Identification of novel long non-coding RNAs deregulated in hepatocellular carcinoma using RNA-sequencing

Correlations of Long Noncoding RNA HNF4A-AS1 Alternative Transcripts with Liver Diseases and Drug Metabolism

Hepatocyte nuclear factor 4 alpha antisense 1 (HNF4A-AS1) is a long noncoding RNA (lncRNA) gene physically located next to the transcription factor HNF4A gene in the human genome. Its transcription products have been reported to inhibit the progression of hepatocellular carcinoma (HCC) and negatively regulate the expression of cytochrome P450s (CYPs), including CYP1A2, 2B6, 2C9, 2C19, 2E1, and 3A4. By altering CYP expression, lncRNA HNF4A-AS1 also contributes to the susceptibility of drug-induced liver injury. Thus, HNF4A-AS1 lncRNA is a promising target for controlling HCC and modulating drug metabolism. However, HNF4A-AS1 has four annotated alternative transcripts in the human genome browsers, and it is unclear which transcripts the small interfering RNAs or small hairpin RNAs used in the previous studies are silenced and which transcripts should be used as the target. In this study, four annotated and two newly identified transcripts were confirmed. These six transcripts showed different expression levels in different liver disease conditions, including metabolic dysfunction-associated steatotic liver disease, alcohol-associated liver disease, and obesity. The expression patterns of all HNF4A-AS1 transcripts were further investigated in liver cell growth from human embryonic stem cells to matured hepatocyte-like cells, HepaRG differentiation, and exposure to rifampicin treatment. Several HNF4A-AS1 transcripts highly displayed correlations with these situations. In addition, some of the HNF4A-AS1 transcripts also showed a strong correlation with CYP3A4 during HepaRG maturation and rifampicin exposure. Our findings provide valuable insights into the specific roles of HNF4A-AS1 transcripts, paving the way for more targeted therapeutic strategies for liver diseases and drug metabolism. SIGNIFICANCE STATEMENT: This study explores the alternative transcripts of HNF4A-AS1, showing how their expression changes in different biological conditions, from various liver diseases to the growth and differentiation of hepatocytes and drug metabolism. The generated knowledge is essential for understanding the independent roles of different transcripts from the same lncRNA in different liver diseases and drug metabolism situations.

Transcription factor ZEB1 coordinating with NuRD complex to promote oncogenesis through glycolysis in colorectal cancer

Background

Colorectal cancer (CRC) is an aggressive primary intestinal malignancy with the third-highest incidence and second-highest mortality among all cancer types worldwide. Transcription factors (TFs) regulate cell development and differentiation owing to their ability to recognize specific DNA sequences upstream of genes. Numerous studies have demonstrated a strong correlation between TFs, the etiology of tumors, and therapeutic approaches. Here, we aimed to explore prognosis-related TFs and comprehend their carcinogenic mechanisms, thereby offering novel insights into the diagnosis and management of CRC.

Materials and Methods

Differentially expressed TFs between CRC and normal tissues were identified leveraging The Cancer Genome Atlas database, Weighted correlation network analysis and Cox regression analysis were performed to identify prognosis-related TFs. The cellular functions of hub TF zinc finger E-box binding homeobox 1 (ZEB1) were determined using by 5-ethynyl-2'-deoxyuridine and cell invasion assays in CRC cells. RNA-sequencing, Kyoto Encyclopedia of Genes and Genomes enrichment, and gene set enrichment analyses were used to identify the cellular processes in which ZEB1 participates. Immunoaffinity purification, silver staining mass spectrometry, and a chromatin immunoprecipitation assay were conducted to search for proteins that might interact with ZEB1 and the target genes they jointly regulate.

Results

Thirteen central TFs related to prognosis were identified through bioinformatics analysis techniques. Among these TFs, ZEB1 emerged as the TF most closely associated with CRC, as determined through a combination of regulatory network diagrams, survival curves, and phenotype analyses. ZEB1 promotes CRC cell growth by recruiting the NuRD(MTA1) complex, and the ZEB1/NuRD(MTA1) complex transcriptionally represses glycolysis-associated tumor suppressor genes.

Conclusion

Our study not only identified a hub biomarker related to CRC prognosis but also revealed the specific molecular mechanisms through which ZEB1 affects cancer progression. These insights provide crucial evidence for the diagnosis of CRC and potential treatment opportunities.

Identification of candidate biomarkers for GBM based on WGCNA

Glioblastoma multiforme (GBM), the most aggressive form of primary brain tumor, poses a considerable challenge in neuro-oncology. Despite advancements in therapeutic approaches, the prognosis for GBM patients remains bleak, primarily attributed to its inherent resistance to conventional treatments and a high recurrence rate. The primary goal of this study was to acquire molecular insights into GBM by constructing a gene co-expression network, aiming to identify and predict key genes and signaling pathways associated with this challenging condition. To investigate differentially expressed genes between various grades of Glioblastoma (GBM), we employed Weighted Gene Co-expression Network Analysis (WGCNA) methodology. Through this approach, we were able to identify modules with specific expression patterns in GBM. Next, genes from these modules were performed Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis using ClusterProfiler package. Our findings revealed a negative correlation between biological processes associated with neuronal development and functioning and GBM. Conversely, the processes related to the cell cycle, glomerular development, and ECM-receptor interaction exhibited a positive correlation with GBM. Subsequently, hub genes, including SYP, TYROBP, and ANXA5, were identified. This study offers a comprehensive overview of the existing research landscape on GBM, underscoring the challenges encountered by clinicians and researchers in devising effective therapeutic strategies.

A comprehensive review of lncRNA CRNDE in cancer progression and pathology, with a specific glance at the epithelial-mesenchymal transition (EMT) process

It has been suggested that the long non-coding RNAs (lncRNAs), such as colorectal neoplasia differentially expressed (CRNDE), may contribute to the formation of human cancer. It is yet unknown, though, what therapeutic significance CRNDE expression has for different forms of cancer. CRNDE has recently been proposed as a possible diagnostic biomarker and prognostic pred for excellent specificity and sensitivity in cancer tissues and plasma. To provide the groundwork for potential future therapeutic uses of CRNDE, we briefly overview its biological action and related cancer-related pathways. Next, we mainly address the impact of CRNDE on the epithelial-mesenchymal transition (EMT). The epithelial-mesenchymal transition, or EMT, is an essential biological mechanism involved in the spread of cancer.

Multifaceted TGF-β signaling, a master regulator: From bench-to-bedside, intricacies, and complexities

Physiological embryogenesis and adult tissue homeostasis are regulated by transforming growth factor-β (TGF-β), an evolutionarily conserved family of secreted polypeptide factors, acting in an autocrine and paracrine manner. The role of TGF-β in inflammation, fibrosis, and cancer is complex and sometimes even contradictory, exhibiting either inhibitory or promoting effects depending on the stage of the disease. Under pathological conditions, especially fibrosis and cancer, overexpressed TGF-β causes extracellular matrix deposition, epithelial-mesenchymal transition, cancer-associated fibroblast formation, and/or angiogenesis. In this review article, we have tried to dive deep into the mechanism of action of TGF-β in inflammation, fibrosis, and carcinogenesis. As TGF-β and its downstream signaling mechanism are implicated in fibrosis and carcinogenesis blocking this signaling mechanism appears to be a promising avenue. However, targeting TGF-β carries substantial risk as this pathway is implicated in multiple homeostatic processes and is also known to have tumor-suppressor functions. There is a need for careful dosing of TGF-β drugs for therapeutic use and patient selection.

HNF4α isoforms: the fraternal twin master regulators of liver function

In the more than 30 years since the purification and cloning of Hepatocyte Nuclear Factor 4 (HNF4α), considerable insight into its role in liver function has been gleaned from its target genes and mouse experiments. HNF4α plays a key role in lipid and glucose metabolism and intersects with not just diabetes and circadian rhythms but also with liver cancer, although much remains to be elucidated about those interactions. Similarly, while we are beginning to elucidate the role of the isoforms expressed from its two promoters, we know little about the alternatively spliced variants in other portions of the protein and their impact on the 1000-plus HNF4α target genes. This review will address how HNF4α came to be called the master regulator of liver-specific gene expression with a focus on its role in basic metabolism, the contributions of the various isoforms and the intriguing intersection with the circadian clock.

Normalization of hepatic ChREBP activity does not protect against liver disease progression in a mouse model for Glycogen Storage Disease type Ia

BACKGROUND

Glycogen storage disease type 1a (GSD Ia) is an inborn error of metabolism caused by a defect in glucose-6-phosphatase (G6PC1) activity, which induces severe hepatomegaly and increases the risk for liver cancer. Hepatic GSD Ia is characterized by constitutive activation of Carbohydrate Response Element Binding Protein (ChREBP), a glucose-sensitive transcription factor. Previously, we showed that ChREBP activation limits non-alcoholic fatty liver disease (NAFLD) in hepatic GSD Ia. As ChREBP has been proposed as a pro-oncogenic molecular switch that supports tumour progression, we hypothesized that ChREBP normalization protects against liver disease progression in hepatic GSD Ia.

