injury. Although this process is necessary for maintaining liver integrity, severe excessive extracellular matrix accumulation (ECM) could lead to permanent scar formation and destroy the liver structure. The activation of hepatic stellate cells (HSCs) is a key event in hepatic fibrosis. Previous studies show that most antifibrotic therapies focus on the apoptosis of HSCs and the prevention of HSC activation. Noncoding RNAs (ncRNAs) play a substantial role in HSC activation and are likely to be biomarkers or therapeutic targets for the treatment of hepatic fibrosis. This review summarizes and discusses the previously reported ncRNAs, including the microRNAs, long noncoding RNAs, and circular RNAs, highlighting their regulatory roles and interactions in the signaling pathways that regulate HSC activation in hepatic fibrosis.

Lnc-PFAR facilitates autophagy and exacerbates pancreatic fibrosis by reducing pre-miR-141 maturation in chronic pancreatitis

Chronic pancreatitis (CP) is described as progressive inflammatory fibrosis of pancreas, accompanied with irreversible impaired endocrine and exocrine insufficiency. Pancreatic stellate cells (PSCs) are widely distributed in the stroma of the pancreas and PSCs activation has been shown as one of the leading causes for pancreatic fibrosis. Our previous study has revealed that autophagy is dramatically activated in CP tissues, which facilitates PSCs activation and pancreatic fibrosis. Long non-coding RNAs (LncRNAs) have been recognized as crucial regulators for fibrosis-related diseases. LncRNAs interact with RNA binding protein or construct competitive endogenous RNA (ceRNA) hypothesis which elicited the fibrotic processes. Until now, the effects of lncRNAs on PSCs activation and pancreatic fibrosis have not been clearly explored. In this study, a novel lncRNA named Lnc-PFAR was found highly expressed in mouse and human CP tissues. Our data revealed that Lnc-PFAR facilitates PSCs activation and pancreatic fibrosis via RB1CC1-induced autophagy. Lnc-PFAR reduces miR-141 expression by suppressing pre-miR-141 maturation, which eventually upregulates the RB1CC1 and fibrosis-related indicators expression. Meanwhile, Lnc-PFAR enhanced PSCs activation and pancreatic fibrosis through trigging autophagy. Our study interrogates a novel lncRNA-induced mechanism in promoting the development of pancreatic fibrosis, and Lnc-PFAR is suggested to be a prospective therapeutic target in clinical scenarios.

Long non-coding RNAs in metabolic disorders: pathogenetic relevance and potential biomarkers and therapeutic targets

BACKGROUND

It has been suggested that dysregulation of long non-coding RNAs (lncRNAs) could be associated with the incidence and development of metabolic disorders.

AIM

Accordingly, this narrative review described the molecular mechanisms of lncRNAs in the development of metabolic diseases including insulin resistance, diabetes, obesity, non-alcoholic fatty liver disease (NAFLD), cirrhosis, and coronary artery diseases (CAD). Furthermore, we investigated the up-to-date findings on the association of deregulated lncRNAs in the metabolic disorders, and potential use of lncRNAs as biomarkers and therapeutic targets.

CONCLUSION

LncRNAs/miRNA/regulatory proteins axis plays a crucial role in progression of metabolic disorders and may be used in development of therapeutic and diagnostic approaches.

DDX56 modulates post-transcriptional Wnt signaling through miRNAs and is associated with early recurrence in squamous cell lung carcinoma

BACKGROUND

Early recurrence is a major obstacle to prolonged postoperative survival in squamous cell lung carcinoma (SqCLC). The molecular mechanisms underlying early SqCLC recurrence remain unclear, and effective prognostic biomarkers for predicting early recurrence are needed.

METHODS

We analyzed primary tumor samples of 20 SqCLC patients using quantitative proteomics to identify differentially-expressed proteins in patients who experienced early versus late disease recurrence. The expression and prognostic significance of DDX56 was evaluated using a SqCLC tumor tissue microarray and further verified using different online databases. We performed in vitro and in vivo experiments to obtain detailed molecular insight into the functional role of DDX56 in SqCLC.

RESULTS

We found that DDX56 exhibited increased expression in tumors of patients who experienced early versus late disease recurrence. Increased DDX56 expression in SqCLC tumors was subsequently confirmed as an independent prognostic factor of poor recurrence-free survival in independent SqCLC cohorts. Functionally, DDX56 promotes SqCLC cell growth and migration in vitro, and xenograft tumor progression in vivo. Mechanistically, DDX56 post-transcriptionally promotes expression of multiple Wnt signaling pathway-related genes, including CTNNB1, WNT2B, and represses a subset of miRNAs, including miR-378a-3p, a known suppressor of Wnt signaling. Detailed analysis revealed that DDX56 facilitated degradation of primary miR-378a, leading to down-regulation of mature miR-378a-3p and thus derepression of the target gene WNT2B.

CONCLUSION

We identified DDX56 as a novel independent prognostic biomarker that exerts its oncogenic effects through miRNA-mediated post-transcriptional regulation of Wnt signaling genes to promote early SqCLC recurrence. DDX56 may assist in identifying SqCLC patients at increased risk of early recurrence and who could benefit from Wnt signaling-targeted therapies.

MIRLET7BHG promotes hepatocellular carcinoma progression by activating hepatic stellate cells through exosomal SMO to trigger Hedgehog pathway

Hepatocellular carcinoma (HCC), commonly caused by liver fibrosis, is a global challenge with high morbidity. Activation of hepatic stellate cells (HSCs) contributes to hepatic fibrosis. Exosomes are small vesicles that play a significant role in cell-to-cell communication. Smoothened (SMO) is the key signal transducer for Hedgehog pathway. This study was designed to study the function and underlying mechanism of SMO in HSC activation. Functional assays including 5-Ethynyl-2´-deoxyuridine, colony formation, wound healing, transwell, and sphere formation assays disclosed the function of SMO. Western blot analysis of exosome biomarkers, immunofluorescence staining assay, electron microscope, and flow cytometry revealed the existence of exosomes. Bioinformatics analyses and mechanistic assays uncovered the interplays between RNAs. Nude mice xenograft model was established to evaluate HCC tumor growth. We uncovered that SMO was an oncogene in HCC cells and was low-expressed in quiescent HSCs. Then, SMO was upregulated in HSCs cultured with HCC cells-conditioned medium. Next, it was revealed that HCC cells-derived exosomes activated HSCs by transmitting SMO to HSCs. Subsequently, we recognized that microRNA let-7b host gene (MIRLET7BHG) served as the competing endogenous RNA against miR-330-5p to upregulate SMO. In turn, SMO induced hedgehog pathway to promote GLI family zinc finger 1 (Gli1), leading to transcriptional activation of MIRLET7BHG in activated HSCs. In summary, this study demonstrated that Gli1-induced MIRLET7BHG facilitated HCC by activating HSCs through exosomal SMO to stimulate hedgehog pathway, providing a new road for HCC treatment.

Regulatory long non-coding RNAs of hepatic stellate cells in liver fibrosis (Review)

Liver fibrosis (LF) is a continuous wound healing process caused by numerous chronic hepatic diseases and poses a major threat to human health. Activation of hepatic stellate cells (HSCs) is a critical event in the development of hepatic fibrosis. Long non-coding RNAs (lncRNAs) that are involved in HSC activation, participate in the development of LF and are likely to be therapeutic targets for LF. In the present review, the cellular signaling pathways of LF with respect to HSCs were discussed. In particular, this present review highlighted the current knowledge on the role of lncRNAs in activating or inhibiting LF, revealing lncRNAs that are likely to be biomarkers or therapeutic targets for LF. Additional studies should be performed to elucidate the potential of lncRNAs in the diagnosis and prognosis of LF and to provide novel therapeutic approaches for the reversion of LF.

Role of long non‑coding RNAs and related epigenetic mechanisms in liver fibrosis (Review)

Liver fibrosis is one of the major liver pathologies affecting patients worldwide. It results from an improper tissue repair process following liver injury or inflammation. If left untreated, it ultimately leads to liver cirrhosis and liver failure. Long non‑coding RNAs (lncRNAs) have been implicated in a wide variety of diseases. They can regulate gene expression and modulate signaling. Some of the lncRNAs promote, while others inhibit liver fibrosis. Similarly, other epigenetic processes, such as methylation and acetylation regulate gene transcription and can modulate gene expression. Notably, there are several regulatory associations of lncRNAs with other epigenetic processes. A major mechanism of action of long non‑coding RNAs is to competitively bind to their target microRNAs (miRNAs or miRs), which in turn affects miRNA availability and bioactivity. In the present review, the role of lncRNAs and related epigenetic processes contributing to liver fibrosis is discussed. Finally, various potential therapeutic approaches targeting lncRNAs and related epigenetic processes, which are being considered as possible future treatment targets for liver fibrosis are identified.