METHODS

Hepatocyte-specific G6pc knockout (L-G6pc-/-) mice were treated with AAV-shChREBP to normalize hepatic ChREBP activity.

RESULTS

Hepatic ChREBP normalization in GSD Ia mice induced dysplastic liver growth, massively increased hepatocyte size, and was associated with increased hepatic inflammation. Furthermore, nuclear levels of the oncoprotein Yes Associated Protein (YAP) were increased and its transcriptional targets were induced in ChREBP-normalized GSD Ia mice. Hepatic ChREBP normalization furthermore induced DNA damage and mitotic activity in GSD Ia mice, while gene signatures of chromosomal instability, the cytosolic DNA-sensing cGAS-STING pathway, senescence, and hepatocyte dedifferentiation emerged.

CONCLUSIONS

In conclusion, our findings indicate that ChREBP activity limits hepatomegaly while decelerating liver disease progression and protecting against chromosomal instability in hepatic GSD Ia. These results disqualify ChREBP as a therapeutic target for treatment of liver disease in GSD Ia. In addition, they underline the importance of establishing the context-specific roles of hepatic ChREBP to define its therapeutic potential to prevent or treat advanced liver disease.

Long Noncoding RNA H19: A Novel Oncogene in Liver Cancer

Liver cancer is the second leading cause of cancer-related death globally, with limited treatment options. Recent studies have demonstrated the critical role of long noncoding RNAs (lncRNAs) in the pathogenesis of liver cancers. Of note, mounting evidence has shown that lncRNA H19, an endogenous noncoding single-stranded RNA, functions as an oncogene in the development and progression of liver cancer, including hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), the two most prevalent primary liver tumors in adults. H19 can affect many critical biological processes, including the cell proliferation, apoptosis, invasion, and metastasis of liver cancer by its function on epigenetic modification, H19/miR-675 axis, miRNAs sponge, drug resistance, and its regulation of downstream pathways. In this review, we will focus on the most relevant molecular mechanisms of action and regulation of H19 in the development and pathophysiology of HCC and CCA. This review aims to provide valuable perspectives and translational applications of H19 as a potential diagnostic marker and therapeutic target for liver cancer disease.

Dynamic expression of H19 and MALAT1 and their correlation with tumor progression biomarkers in a multistage hepatocarcinogenesis model

Hepatocellular carcinoma (HCC) progresses sequentially in a stepwise pattern. Long noncoding RNA (lncRNA) can regulate the complex cascade of hepatocarcinogenesis. Our study aimed to elucidate the expression profile of H19 and MALAT1 during the different stages of hepatocarcinogenesis and the correlation between H19 and MALAT1 with the genes implicated in the carcinogenesis cascade. We employed a chemically induced hepatocarcinogenesis murine model to mimic the successive stages of human HCC development. Using real-time PCR, we analyzed the expression patterns of H19 and MALAT1, as well as the expression of biomarkers implicated in the Epithelial-Mesenchymal transition (EMT). The protein expression of the mesenchymal marker vimentin was also evaluated using immunohistochemistry in the stepwise induced stages. The histopathological evaluation of the liver tissue sections revealed significant changes during the experiment, with HCC developing at the final stage. Throughout the stages, there was a dynamic significant increase in the expression of H19 and MALAT1 compared to the normal control. Nevertheless, there was no significant difference between each stage and the preceding one. The tumor progression biomarkers (Matrix Metalloproteinases, vimentin, and β-catenin) exhibited the same trend of steadily increasing levels. However, in the case of Zinc finger E-box-binding homeobox 1 and 2 (ZEB1 and ZEB2), the significant elevation was only detected at the last stage of induction. The correlation between lncRNAs and the tumor progression biomarkers revealed a strong positive correlation between the expression pattern of H19 and MALAT1 with Matrix Metalloproteinases 2 and 9 and vimentin. Our findings imply that genetic and epigenetic alterations influence HCC development in a stepwise progressive pattern.

Hepatic stellate cell-released CXCL1 aggravates HCC malignant behaviors through the MIR4435-2HG/miR-506-3p/TGFB1 axis

Hepatic stellate cell (HSC) activation is a critical event in the development of hepatic fibrosis and hepatocellular carcinoma (HCC). By the release of soluble cytokines, chemokines, and chemotaxis, HSCs affect HCC cell phenotypes through a complex tumor microenvironment. In this study, weighted gene co-expression network analysis (WGCNA) was used to identify the TGF-β signaling pathway as a key signaling pathway in Hep3B cells cultured in HSC conditioned medium. MIR4435-2HG is a hub lncRNA associated with the TGF-β signaling pathway and HSC activation. HSC-condition medium (CM) culture induced HCC cell malignant behaviors, which were partially reversed by MIR4435-2HG silencing. miR-506-3p directly bound to MIR4435-2HG and the 3'UTR of TGFB1. Similarly, overexpression of miR-506-3p also attenuated HSC-CM-induced malignant behavior of HCC cells. In HSC-CM cultured HCC cells, the effects of MIR4435-2HG knockdown on TGFB1 expression and HCC cell phenotypes were partially reversed by miR-506-3p inhibition. HSCs affected HCC cell phenotypes by releasing CXCL1. In an orthotopic xenotransplanted tumor model of HCC cells plus HSCs in mice, CXCR2 knockdown in HCC cells significantly inhibited tumorigenesis, which was partially reversed by MIR4435-2HG overexpression in HCC cells. In HCC tissue samples, the levels of CXCL1, TGF-β1, and MIR4435-2HG were upregulated, while miR-506-3p expression was downregulated. In conclusion, HSC-released CXCL1 aggravated HCC cell malignant behaviors through the MIR4435-2HG/miR-506-3p/TGFB1 axis. In addition to CXCL1, the MIR4435-2HG/miR-506-3p/TGFB1 axis might also be the underlying target for HCC therapy.

Impact of RNA degradation on next-generation sequencing transcriptome data

RNA sequencing is an innovative technology to study transcriptomes in both biological and clinical research. However, clinical specimens from patients undergoing surgical operations have a major challenge due to sample degradation. This study replicated the process of RNA degradation by maintaining cells at room temperature to achieve none, slight, middle, and high levels of RNA degradation with decreasing RNA integrity numbers (RIN) of approximately 9.8, 6.7, 4.4, and 2.5, respectively. Next, the differential expression of mRNA and long non-coding RNA (lncRNA) was analyzed in the four degradation groups along with pathway enrichment analysis. The results showed that the similarity of lncRNAs exhibited significant differences even for a slight level of RNA degradation compared with the non-degraded RNA sample. Also, the RNA degradation process was found to be universal, global, and random; the differentially expressed genes increased with an increase in degradation but the pathway enrichment phenomenon was not significantly observed.

CRNDE: A valuable long noncoding RNA for diagnosis and therapy of solid and hematological malignancies

Colorectal neoplasia differentially expressed (CRNDE) is an oncogenic long noncoding RNA (lncRNA). Increased CRNDE expression was initially discovered in colorectal cancer and then in a variety of solid tumors and hematological malignancies. CRNDE participates in multiple biological processes, such as cell proliferation, differentiation, migration, and apoptosis. CRNDE has been shown to modulate target gene expression through multiple mechanisms, including transcriptional regulation, post-transcriptional regulation, and competition for microRNA (miRNA) binding. In this review, we summarize the evidence that supports CRNDE in the diagnosis and prognosis predicting of cancers. The functional roles and molecular mechanisms of CRNDE are further described for major types of solid tumors and hematological malignancies. The therapeutic potential of CRNDE as a target for research and development is also discussed.

DNA Methylation Regulates a Set of Long Non-Coding RNAs Compromising Hepatic Identity during Hepatocarcinogenesis

Simple Summary

Hepatocarcinogenesis is a long process which implies the loss of hepatic functions. Our effort is to understand the mechanisms implicated in this pathological process in order to contribute to the development of new diagnostic markers and therapeutic targets. In this study we have identified a set of lncRNAs significantly downregulated in hepatocellular carcinoma (HCC) in correlation with the grade of tumor dedifferentiation and patients’ worse prognosis. Mechanistically, our results show that they are related with hepatic differentiation and at least a subset of those lncRNAs are essential to ensure the expression of other hepato-specific genes required for liver function. Moreover, we demonstrate that the expression of these lncRNAs in HCC is silenced by DNA methylation. All in all, we uncover connected epigenetic alterations involved in the progression of liver cancer and identify potential new biomarkers.

Abstract

Background: Long noncoding RNAs (lncRNAs) are emerging as key players in cancer, including hepatocellular carcinoma (HCC). Here we identify the mechanism implicated in the HCC inhibition of a set of lncRNAs, and their contribution to the process of hepatocarcinogenesis. Methods and Results: The top-ranked 35 lncRNAs downregulated in HCC (Top35 LNDH) were validated in several human HCC cohorts. We demonstrate that their inhibition is associated with promoter hypermethylation in HCC compared to control tissue, and in HCC human cell lines compared to primary hepatocytes. Moreover, demethylating treatment of HCC human cell lines induced the expression of these lncRNAs. The Top35 LNDH were preferentially expressed in the adult healthy liver compared to other tissues and fetal liver and were induced in well-differentiated HepaRG cells. Remarkably, their knockdown compromised the expression of other hepato-specific genes. Finally, the expression of the Top35 LNDH positively correlates with the grade of tumor differentiation and, more importantly, with a better patient prognosis. Conclusions: Our results demonstrate that the selected Top35 LNDH are not only part of the genes that compose the hepatic differentiated signature but participate in its establishment. Moreover, their downregulation through DNA methylation occurs during the process of hepatocarcinogenesis compromising hepatocellular differentiation and HCC patients’ prognosis.

Novel biomarkers of microRNAs in gastric cancer; an overview from diagnosis to treatment

The fourth frequent disease in the world and the second cause of cancer-related death is gastric cancer (GC). In this way, over 80% of diagnoses are made in the middle to advanced degrees of the disease, underscoring the requirement for innovative biomarkers that can be identified quickly. Meaningly, biomarkers that can complement endoscopic diagnosis and be used to detect patients with a high risk of GC are desperately needed. These biomarkers will allow for the accurate prediction of therapy response and prognosis in GC patients, as well as the development of an optimal treatment strategy for each individual. Conspicoiusly, microRNAs (miRNAs) and small noncoding RNA regulates the expression of target mRNA and thereby modifies critical biological mechanisms. According to the data, abnormally miRNAs expression in GC is linked to tumor growth, carcinogenesis, aggression and distant metastasis. Importantly, miRNA expression patterns and next-generation sequencing (NGS) can also be applied to analyze kinds of tissues and cancers. Given the high death rates and poor prognosis of GC, and the absence of a clinical diagnostic factor that is adequately sensitive to GC, research into novel sensitive and specific markers for GC diagnosis is critical. In this review,we evaluate the latest research findings that suggest the feasibility and clinical utility of miRNAs in GC.

The Role of Long Non-Coding RNAs in the Tumor Immune Microenvironment

Tumorigenesis is a complicated process caused by successive genetic and epigenetic alterations. The past decades demonstrated that the immune system affects tumorigenesis, tumor progression, and metastasis. Although increasing immunotherapies are revealed, only a tiny proportion of them are effective. Long non-coding RNAs (lncRNAs) are a class of single-stranded RNA molecules larger than 200 nucleotides and are essential in the molecular network of oncology and immunology. Increasing researches have focused on the connection between lncRNAs and cancer immunotherapy. However, the in-depth mechanisms are still elusive. In this review, we outline the latest studies on the functions of lncRNAs in the tumor immune microenvironment. Via participating in various biological processes such as neutrophil recruitment, macrophage polarization, NK cells cytotoxicity, and T cells functions, lncRNAs regulate tumorigenesis, tumor invasion, epithelial-mesenchymal transition (EMT), and angiogenesis. In addition, we reviewed the current understanding of the relevant strategies for targeting lncRNAs. LncRNAs-based therapeutics may represent promising approaches in serving as prognostic biomarkers or potential therapeutic targets in cancer, providing ideas for future research and clinical application on cancer diagnosis and therapies.

Long non-coding RNA CRNDE as potential biomarkers facilitate inflammation and apoptosis in alcoholic liver disease

Due to persistent inconsistencies in the expression data of alcoholic liver disease (ALD), it is necessary to turn to “pre-laboratory” comprehensive analysis in order to accelerate effective precision medicine and transformation research. We screened pseudogene-derived lncRNA associated with ALD by comparative analysis of 2 independent data sets from GEO. Three lncRNAs (CRNDE, RBMS3-AS3, and LINC01088) were demonstrated to be potentially useful diagnostic markers in ALD. Among them, the expression of CRNDE is up-regulated. Therefore, we focus on CRNDE. Kyoto Encyclopedia of Genes and Genomes pathways analysis revealed higher CRNDE can activate MAPK signaling pathway, apoptosis, wnt signaling pathway, and hematopoietic cell lineage. Next, we established ALD animal model and verified the success of the modeling. The result showed ALD tissues in mice had significantly higher CRNDE levels than normal tissues. Moreover, the increase of IL-6 in the serum of mice in the low-dose group is related to the activation of inflammatory factors after alcohol-induced liver injury. In addition, alcohol can induce apoptosis, and knockdown of CRNDE can reduce apoptosis. Our integrated expression profiling identified CRNDE independently associated with ALD. CRNDE can facilitate inflammation and apoptosis in ALD.

Non-Coding RNAs in Normal B-Cell Development and in Mantle Cell Lymphoma: From Molecular Mechanism to Biomarker and Therapeutic Agent Potential

B-lymphocytes are essential for an efficient immune response against a variety of pathogens. A large fraction of hematologic malignancies are of B-cell origin, suggesting that the development and activation of B cells must be tightly regulated. In recent years, differentially expressed non-coding RNAs have been identified in mantle cell lymphoma (MCL) tumor samples as opposed to their naive, normal B-cell compartment. These aberrantly expressed molecules, specifically microRNAs (miRNAs), circular RNAs (circRNAs) and long non-coding RNAs (lncRNAs), have a role in cellular growth and survival pathways in various biological models. Here, we provide an overview of current knowledge on the role of non-coding RNAs and their relevant targets in B-cell development, activation and malignant transformation, summarizing the current understanding of the role of aberrant expression of non-coding RNAs in MCL pathobiology with perspectives for clinical use.

Long non-coding RNA muskelin 1 antisense RNA (MKLN1-AS) is a potential diagnostic and prognostic biomarker and therapeutic target for hepatocellular carcinoma

BACKGROUNDS/AIMS

Hepatocellular carcinoma is recognized as the most common subtype of hepatic cancer. Muskelin 1 antisense RNA (MKLN1-AS) shows prognostic value in hepatitis B virus-hepatocellular carcinoma. The aim of this study is to investigate the detailed biological role of MKLN1-AS and Yes-associated transcriptional regulator 1 (YAP1)-related mechanisms.

METHODS

Based on online databases (GEPIA, TCGA, and GEO), the expression of MKLN1-AS and YAP1 in patients with hepatocellular carcinoma was analyzed. The IntaRNA algorithm was used to predict complementary sites between MKLN1-AS and YAP1 mRNA. Hepatocellular carcinoma tumor tissues and cells were collected for the quantification of MKLN1-AS and YAP1. FISH was performed to explore the location of MKLN1-AS in cells. The effects of MKLN1-AS and YAP1 on proliferation, migration and invasionof hepatocellular carcinoma were determined in vitro and in vivo. Actinomycin D and RNA immunoprecipitation were resorted to confirm the regulatory role of MKLN1-AS in YAP1 expression.

RESULTS

The up-regulation of MKLN1-AS contributed to the poor prognosis of patients with hepatocellular carcinoma. MKLN1-AS and YAP1 were overexpressed in hepatocellular carcinoma tissues and cells. MKLN1-AS positively modulated YAP1 expression through targeting and stabilizing YAP1 mRNA.MKLN1-AS was predominantly located in the cytoplasm of the cells. MKLN1-AS intensified proliferation, migration and invasion of hepatocellular carcinoma cells via YAP1. MKLN1-AS also caused hepatocarcinogenesis through inducing YAP1 expression in vivo.

CONCLUSIONS

MKLN1-AS overexpression enhances the stability of YAP1 mRNA, which is necessary for the oncogenic activity of MKLN1-AS. MKLN1-AS can be utilized in the diagnosis and prognosis of hepatocellular carcinoma as an upstream factor of YAP1.