LncRNA HOXB-AS3 promotes growth, invasion and migration of epithelial ovarian cancer by altering glycolysis

HEADING AIMS

LncRNA HOXB-AS3 is proved as an oncogene in tumors. Herein, we determine the function and mechanism of HOXB-AS3 in epithelial ovarian cancer (EOC) cells.

MATERIALS AND METHODS

Chi-square test, Kaplan-Meier (KM) analysis and Cox regression analysis were used to analyze the clinicopathological features of HOXB-AS3 in EOC patients. CCK8, transwell and wound healing assay were used to test the function of HOXB-AS3. Luciferase reporter assay, western blot and glycolysis rate assay were used for further mechanistic studies.

KEY FINDINGS

HOXB-AS3 was abundantly expressed in EOC tissues, and higher levels of HOXB-AS3 in EOC patients were significantly associated with disease status and overall survival status. EOC patients with high levels of HOXB-AS3 had strikingly shorter disease-free survival (DFS) and overall survival (OS) times than those with low levels. HOXB-AS3 also might as an independent prognostic factor. Further study revealed knockdown of HOXB-AS3 significantly inhibited the proliferation, invasion and migration of EOC cells. Mechanistic investigations suggested that knockdown of HOXB-AS3 could decrease lactate dehydrogenase A (LDHA) expression and the extracellular acidification rate (ECAR) by sponging miR-378a-3p.

SIGNIFICANCE

To our knowledge, this is the first study to suggest that HOXB-AS3 could crosstalk with miRNA in the cytoplasm and alter glycolysis in cancer cells. Our results improve our understanding of the mechanism of HOXB-AS3 and suggest that HOXB-AS3 can act as a predictor of OS and a target for EOC therapies.

Overexpression of Nuclear Enriched Autosomal Transcript 1 Facilitates Cell Proliferation, Migration Invasion, and Suppresses Apoptosis in Endometrial Cancer by Targeting MicroRNA-202-3p/T Cell Immunoglobulin and Mucin Domain 4 Axis

Background: Endometrial cancer (EC) is an intractable gynecological cancer with increasing incidence and mortality worldwide. Accumulating studies indicated that long noncoding RNA nuclear enriched autosomal transcript 1 (NEAT1) was a novel oncogene implicated in a variety of cancers. However, whether NEAT1 could accelerate cell growth in EC is unclear. Methods: NEAT1, microRNA (miR)-202-3p, and T cell immunoglobulin and mucin domain 4 (TIMD4) levels were detected by quantitative real-time polymerase chain reaction. Cell proliferation and apoptosis were examined by cell counting kit-8 and flow cytometry. Transwell assay was employed for the evaluation of cell migration and invasion. The relationship between miR-202-3p and NEAT1 or TIMD4 was determined by luciferase reporter system. TIMD4 protein expression was assessed by Western blot assay. Results: NEAT1 was upregulated, whereas miR-202-3p was downregulated in EC tumors and cells. Depletion of NEAT1 restrained EC cell proliferation, migration, invasion, and improved apoptosis. MiR-202-3p was targeted by NEAT1 and could bind to TIMD4. Subsequently, it is observed that miR-202-3p inhibitor neutralized NEAT1 silencing mediated suppression on EC cell progression. Meanwhile, TIMD4 rescued miR-202-3p induced inhibition on cell progression in EC. Furthermore, it was obvious that NEAT1 facilitated TIMD4 expression by absorbing miR-202-3p in EC. Conclusions: Upregulation of NEAT1 accelerated EC cell progression through sponging miR-202-3p to facilitate TIMD4 expression, providing potential novel treatment method for EC.