The mechanism of lncRNA-CRNDE in regulating tumour-associated macrophage M2 polarization and promoting tumour angiogenesis

M2 macrophages can promote liver cancer metastasis by promoting tumour angiogenesis; however, the mechanism underlying macrophage polarization has not been completely revealed. In this study, we mainly explored the mechanism underlying long non‐coding RNA‐CRNDE (lncRNA‐CRNDE) in regulating M2 macrophage polarization and promoting liver cancer angiogenesis. The expression of CRNDE was up‐regulated or down‐regulated in THP‐1 cells (CRNDE^‐/‐‐THP‐1 cells and pcDNA3.1‐CRNDE‐THP‐1). THP‐1 cells were co‐cultured with liver cancer cell line H22, and M2 polarization was induced in THP‐1 by IL‐4/13 to simulate tumour‐induced macrophage polarization. As a result, after CRNDE overexpression, THP‐1 cell viability was up‐regulated, the expression of M2 membrane marker CD163 was up‐regulated, and the proportion of F4/80 + CD163+ cells was also up‐regulated. ELISA assay showed that the expression of M2 markers (including TGF‐β1 and IL‐10) and chemokines (including CCl22 and CCL22) was up‐regulated, and the expression of key signals (including STAT6, JAK‐1, p‐AKT1, and Arg‐1) was also up‐regulated, which were significantly different compared with the control group (Con). In addition, the intervention effect of CRNDE on THP‐1 was consistent between co‐culture with H22 cells and IL‐4/13 induction assay. The induced M2 THP‐1 cells were co‐cultured with HUVEC. As a result, THP‐1 cells with CRNDE overexpression can promote the migration and angiogenesis of HUVEC cells in vitro and simultaneously up‐regulate the expression of Notch1, Dll4 and VEGFR2, indicating that THP‐1 M2 polarization induced by CRNDE could further promote angiogenesis. The H22 cell tumour‐bearing mouse model was constructed, followed by injection of CRNDE anti‐oligosense nucleotides and overexpression plasmids to interfere CRNDE expression in tumour‐bearing tissues. Consequently, down‐regulation of CRNDE could down‐regulate tumour volume, simultaneously down‐regulate the expression of CD163 and CD31 in tissues, decrease the expression of key proteins (including JAK‐1, STAT‐6, p‐STAT6 and p‐AKT1), and down‐regulate the expression of key angiogenesis‐related proteins (including VEGF, Notch1, Dll4 and VEGFR2). In this study, we found that CENDE could indirectly regulate tumour angiogenesis by promoting M2 polarization of macrophages, which is also one of the mechanisms of microenvironmental immune regulation in liver cancer.

Modulation of the TGF-β signaling pathway by long noncoding RNA in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a type of liver cancer with poor prognosis. There have been demonstrated to exist many possible mechanisms in HCC tumorigenesis, and recent investigations have provided some promising therapy targets. However, further mechanisms remain to be researched to improve the therapeutic strategy and diagnosis of HCC. Transforming growth factor-β (TGF-β) is a pleiotropic cytokine which plays critical roles in networks of different cellular processes, and TGF-β signaling has been found to participate in tumor initiation and development of HCC in recent years. Moreover, among the molecules and signaling pathways, researchers paid more attention to lncRNAs (long non-coding RNAs), but the connection between lncRNAs and TGF-βremain poorly understood. In this review, we conclude the malignant procedure which lncRNAs and TGF-β involved in, and summarize the mechanisms of lncRNAs and TGF-βin HCC initiation and development. Furthermore, the interaction between lncRNA and TGF-β are paid more attention, and the potential therapy targets are mentioned.

Identification of a Novel Cancer Stemness-Associated ceRNA Axis in Lung Adenocarcinoma via Stemness Indices Analysis

The aim of this study was to identify a novel cancer stemness-related ceRNA regulatory axis in lung adenocarcinoma (LUAD) via weighted gene coexpression network analysis of a stemness index. The RNA sequencing expression profiles of 513 cancer samples and 60 normal samples were obtained from the TCGA database. Differentially expressed mRNAs (DEmRNAs), lncRNAs (DElncRNAs), and miRNAs (DEmiRNAs) were identified with R software. Functional enrichment analysis was conducted using DAVID 6.8. The ceRNA network was constructed via multiple bioinformatics analyses, and the correlations between possible ceRNAs and prognosis were analyzed using Kaplan–Meier plots. WGCNA was then applied to distinguish key genes related to the mRNA expression-based stemness index (mRNAsi) in LUAD. After combining the weighted gene coexpression and ceRNA networks, a novel ceRNA regulatory axis was identified, and its biological functions were explored in vitro and vivo. In total, 1,825 DElncRNAs, 291 DEmiRNAs, and 3,742 DEmRNAs were identified. Functional enrichment analysis revealed that the DEmRNAs might be associated with LUAD onset and progression. The ceRNA network was constructed with 14 lncRNAs, 10 miRNAs, and 52 mRNAs. Kaplan–Meier analysis identified 2 DEmiRNAs, 5 DElncRNAs, and 41 DEmRNAs with remarkable prognostic power. One gene (MFAP4) in the ceRNA network was found to be closely related to mRNAsi by using WGCNA. Functional investigation further confirmed that the C8orf34-as1/miR-671-5p/MFAP4 regulatory axis has important functions in LUAD cell migration and stemness. This study provides a deeper understanding of the lncRNA–miRNA–mRNA ceRNA network and, more importantly, reveals a novel ceRNA regulatory axis, which may provide new insights into novel molecular therapeutic targets for inhibiting LUAD stem characteristics.

LINC00885 a Novel Oncogenic Long Non-Coding RNA Associated with Early Stage Breast Cancer Progression

Long intergenic non-protein coding RNA 885 (LINC00885) was identified as significantly upregulated in breast ductal carcinoma in situ (DCIS). The aim of this study was to characterize the phenotypic effects and signaling pathways modulated by LINC00885 in non-invasive and invasive breast cancer models. We determined that LINC00885 induces premalignant phenotypic changes by increasing cell proliferation, motility, migration and altering 3D growth in normal and DCIS breast cell lines. Transcriptomic studies (RNA-seq) identified the main signaling pathways modulated by LINC00885, which include bioprocesses related to TP53 signaling pathway and proliferative signatures such as activation of EREG, EGFR and FOXM1 pathways. LINC00885 silencing in breast cancer lines overexpressing this lncRNA leads to downregulation of proliferation related transcripts such as EREG, CMYC, CCND1 and to significant decrease in cell migration and motility. TCGA-BRCA data analyses show an association between high LINC00885 expression and worse overall survival in patients with primary invasive breast carcinomas (p = 0.024), suggesting that the pro-tumorigenic effects of LINC00885 overexpression persist post-invasion. We conclude that LINC00885 behaves as a positive regulator of cell growth both in normal and DCIS breast cells possibly operating as a ceRNA and representing a novel oncogenic lncRNA associated with early stage breast cancer progression.

Panel of potential lncRNA biomarkers can distinguish various types of liver malignant and benign tumors

PURPOSE

Liver cancers are among the deadliest malignancies due to a limited efficacy of early diagnostics, the lack of appropriate biomarkers and insufficient discrimination of different types of tumors by classic and molecular methods. In this study, we searched for novel long non-coding RNA (lncRNA) as well as validated several known candidates suitable as probable biomarkers for primary liver tumors of various etiology.

METHODS

We described a novel lncRNA HELIS (aka "HEalthy LIver Specific") and estimated its expression by RT-qPCR in 82 paired tissue samples from patients with hepatocellular carcinoma (HCC), cholangiocarcinoma (CCA), combined HCC-CCA, pediatric hepatoblastoma (HBL) and non-malignant hepatocellular adenoma (HCA) and focal nodular hyperplasia (FNH). Additionally, we examined expression of cancer-associated lncRNAs HULC, MALAT1, UCA1, CYTOR, LINC01093 and H19, which were previously studied mainly in HCC.

RESULTS

We demonstrated that down-regulation of HELIS strongly correlates with carcinogenesis; whereas in tumors with non-hepatocyte origin (HBL, CCA) or in a number of poorly differentiated HCC, this lncRNA is not expressed. We showed that recently discovered LINC01093 is dramatically down-regulated in all malignant liver cancers; while in benign tumors LINC01093 expression is just twice decreased in comparison to adjacent samples.

CONCLUSION

Our study revealed that among all measured biomarkers only down-regulated HELIS and LINC01093, up-regulated CYTOR and dysregulated HULC are perspective for differential diagnostics of liver cancers; whereas others demonstrated discordant results and cannot be considered as potential universal biomarkers for this purpose.

Distinct type 2-high inflammation associated molecular signatures of chronic rhinosinusitis with nasal polyps with comorbid asthma

Background

Patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and comorbid asthma have more severe disease and are difficult to treat. However, the molecular endotypes associated with CRSwNP with comorbid asthma (CRSwNP + AS) are not clear. This study aimed to investigate the characteristics of type 2 inflammation and the molecular signatures associated with CRSwNP + AS.

Methods

A total of 195 subjects; including 65 CRSwNP + AS patients, 99 CRSwNP-alone patients, and 31 healthy control subjects; were enrolled in the study. Nasal tissues from patients with CRSwNP + AS, CRSwNP-alone and control subjects were assessed for infiltration of inflammatory cells and concentrations of total IgE. Whole-transcriptome sequencing was performed and differentially expressed (DE) mRNAs and long non-coding RNAs (lncRNAs) and their associated pathways were analyzed. The correlations between type 2 cytokines and local eosinophils, tissue IgE, and transcriptome signatures were evaluated.

Results

Significantly higher local eosinophil infiltration and higher levels of total IgE were found in nasal tissues from CRSwNP + AS patients than in nasal tissues from CRSwNP-alone patients. Furthermore, atopy and recurrence were significantly more frequent in patients with CRSwNP + AS than in patients with CRSwNP-alone (62.5% vs 28.6% and 66.7% vs 26.9%, respectively). RNA sequencing analysis identified 1988 common DE-mRNAs, and 176 common DE-lncRNAs shared by CRSwNP + AS versus control and CRSwNP-alone versus control. Weighted gene coexpression network analysis (WGCNA) identified LINC01146 as hub lncRNA dysregulated in both subtypes of CRSwNP. Overall, 968 DE-mRNAs and 312 DE-lncRNAs were identified between CRSwNP + AS and CRSwNP-alone. Both pathway enrichment analysis and WGCNA indicated that the phenotypic traits of CRSwNP + AS were mainly associated with higher activities of arachidonic acid metabolism, type 2 cytokines related pathway and fibrinolysis pathway, and lower activity of IL-17 signalling pathway. Furthermore, the expression of type 2 cytokines; IL5 and IL13, was positively correlated with local eosinophil infiltration, tissue IgE level, and the expression of DE-mRNAs that related to arachidonic acid metabolism. Moreover, WGCNA identified HK3-006 as hub lncRNA in yellow module that most positively correlated with phenotypic traits of CRSwNP + AS.

Conclusions

Patients with CRSwNP + AS have distinct type 2-high inflammation-associated molecular signatures in nasal tissues compared to patients with CRSwNP-alone.

Identification of Key Biological Processes, Pathways, Networks, and Genes with Potential Prognostic Values in Hepatocellular Carcinoma Using a Bioinformatics Approach

Aim: Hepatocellular carcinoma (HCC), as one primary liver cancer type, accounts for 75%-85% of liver cancer cases. HCC is the second leading cause of cancer death in East Asia and sub-Saharan Africa and the sixth most common in western countries. Identification of key genes would facilitate the development of therapies and improve the prognosis outcomes of HCC patients. This study was to identify the key biological processes, pathways, and key genes in HCC. Methods: Data were downloaded from Broad GDAC. Differentially expressed genes (DEGs) and weighted gene coexpression network (WGCNA) were analyzed by DESeq2 and WGCNA, respectively. Gene ontology (GO) and KEGG enrichment analyses were performed on all DEGs and the coexpressed genes in two significant modules. Kaplan-Meier plotter online database was used to identify the potential prognostic genes in HCC. Finally, GEO database was used to validate the analysis of gene expression of Broad GDAC data. Results: The authors identified the dark gray and red modules as the significant modules in HCC based on WGCNA. GO and KEGG enrichment of the two significant modules identified the mitochondrion-mediated metabolic processes and pathways, and the cell cycle as the key biological processes and pathways in HCC. Subsequently, 28 hub genes were screened out by constructing protein-protein interaction network using Metascape. Finally, three genes (NDUFAF6, CKAP5, and DSN1 genes) were identified to be potential prognostic and key genes in HCC based on Kaplan-Meier survival analysis, GEO dataset validation, and literature review. Conclusions: The authors found that mitochondrion-mediated metabolic processes and the cell cycle were the key biological processes and pathways in HCC. NDUFAF6, CKAP5, and DSN1 genes were valuable genes with the potential to be prognosis biomarkers and targeted therapies in HCC.

The Roles of Long Noncoding RNAs HNF1α-AS1 and HNF4α-AS1 in Drug Metabolism and Human Diseases

Long noncoding RNAs (lncRNAs) are RNAs with a length of over 200 nucleotides that do not have protein-coding abilities. Recent studies suggest that lncRNAs are highly involved in physiological functions and diseases. lncRNAs HNF1α-AS1 and HNF4α-AS1 are transcripts of lncRNA genes HNF1α-AS1 and HNF4α-AS1, which are antisense lncRNA genes located in the neighborhood regions of the transcription factor (TF) genes HNF1α and HNF4α, respectively. HNF1α-AS1 and HNF4α-AS1 have been reported to be involved in several important functions in human physiological activities and diseases. In the liver, HNF1α-AS1 and HNF4α-AS1 regulate the expression and function of several drug-metabolizing cytochrome P450 (P450) enzymes, which also further impact P450-mediated drug metabolism and drug toxicity. In addition, HNF1α-AS1 and HNF4α-AS1 also play important roles in the tumorigenesis, progression, invasion, and treatment outcome of several cancers. Through interacting with different molecules, including miRNAs and proteins, HNF1α-AS1 and HNF4α-AS1 can regulate their target genes in several different mechanisms including miRNA sponge, decoy, or scaffold. The purpose of the current review is to summarize the identified functions and mechanisms of HNF1α-AS1 and HNF4α-AS1 and to discuss the future directions of research of these two lncRNAs.

The Good, the Bad, the Question-H19 in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), the most common primary liver cancer, is challenging to treat due to its typical late diagnosis, mostly at an advanced stage. Therefore, there is a particular need for research in diagnostic and prognostic biomarkers and therapeutic targets for HCC. The use of long noncoding (lnc) RNAs can widen the list of novel molecular targets improving cancer therapy. In hepatocarcinogenesis, the role of the lncRNA H19, which has been known for more than 30 years now, is still controversially discussed. H19 was described to work either as a tumor suppressor in vitro and in vivo, or to have oncogenic features. This review attempts to survey the conflicting study results and tries to elucidate the potential reasons for the contrary findings, i.e., different methods, models, or readout parameters. This review encompasses in vitro and in vivo models as well as studies on human patient samples. Although the function of H19 in HCC remains elusive, a short outlook summarizes some ideas of using the H19 locus as a novel target for liver cancer therapy.

Identification of co-expression modules and potential biomarkers of breast cancer by WGCNA

Breast cancer is a very serious disease that threatens human health. The identification of co-expression modules is conducive to revealing the interaction mechanism between genes. The potential biomarkers identified from the co-expression modules have profound implications for the diagnosis and treatment of breast cancer. According to the clinical staging information, the gene expression data of breast cancer was divided into different stages and analyzed separately. The co-expression modules for each stage were identified by WGCNA. The pathways involved in the co-expression modules of each stage were revealed by KEGG enrichment analysis. Combined with clinical information, 81 core genes were screened from the co-expression modules of each stage. By constructing a support vector machine, it was confirmed that these core genes can effectively distinguish breast cancer samples. The biological functions involved in these core genes are revealed by GO enrichment analysis. Survival analysis showed that the expression of 11 genes had significant effects on the survival of breast cancer patients. These results may provide a reference for the mechanism study of breast cancer.

Identification of novel biomarkers affecting the metastasis of colorectal cancer through bioinformatics analysis and validation through qRT-PCR

Background

Tumor progression and distant metastasis are the main causes of deaths in colorectal cancer (CRC) patients, and the molecular mechanisms in CRC metastasis have not been completely discovered.

Methods

We identified differentially expressed genes (DEGs) and lncRNAs (DELs) of CRC from The Cancer Genome Atlas (TCGA) database. Then we conducted the weighted gene co-expression network analysis (WGCNA) to investigate co-expression modules related with CRC metastasis. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, DEG-DEL co-expression network and survival analyses of significant modules were also conducted. Finally, the expressions of selected biomarkers were validated in cell lines by quantitative real-time PCR (qRT-PCR).

Results

2032 DEGs and 487 DELs were involved the construction of WGCNA network, and greenyellow, turquoise and brown module were identified to have more significant correlation with CRC metastasis. GO and KEGG pathway analysis of these three modules have proven that the functions of DEGs were closely involved in many important processes in cancer pathogenesis. Through the DEG-DEL co-expression network, 12 DEGs and 2 DELs were considered as hub nodes. Besides, survival analysis showed that 30 DEGs were associated with the overall survival of CRC. Then 10 candidate biomarkers were chosen for validation and the expression of CA2, CHP2, SULT1B1, MOGAT2 and C1orf115 were significantly decreased in CRC cell lines when compared to normal human colonic epithelial cells, which were consistent with the results of differential expression analysis. Especially, low expression of SULT1B1, MOGAT2 and C1orf115 were closely correlated with poorer survival of CRC.

Conclusion

This study identified 5 genes as new biomarkers affecting the metastasis of CRC. Besides, SULT1B1, MOGAT2 and C1orf115 might be implicated in the prognosis of CRC patients.