MicroRNA-708 modulates Hepatic Stellate Cells activation and enhances extracellular matrix accumulation via direct targeting TMEM88

Transmembrane protein 88 (TMEM88) is a potential 2-transmembrane-type protein that interacts with the PDZ domain of Dishevelled-1 (DVL-1), a crucial component of Wnt signalling pathway through its C-terminal Val-Trp-Val (VWV) motif in Xenopus embryo cells. Since the significant function of β-catenin in liver fibrosis, it is urgent to study the TMEM88 mechanism in liver fibrosis. The current research was for evaluating the function of TMEM88 in the process of the liver fibrosis and clarifying the inherent mechanism. The study found that TMEM88 is decreased in human fibrotic liver tissues. Functionally, TMEM88 significantly reduced the expression levels of α-smooth muscle actin (α-SMA) and collagen type I (Col.I) and repressed extracellular matrix (ECM) accumulation by restoring the balance between matrix metalloproteinases (MMPs) and TIMPs (tissue inhibitor of metalloproteinases). TMEM88 inhibited HSCs proliferation and evaluated the apoptosis of activated LX-2 cells by regulating Wnt3a, Wnt2b and β-catenin of Wnt/β-catenin signalling pathway. Moreover, we demonstrated that miR-708 particularly targeted TMEM88 3'-UTR regions and down-regulated the expression level of TMEM88 in TGF-β1-stimulated LX-2 cells. MiR-708 promoted the generation of ECM and cell activation in activated LX-2 cells. These results determined that miR-708 could promote HSCs activation and enhance ECM accumulation via direct targeting TMEM88 by Wnt/β-catenin signalling pathway. This will provide a potential target for future research in the process of liver fibrosis.

Long non-coding RNA SNHG7 inhibits NLRP3-dependent pyroptosis by targeting the miR-34a/SIRT1 axis in liver cancer

Long non-coding RNA small nucleolar RNA host gene 7 (SNHG7) is involved in a variety of different types of cancer; however, the role of SNHG7 during liver cancer progression is not completely understood. The aim of the present study was to investigate the functional role and regulatory mechanism underlying SNHG7 during liver cancer. A total of 25 paired hepatocellular carcinoma (HCC) tumor tissues and adjacent normal tissues were collected. Reverse transcription-quantitative PCR and western blotting were performed to detect the expression levels of SNHG7, microRNA (miR)-34a, sirtuin 1 (SIRT1) and pyroptosis-related targets. RNA fluorescence in situ hybridization was performed to detect the expression of SNHG7 in HCC tissues. SNHG7 expression was upregulated in HCC tissues and liver cancer cells compared with normal tissues and normal liver cell lines. High expression of SNHG7 inhibited NLR family pyrin domain containing 3 (NLRP3)-dependent pyroptosis in HepG2 and SK-hep-1 cells. Bioinformatics analysis and dual-luciferase reporter assays were performed to investigate the interactions between miR-34a and SNHG7 or SIRT1. SNHG7 served as a competing endogenous RNA of miR-34a, and SIRT1 was identified as a direct target of miR-34a. Cell pyroptosis was evaluated by TUNEL and lactate dehydrogenase release assays. SNHG7 knockdown reduced SIRT1 expression, but increased the expression levels of NLRP3, caspase-1 and interleukin-1β, leading to pyroptosis. SNHG7 knockdown-induced effects were enhanced by miR-34a upregulation. In summary, the present study indicated that the SNHG7/miR-34a/SIRT1 axis contributed to NLRP3-dependent pyroptosis during liver cancer.

The Roles and Mechanisms of lncRNAs in Liver Fibrosis

Many studies have revealed that circulating long noncoding RNAs (lncRNAs) regulate gene and protein expression in the process of hepatic fibrosis. Liver fibrosis is a reversible wound healing response followed by excessive extracellular matrix accumulation. In the development of liver fibrosis, some lncRNAs regulate diverse cellular processes by acting as competing endogenous RNAs (ceRNAs) and binding proteins. Previous investigations demonstrated that overexpression of lncRNAs such as H19, maternally expressed gene 3 (MEG3), growth arrest-specific transcript 5 (GAS5), Gm5091, NR_002155.1, and HIF 1alpha-antisense RNA 1 (HIF1A-AS1) can inhibit the progression of liver fibrosis. Furthermore, the upregulation of several lncRNAs [e.g., nuclear paraspeckle assembly transcript 1 (NEAT1), hox transcript antisense RNA (Hotair), and liver-enriched fibrosis-associated lncRNA1 (lnc-LFAR1)] has been reported to promote liver fibrosis. This review will focus on the functions and mechanisms of lncRNAs, the lncRNA transcriptome profile of liver fibrosis, and the main lncRNAs involved in the signalling pathways that regulate hepatic fibrosis. This review provides insight into the screening of therapeutic and diagnostic markers of liver fibrosis.