Identifying 4 Novel lncRNAs as Potential Biomarkers for Acute Rejection and Graft Loss of Renal Allograft

Acute rejection (AR) after kidney transplant is one of the major obstacles to obtain ideal graft survival. Reliable molecular biomarkers for AR and renal allograft loss are lacking. This study was performed to identify novel long noncoding RNAs (lncRNAs) for diagnosing AR and predicting the risk of graft loss. The several microarray datasets with AR and nonrejection specimens of renal allograft downloaded from Gene Expression Omnibus database were analyzed to screen differentially expressed lncRNAs (DElncRNAs) and mRNAs (DEmRNAs). Univariate and multivariate Cox regression analyses were used to identify optimal prognosis-related DElncRNAs for constructing a risk score model. 39 common DElncRNAs and 185 common DEmRNAs were identified to construct a lncRNA-mRNA regulatory relationship network. DElncRNAs were revealed to regulate immune cell activation and proliferation. Then, 4 optimal DElncRNAs, ATP1A1-AS1, CTD-3080P12.3, EMX2OS, and LINC00645, were selected from 17 prognostic DElncRNAs to establish the 4-lncRNA risk score model. In the training set, the high-risk patients were more inclined to graft loss than the low-risk patients. Time-dependent receiver operating characteristics analysis revealed the model had good sensitivity and specificity in prediction of 1-, 2-, and 3-year graft survival after biopsy (AUC = 0.891, 0.836, and 0.733, respectively). The internal testing set verified the result well. Gene set enrichment analysis which expounded NOD-like receptor, the Toll-like receptor signaling pathways, and other else playing important role in immune response was enriched by the 4 lncRNAs. Allograft-infiltrating immune cells analysis elucidated the expression of 4 lncRNAs correlated with gamma delta T cells and eosinophils, etc. Our study identified 4 novel lncRNAs as potential biomarkers for AR of renal allograft and constructed a lncRNA-based model for predicting the risk of graft loss, which would provide new insights into mechanisms of AR.

In vitro transformation of primary human hepatocytes: Epigenetic changes and stemness properties

Human hepatocarcinogenesis is a complex process with many unresolved issues, including the cell of origin (differentiated and/or progenitor/stem cells) and the initial steps leading to tumor development. With the aim of providing new tools for studying hepatocellular carcinoma initiation and progression, we developed an innovative model based on primary human hepatocytes (PHHs) lentivirus-transduced with SV40LT+ST, HRASV12 with or without hTERT. The differentiation status of these transduced-PHHs was characterized by RNA sequencing (including lncRNAs), and the expression of some differentiation markers confirmed by RT-qPCR and immunofluorescence. In addition, their transformation capacity was assessed by colony formation in soft agar and tumorigenicity evaluated in immune-deficient mice. The co-expression of SV40LT+ST and HRASV12 in PHHs, in association or not with hTERT, led to the emergence of transformed clones. These clones exhibited a poorly differentiated cell phenotype with expression of stemness and mesenchymal-epithelial transition markers and gave rise to cancer stem cell subpopulations. In vivo, they resulted in poorly differentiated hepatocellular carcinomas with a reactivation of endogenous hTERT. These experiments demonstrate for the first time that non-cycling human mature hepatocytes can be permissive to in vitro transformation. This cellular tool provides the first comprehensive in vitro model for identifying genetic/epigenetic changes driving human hepatocarcinogenesis.

Transcriptomic Analysis of mRNA-lncRNA-miRNA Interactions in Hepatocellular Carcinoma

Fully elucidating the molecular mechanisms of non-coding RNAs (ncRNAs), including micro RNAs (miRNAs) and long non-coding RNAs (lncRNAs), underlying hepatocarcinogenesis is challenging. We characterized the expression profiles of ncRNAs and constructed a regulatory mRNA-lncRNA-miRNA (MLMI) network based on transcriptome sequencing (RNA-seq) of hepatocellular carcinoma (HCC, n = 9) patients. Of the identified miRNAs (n = 203) and lncRNAs (n = 1,090), we found 16 significantly differentially expressed (DE) miRNAs and three DE lncRNAs. The DE RNAs were highly enriched in 21 functional pathways implicated in HCC (p < 0.05), including p53, MAPK, and NAFLD signaling. Potential pairwise interactions between DE ncRNAs and mRNAs were fully characterized using in silico prediction and experimentally-validated evidence. We for the first time constructed a MLMI network of reciprocal interactions for 16 miRNAs, three lncRNAs, and 253 mRNAs in HCC. The predominant role of MEG3 in the MLMI network was validated by its overexpression in vitro that the expression levels of a proportion of MEG3-targeted miRNAs and mRNAs was changed significantly. Our results suggested that the comprehensive MLMI network synergistically modulated carcinogenesis, and the crosstalk of the network provides a new avenue to accurately describe the molecular mechanisms of hepatocarcinogenesis.

Long Noncoding RNA MIR17HG Promotes Colorectal Cancer Progression via miR-17-5p

Immune dysregulation plays a vital role in colorectal cancer initiation and progression. Long noncoding RNAs (lncRNA) exhibit multiple functions including regulation of gene expression. Here, we identified an immune-related lncRNA, MIR17HG, whose expression was gradually upregulated in adjacent, adenoma, and colorectal cancer tissue. MIR17HG promoted tumorigenesis and metastasis in colorectal cancer cells both in vitro and in vivo. Mechanistically, MIR17HG increased the expression of NF-κB/RELA by competitively sponging the microRNA miR-375. In addition, RELA transcriptionally activated MIR17HG in a positive feedback loop by directly binding to its promoter region. Moreover, miR-17-5p, one of the transcribed miRNAs from MIR17HG, reduced the expression of the tumor suppressor B-cell linker (BLNK), resulting in increased migration and invasion of colorectal cancer cells. MIR17HG also upregulated PD-L1, indicating its potential role in immunotherapy. Overall, these findings demonstrate that MIR17HG plays an oncogenic role in colorectal cancer and may serve as a promising therapeutic target. SIGNIFICANCE: These findings provide mechanistic insight into the role of the lncRNA MIR17HG and its miRNA members in regulating colorectal cancer carcinogenesis and progression.

Current status of clinical proteogenomics in lung cancer

Introduction: Lung cancer is the leading cause of cancer death worldwide. Proteogenomics, a way to integrate genomics, transcriptomics, and proteomics, have emerged as a way to understand molecular causes in cancer tumorigenesis. This understanding will help identify therapeutic targets that are urgently needed to improve individual patient outcomes. Areas covered: To explore underlying molecular mechanisms of lung cancer subtypes, several efforts have used proteogenomic approaches that integrate next generation sequencing (NGS) and mass spectrometry (MS)-based technologies. Expert opinion: A large-scale, MS-based, proteomic analysis, together with both NGS-based genomic data and clinicopathological information, will facilitate establishing extensive databases for lung cancer subtypes that can be used for further proteogenomic analyzes. Proteogenomic strategies will further be understanding of how major driver mutations affect downstream molecular networks, resulting in lung cancer progression and malignancy, and how therapy-resistant cancers resistant are molecularly structured. These strategies require advanced bioinformatics based on a dynamic theory of network systems, rather than statistics, to accurately identify mutant proteins and their affected key networks.

LncRNA-H19 promotes hepatic lipogenesis by directly regulating miR-130a/PPARγ axis in non-alcoholic fatty liver disease

Background: As one of the most common liver disorders worldwide, non-alcoholic fatty liver disease (NAFLD) begins with the abnormal accumulation of triglyceride (TG) in the liver. Long non-coding RNA-H19 was reported to modulate hepatic metabolic homeostasis in NAFLD. However, its molecular mechanism of NAFLD was not fully clear.Methods:In vitro and in vivo models of NAFLD were established by free fatty acid (FFA) treatment of hepatocytes and high-fat feeding mice, respectively. Hematoxylin and Eosin (H&E) and Oil-Red O staining detected liver tissue morphology and lipid accumulation. Immunohistochemistry (IHC) staining examined peroxisome proliferator-activated receptor γ (PPARγ) level in liver tissues. ELISA assay assessed TG secretion. Luciferase assay and RNA pull down were used to validate regulatory mechanism among H19, miR-130a and PPARγ. The gene expression in hepatocytes and liver tissues was detected by quantitative real-time PCR (qRT-PCR) and Western blotting.Results: H19 and PPARγ were up-regulated, while miR-130a was down-regulated in NAFLD mouse and cellular model. H&E and Oil-Red O staining indicated an increased lipid accumulation. Knockdown of H19 inhibited steatosis and TG secretion in FFA-induced hepatocytes. H19 could bind to miR-130a, and miR-130a could directly inhibit PPARγ expression. Meanwhile, miR-130a inhibited lipid accumulation by down-regulating NAFLD-related genes PPARγ, SREBP1, SCD1, ACC1 and FASN. Overexpression of miR-130a and PPARγ antagonist GW9662 inhibited lipogenesis and TG secretion, and PPARγ agonist GW1929 reversed this change induced by miR-130a up-regulation.Conclusion: Knockdown of H19 alleviated hepatic lipogenesis via directly regulating miR-130a/PPARγ axis, which is a novel mechanistic role of H19 in the regulation of NAFLD.