Silencing lncRNA Lfar1 alleviates the classical activation and pyoptosis of macrophage in hepatic fibrosis

Hepatic fibrosis is a common pathological consequence of a sustained wound healing response to continuous liver injury, characterized by increased production and accumulation of extracellular matrix. If unresolved, the fibrotic process results in organ failure, and eventually death after the development of cirrhosis. It has been suggested that macrophages play central role in the progression of hepatic fibrosis, which is related to inflammation and pyroptosis, a novel programmed and proinflammatory cell death. However, it remains far less clear if, or how, lncRNAs regulates the activation and pyroptosis of macrophage in hepatic fibrosis. In the present study, we demonstrated that the liver-enriched lncRNA Lfar1, which has been reported to promote hepatic fibrosis through inducing hepatic stellate cells activation and hepatocytes apoptosis, was dysregulated during proinflammatory M1 activation and pyroptosis of macrophage. Our study revealed that silencing lnc-Lfar1 by a lentivirus-shRNA alleviated CCl₄- and BDL-induced proinflammatory M1 macrophage activation and NLRP3 inflammasome-mediated pyroptosis. Furthermore, the in vitro experiments demonstrated that lnc-Lfar1 knockdown significantly suppressed LPS- and IFN-γ-induced proinflammatory activation of macrophages, and inhibited LPS/ATP- and LPS/Nigericin-induced NLRP3 inflammasome-mediated pyroptosis. Mechanistically, lnc-Lfar1 regulated LPS- and IFN-γ-induced proinflammatory activation of macrophages through the NF-ĸB pathway. All these data supported our conclusion that lnc-Lfar1 plays a vital role in controlling the activation and pyroptosis of macrophage, thus providing a possible therapeutic target against inflammation-related disorders including hepatic fibrosis.

Long noncoding RNA SNHG7 contributes to cell proliferation, migration, invasion and epithelial to mesenchymal transition in non-small cell lung cancer by regulating miR-449a/TGIF2 axis

Background

Non‐small cell lung cancer (NSCLC) is an intractable malignant lung cancer with high rates of metastasis and mortality. Currently, long noncoding RNA nuclear RNA host gene 7 (SNHG7) is recognized as a biomarker of multiple cancers. However, the role of SNHG7 in NSCLC requires further understanding.

Methods

The expression of SNHG7, miR‐449a and TGIF2 in NSCLC tumors and cells was examined by quantitative real time polymerase chain reaction (qRT‐PCR). Cell viability was measured by MTT assay. Cell migration and invasion was conducted using transwell assay. Protein expression of TGIF2, vimentin, N‐cadherin and E‐cadherin was detected by western blot. The interaction between miR‐449a and SNHG7 or TGIF2 was determined by luciferase reporter system, RIP and RNA pull‐down assay, respectively. Xenograft mice models were established by subcutaneously injecting A549 cells transfected with sh‐SNHG7 and sh‐control.

Results

SNHG7 expression was upregulated in NSCLC tumors and cells compared with normal tissues and cells. SNHG7 silencing repressed cell proliferation, migration, invasion and epithelial to mesenchymal transition (EMT) in NSCLC. Consistently, SNHG7 knockdown hindered tumor growth in vivo. The subsequent luciferase reporter system, RIP and RNA pull‐down assay validated the interaction between miR‐449a and SNHG7 or TGIF2. The rescue experiments displayed that miR‐449a inhibitor counteracted SNHG7 silencing induced inhibition on proliferation, migration, invasion and EMT. Similarly, restoration of TGIF2 reversed miR‐449a mediated inhibition on cell progression. In addition, the results indicated that SNHG7 could regulate cell progression by targeting miR‐449a/TGIF2 axis.

Conclusion

SNHG7 contributed to cell proliferation, migration, invasion and EMT in NSCLC by upregulating TGIF2 via sponging miR‐449a, representing a novel targeted therapy method for NSCLC.