Identification of key modules and hub genes for small-cell lung carcinoma and large-cell neuroendocrine lung carcinoma by weighted gene co-expression network analysis of clinical tissue-proteomes

Small-cell lung carcinoma (SCLC) and large-cell neuroendocrine lung carcinoma (LCNEC) are high-grade lung neuroendocrine tumors (NET). However, comparative protein expression within SCLC and LCNEC remains unclear. Here, protein expression profiles were obtained via mass spectrometry-based proteomic analysis. Weighted gene co-expression network analysis (WGCNA) identified co-expressed modules and hub genes. Of 34 identified modules, six were significant and selected for protein-protein interaction (PPI) network analysis and pathway enrichment. Within the six modules, the activation of cellular processes and complexes, such as alternative mRNA splicing, translation initiation, nucleosome remodeling and deacetylase (NuRD) complex, SWItch/Sucrose Non-Fermentable (SWI/SNF) superfamily-type complex, chromatin remodeling pathway, and mRNA metabolic processes, were significant to SCLC. Modules enriched in processes, including signal recognition particle (SRP)-dependent co-translational protein targeting to membrane, nuclear-transcribed mRNA catabolic process of nonsense-mediated decay (NMD), and cellular macromolecule catabolic process, were characteristically activated in LCNEC. Novel high-degree hub genes were identified for each module. Master and upstream regulators were predicted via causal network analysis. This study provides an understanding of the molecular differences in tumorigenesis and malignancy between SCLC and LCNEC and may help identify potential therapeutic targets.

Co-expression network analysis identifies gonad- and embryo-associated protein modules in the sentinel species Gammarus fossarum

Next generation sequencing and mass spectrometry technologies have recently expanded the availability of whole transcriptomes and proteomes beyond classical model organisms in molecular biology, even in absence of an annotated genome. However, the fragmented nature of transcriptomic and proteomic data reduces the ability to interpret the data, notably in non-model organisms. Network-based approaches may help extracting important biological information from -omics datasets. The reproductive cycle of the freshwater crustacean Gammarus fossarum.provides an excellent case study to test the relevance of a network analysis in non-model organisms. Here, we illustrated how the use of a co-expression network analysis (based on Weighted Gene Co-expression Network Analysis algorithm, WGCNA) allowed identifying protein modules whose expression profiles described germ cell maturation and embryonic development in the freshwater crustacean Gammarus fossarum. Proteome datasets included testes, ovaries or embryos samples at different maturation or developmental stages, respectively. We identified an embryonic module correlated with mid-developmental stages corresponding to the organogenesis and it was characterized by enrichment in proteins involved in RNA editing and splicing. An ovarian module was enriched in vitellogenin-like proteins and clottable proteins, confirming the diversity of proteins belonging to the large lipid transfer family involved in oocytes maturations in this freshwater amphipod. Moreover, our results found evidence of a fine-tuned regulation between energy production by glycolysis and actin-myosin-dependent events in G. fossarum spermatogenesis. This study illustrates the importance of applying systems biology approaches to emergent animal models to improve the understanding of the molecular mechanisms regulating important physiological events with ecological relevance.

CRNDE enhances neuropathic pain via modulating miR-136/IL6R axis in CCI rat models

Neuropathic pain has been reported as a type of chronic pain due to the primary dysfunction of the somatosensory nervous system. It is the most serious types of chronic pain, which can lead to a significant public health burden. But, the understanding of the cellular and molecular pathogenesis of neuropathic pain is barely complete. Long noncoding RNAs (lncRNAs) have recently been regarded as modulators of neuronal functions. Growing studies have indicated lncRNAs can exert crucial roles in the development of neuropathic pain. Therefore, our present study focused on the potential role of the lncRNA Colorectal Neoplasia Differentially Expressed (CRNDE) in neuropathic pain progression. Firstly, a chronic constrictive injury (CCI) rat model was built. CRNDE was obviously increased in CCI rats. Interestingly, overexpression of CRNDE enhanced neuropathic pain behaviors. Neuroinflammation was induced by CRNDE and as demonstrated, interleukin-10 (IL-10), IL-1, IL-6, and tumor necrosis factor-α (TNF-α) protein levels in CCI rats were activated by LV-CRNDE. For another, miR-136 was obviously reduced in CCI rats. Previously, it is indicated that miR-136 participates in the spinal cord injury via an inflammation in a rat model. Here, firstly, we verified miR-136 could serve as CRNDE target. Loss of miR-136 triggered neuropathic pain remarkably via the neuroinflammation activation. Additionally, IL6R was indicated as a target of miR-136 and miR-136 regulated its expression. Subsequently, we confirmed that CRNDE could induce interleukin 6 receptor (IL6R) expression positively. Overall, it was implied that CRNDE promoted neuropathic pain progression via modulating miR-136/IL6R axis in CCI rat models.

LncRNA ZEB1-AS1 reduces liver cancer cell proliferation by targeting miR-365a-3p

Liver carcinoma is one of the most common malignancies worldwide. Previous studies have demonstrated that long non-coding RNAs (lncRNAs) are crucial mediators that participate in a wide range of molecular processes associated with carcinogenesis. However, little is known about the specific mechanisms that underlie the majority of lncRNAs. Many studies have indicated that lncRNAs affect microRNA (miRNA or miR) activities via physical base-paired binding, therefore serving as competing endogenous RNAs (ceRNAs) that indirectly regulate the expression of miRNA targets. In the current study, it was revealed that lncRNA zinc-finger E-box binding homeobox 1 antisense 1 (ZEB1-AS1) serves as a ceRNA for miR-365a-3p, functioning to positively modulate E2F transcription factor 2 (E2F2) expression in liver cancer cells. Additionally, reverse transcription-quantitative polymerase chain reaction demonstrated that levels of ZEB1-AS1 were abnormally upregulated in liver cancer and this was positively correlated with E2F2 expression. Furthermore, high levels of ZEB1-AS1 exhibited a trend for poor survival in patients with liver cancer. Western blot analysis demonstrated that ZEB1-AS1 silencing could reduce E2F2 expression. EdU staining and flow cytometry analysis indicated that downregulation of ZEB1-AS1 could suppress cell proliferation and decrease the S phase proportion of liver cancer cells, which was effectively reversed by the inhibition of miR-365a-3p. ZEB1-AS1 was also determined to be physically associated with miR-365a-3p, while miR-365a-3p was revealed to target the E2F2 3′UTR for degradation or translational repression. The results also demonstrated that ZEB1-AS1 positively regulates E2F2 expression by competitively binding to miR-365a-3p. It was further revealed to enhance liver cancer cell proliferation. Thus, these results indicate that ZEB1-AS1 is required for liver cancer progression in a ceRNA dependent manner. ZEB1-AS1 may therefore be a potential target for liver cancer intervention.

Novel mechanisms of regulation of the expression and transcriptional activity of hepatocyte nuclear factor 4α

Hepatocyte nuclear factor 4α (HNF4α) is a master regulator of development and function of digestive tissues. The HNF4A gene uses two separate promoters P1 and P2, with P1 products predominant in adult liver, whereas P2 products prevalent in fetal liver, pancreas, and liver/colon cancer. To date, the mechanisms for the regulation of HNF4A and the dynamic switch of P1-HNF4α and P2-HNF4α during ontogenesis and carcinogenesis are still obscure. Our study validated the previously reported self-stimulation of P1-HNF4α but invalidated the reported synergism between HNF4α and HNF1α. HNF4A-AS1, a long noncoding RNA, is localized between the P2 and P1 promoters of HNF4A. We identified critical roles of P1-HNF4α in regulating the expression of HNF4A-AS1 and its mouse ortholog Hnf4a-os. Paired box 6 (PAX6), a master regulator of pancreas development overexpressed in colon cancer, cooperated with HNF1α to induce P2-HNF4α but antagonized HNF4α in HNF4A-AS1 expression. Thus, PAX6 may be important in determining ontogenic and carcinogenic changes of P2-HNF4α and HNF4A-AS1 in the pancreas and intestine. We also interrogated transactivation activities on multiple gene targets by multiple known and novel HNF4α mutants identified in patients with maturity onset diabetes of the young 1 (MODY1) and liver cancer. Particularly, HNF4α-D78A and HNF4α-G79S, two mutants found in liver cancer with mutations in DNA-binding domain, displayed highly gene-specific transactivation activities. Interestingly, HNF4α-Q277X, a MODY1 truncation mutant, antagonized the transactivation activities of HNF1α and farnesoid X receptor, key regulators of insulin secretion. Taken together, our study provides novel mechanistic insights regarding the transcriptional regulation and transactivation activity of HNF4α in digestive tissues.

Four long noncoding RNAs as potential prognostic biomarkers for hepatocellular carcinoma

The study aimed to identify the long noncoding RNAs (lncRNAs) biomarkers for occurrence and prognosis of patients with hepatocellular carcinoma (HCC), and simultaneously to investigate the potential role of lncRNAs in the oncogenesis of HCC. The lncRNAs expression data and the corresponding clinical information of HCC samples were extracted from The Cancer Genome Atlas (TCGA) database. The differentially expressed genes and lncRNAs were identified and the correlation networks were constructed. In this study, we identified 212 differentially expressed lncRNAs and 7,577 differentially expressed genes between liver HCC tumor tissues and normal tissue samples. And then, combining with clinical information, a total of 11 lncRNAs and 162 genes as HCC biomarkers were identified by comprehensive bioinformatics analysis. Further, through coexpress network analysis, we confirmed four lncRNAs (lncRNA_ANKRD10.IT1, lncRNA_CTD.2583A14.8, lncRNA_RP11.404P21.3, and lncRNA_RP11.488L18.10), which can serve as prognostic biomarkers for HCC. The four lncRNAs identified in this study may serve as a potential therapy target for HCC.

Serum level of co-expressed hub miRNAs as diagnostic and prognostic biomarkers for pancreatic ductal adenocarcinoma

Background: Sensitive and specific non-invasive biomarkers are urgently needed in order to improve the survival of patients with pancreatic ductal adenocarcinoma (PDAC), which is the fourth leading cause of cancer-related death. We aim to identify serum hub miRNAs as potential diagnostic and prognostic biomarkers for PDAC.

Methods: A total of 2578 serum miRNA expression data from 88 PDAC patients and 19 healthy subjects were downloaded from the Gene Expression Omnibus database. Weighted gene co-expression network analysis (WGCNA) was constructed and significant modules were extracted from the network by WGCNA R package. Network modules and hub miRNAs closely related to PDAC were identified. The prognostic value of hub miRNAs was assessed by Kaplan-Meier overall survival analysis.

Results: Two modules strongly associated with PDAC were identified by WGCNA, which were labeled as turquoise and brown respectively. Within each module, twenty hub miRNAs were found. At the functional level, turquoise module was mainly associated with tumorigenesis pathways such as P53 and WNT signaling pathway, while the brown module was mostly related to the pathways of cancer such as RNA transport and MAPK signaling pathway. Utilizing overall survival analyses, five “real” miRNAs were able to stratify PDAC patients into low-risk and high-risk groups.

Conclusions: The association of specific Hub miRNAs with the development of pancreatic cancer was established by WGCNA analysis. Five miRNAs (mir-16-2-3p, mir-890, mir-3201, mir-602, and mir-877) were identified as potential diagnostic and prognostic biomarkers for PDAC.

Long non-coding RNA CRNDE in cancer prognosis: Review and meta-analysis

BACKGROUND

Colorectal neoplasia differentially expressed (CRNDE), a 1910-nt lncRNA encoded on human chromosome 16, has been found to be involved in various cancers. Nevertheless, the clinical and diagnostic values of CRNDE in tumors still need to be explored. In this review, we aimed to elucidate the clinical role of CRNDE in cancer by searching all correlative literature, and we sequentially explored the association between CRNDE levels and overall survival (OS) or clinicopathological characteristics of cancer.

METHODS

We conducted a database search of PubMed, Wanfang Data, Ovid, SinoMed, China National Knowledge Infrastructure, Cochrane Library, and Web of Science (up to January 1, 2018). The pooled odds ratio (OR) and hazard ratio (HR) were used to assess extents of correlation between CRNDE and cancer prognosis. After identification of the inclusion and exclusion criteria, 12 articles including 1361 patients were selected for this review.

RESULTS

The results suggested that high levels of CRNDE were highly related to poor OS in tumor patients, with pooled HRs of 2.314 (1.894-2.826, P < .001, fixed-effects model). Likewise, we also found that high CRNDE expression was correlated with high tumor stage [OR: 3.340, 95% confidence interval (CI): 2.417-4.616, P < .001, random-effects model] and lymph node metastasis (OR: 3.027, 95% CI: 2.071-4.425, P = .004, random-effects model).

CONCLUSIONS

Our findings demonstrated that CRNDE may modify susceptibility for various cancers and may serve as a new predictive factor for prognosis and diagnosis in different types of cancers.

H19 Is Expressed in Hybrid Hepatocyte Nuclear Factor 4α+ Periportal Hepatocytes but Not Cytokeratin 19+ Cholangiocytes in Cholestatic Livers

Long noncoding RNA (lncRNA) H19 is abundantly expressed in fetal liver. Its expression is significantly diminished in adult healthy liver but is re‐induced in chronic liver diseases, including cholestasis. In this study, we developed a new method with combined in situ hybridization (ISH) and immunofluorescence (IF) colabeling to establish an H19 expression profile with both parenchymal and nonparenchymal cell‐specific markers in the livers of cholestatic mouse models and patients with cholestasis. H19RNA⁺ cells showed no colocalization with biliary epithelial cell marker cytokeratin 19 (CK19)⁺ cholangiocytes but were immediately adjacent to biliary structures in bile duct ligation (BDL), 3,5‐diethoxycarbony1‐1,4‐dihydrocollidine (DDC), and multidrug‐resistant gene 2 knockout (Mdr2^–/–) mouse models and in human primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) liver specimens. In contrast, double‐positive H19RNA⁺/sex‐determining region Y (SRY)‐box 9 (SOX9)⁺ ductal progenitor cells, H19RNA⁺/hepatocyte nuclear factor 4α (HNF4α)⁺ hepatocytes, H19RNA⁺/F4/80⁺ Kupffer cells, HNF4α⁺/SOX9⁺ hybrid hepatocytes, as well as triple‐positive H19RNA⁺/HNF4α⁺/SOX9⁺ periportal hepatocytes were identified. In addition, H19RNA could not be detected in mesenchymal cell marker desmin⁺ cells. Furthermore, H19RNA was predominately detected in cytoplasm with a small amount at the interspace with neighboring cells. Conclusion:H19RNA is localized in HNF4α⁺ periportal hepatocytes, SOX9⁺ ductal progenitor cells, and F4/80⁺ Kupffer cells but not in CK19⁺ cholangiocytes and desmin⁺ stellate cells in cholestatic livers.

Updates on the hepatocyte growth factor/c-Met axis in hepatocellular carcinoma and its therapeutic implications

Hepatocellular carcinoma (HCC) is the fifth most common cancer and is the second leading cause of cancer death. Since the diagnosis of HCC is difficult, in many cases patients with HCC are diagnosed advanced stage of development. Hepatocyte growth factor (HGF)/c-mesenchymal-epithelial transition receptor (c-Met) axis is a key signaling pathway in HCC, either via canonical or non-canonical pathways. Available treatments against HCC based upon HGF/c-Met inhibition can increase patient lifespan, but do not reach the expected therapeutic benefits. In HCC, c-Met monomers can bind other receptor monomers, activating several noncanonical signaling pathways, leading to increased cell proliferation, invasion, motility, and drug resistance. All of these processes are enhanced by the tumor microenvironment, with stromal cells contributing to boost tumor progression through oxidative stress, angiogenesis, lymphangiogenesis, inflammation, and fibrosis. Novel treatments against HCC are being explored to modulate other targets such as microRNAs, methyltransferases, and acetyltransferases, which are all involved in the regulation of gene expression in cancer. This review compiles basic knowledge regarding signaling pathways in HCC, and compounds already used or showing potential to be used in clinical trials.

LncRNA CRNDE is a biomarker for clinical progression and poor prognosis in clear cell renal cell carcinoma

Colorectal neoplasia differentially expressed (CRNDE) served as an oncogenic long noncoding RNA (lncRNA) to be involved in the initialization and development of human cancers. However, the clinical significance and biological function of CRNDE in clear cell renal cell carcinoma (ccRCC) was not fully understood. In our study, we found CRNDE levels were increased in ccRCC tissue specimens and cell lines, and corrected with advanced clinical stage, large tumor size, lymph node metastasis, distant metastasis, and poor pathological grade in patients with ccRCC. Furthermore, levels of CRNDE were negatively correlated with overall survival of patients with ccRCC, and high-expression of CRNDE was an independent poor prognostic factor for patients with ccRCC. Moreover, loss-of-function and gain-of-function approaches showed CRNDE-enhanced ccRCC cell migration and invasion through modulating EMT-associated genes. In conclusion, CRNDE acts as an oncogenic lncRNA in ccRCC.

Colorectal neoplasia differentially expressed: a long noncoding RNA with an imperative role in cancer

Colorectal neoplasia differentially expressed (CRNDE), as a long noncoding RNA (lncRNA), has attracted increasing attention in recent years and has been documented to be at abnormally high expression in various types of cancer, such as colorectal cancer, glioma, hepatocellular carcinoma, lung cancer, and breast cancer. It could not only be used as a clinical biomarker for the early diagnosis and prognosis evaluation in a variety of cancers but also promote the development and progress of various tumor cells. Moreover, it is involved in the targeting regulation of multiple microRNAs and the activation/inhibition of multiple signaling pathways. In this review, we presented a systematic summary of the potential carcinogenicity and clinical value of CRNDE in the current evidence, so as to provide reference for early diagnosis, prognosis evaluation, and targeted therapy of various clinical cancers.