SND1 acts as an anti-apoptotic factor via regulating the expression of lncRNA UCA1 in hepatocellular carcinoma

SND1 Regulates Organic Anion Transporter 2 Protein Expression and Sensitivity of Hepatocellular Carcinoma Cells to 5-Fluorouracil

Hepatocellular carcinoma (HCC) is one of the most malignant tumors in the world. Inadequate efficacy of 5-fluorouracil (5-FU) on HCC could be related to low expression of human organic anion transporter 2 (OAT2). However, the knowledge of downregulation of OAT2 in HCC remains limited. We explored the underlying mechanism focusing on protein expression regulation and attempted to design a strategy to sensitize HCC cells to 5-FU. In this study, we revealed that the 1 bp to 300 bp region of OAT2 mRNA 3' untranslated region (UTR) reduced its protein expression and uptake activity in Li-7 and PLC/PRF/5 cells. Mechanistically, it was demonstrated that staphylococcal nuclease and Tudor domain containing 1 (SND1) bound at the 1 bp to 300 bp region of OAT2 mRNA 3' UTR, leading to a decrease in OAT2 protein expression. Enrichment analysis results indicated reduction of OAT2 might be mediated by translational inhibition. Furthermore, the knockdown of SND1 upregulated OAT2 protein expression and uptake activity. Based on this, decreasing SND1 expression enhanced 5-FU-caused G1/S phase arrest in Li-7 and PLC/PRF/5 cells, resulting in suppression of cell proliferation. Additionally, the knockdown of SND1 augmented the inhibitory effect of 5-FU on PLC/PRF/5 xenograft tumor growth in vivo by increasing OAT2 protein expression and accumulation of 5-FU in the tumor. Collectively, a combination of inhibition of SND1 with 5-FU might be a potential strategy to sensitize HCC cells to 5-FU from the perspective of restoring OAT2 protein level. SIGNIFICANCE STATEMENT: We investigated the regulatory mechanism of OAT2 protein expression in HCC cells and designed a strategy to sensitize them to 5-FU (OAT2 substrate) via restoring OAT2 protein level. It found that SND1, an RNA binding protein, regulated OAT2 protein expression by interacting with OAT2 mRNA 3' UTR 1-300 bp region. Through decreasing SND1, the antitumor effect of 5-FU on HCC was enhanced in vitro and in vivo, indicating that SND1 could be a potential target for sensitizing HCC cells to 5-FU.

Hypomethylation-associated LINC00987 downregulation induced lung adenocarcinoma progression by inhibiting the phosphorylation-mediated degradation of SND1

DNA methylation, an epigenetic regulatory mechanism dictating gene transcription, plays a critical role in the occurrence and development of cancer. However, the molecular underpinnings of LINC00987 methylation in the regulation of lung adenocarcinoma (LUAD) remain elusive. This study investigated LINC00987 expression in LUAD patients through analysis of The Cancer Genome Atlas data sets. Quantitative real-time polymerase chain reaction (RT-qPCR) and fluorescence in situ hybridization assays were used to assess LINC00987 expression in LUAD. The bisulfite genomic sequence PCR (BSP) assay was used to determine the methylation levels of the LINC00987 promoter. The interaction between LINC00987 and SND1 was elucidated via immunoprecipitation and RNA pull-down assays. The functional significance of LINC00987 and SND1 in Calu-3 and NCI-H1688 cells was evaluated in vitro through CCK-8, EdU, Transwell, flow cytometry, and vasculogenic mimicry (VM) tube formation assays. LINC00987 expression decreased in LUAD concomitant with hypermethylation of the promoter region, while hypomethylation of the LINC00987 promoter in LUAD tissues correlated with tumor progression. Treatment with 5-Aza-CdR augmented LINC00987 expression and inhibited tumor growth. Mechanistically, LINC00987 overexpression impeded LUAD progression and VM through direct binding with SND1, thereby facilitating its phosphorylation and subsequent degradation. Additionally, overexpression of SND1 counteracted the adverse effects of LINC00987 downregulation on cell proliferation, apoptosis, cell migration, invasion, and VM in LUAD in vitro. In conclusion, this pioneering study focuses on the expression and function of LINC00987 and reveals that hypermethylation of the LINC00987 gene may contribute to LUAD progression. LINC00987 has emerged as a potential tumor suppressor gene in tumorigenesis through its binding with SND1 to facilitate its phosphorylation and subsequent degradation.

EGC enhances tumor antigen presentation and CD8+ T cell-mediated antitumor immunity via targeting oncoprotein SND1

The Staphylococcal nuclease and Tudor domain containing 1 (SND1) has been identified as an oncoprotein. Our previous study demonstrated that SND1 impedes the major histocompatibility complex class I (MHC-I) assembly by hijacking the nascent heavy chain of MHC-I to endoplasmic reticulum-associated degradation. Herein, we aimed to identify inhibitors to block SND1-MHC-I binding, to facilitate the MHC-I presentation and tumor immunotherapy. Our findings validated the importance of the K490-containing sites in SND1-MHC-I complex. Through structure-based virtual screening and docking analysis, (-)-Epigallocatechin (EGC) exhibited the highest docking score to prevent the binding of MHC-I to SND1 by altering the spatial conformation of SND1. Additionally, EGC treatment resulted in increased expression levels of membrane-presented MHC-I in tumor cells. The C57BL/6J murine orthotopic melanoma model validated that EGC increases infiltration and activity of CD8+ T cells in both the tumor and spleen. Furthermore, the combination of EGC with programmed death-1 (PD-1) antibody demonstrated a superior antitumor effect. In summary, we identified EGC as a novel inhibitor of SND1-MHC-I interaction, prompting MHC-I presentation to improve CD8+ T cell response within the tumor microenvironment. This discovery presents a promising immunotherapeutic candidate for tumors.

New insights into the interaction between m6A modification and lncRNA in cancer drug resistance

Drug resistance is perhaps the greatest obstacle in improving outcomes for cancer patients, leading to recurrence, progression and metastasis of various cancers. Exploring the underlying mechanism worth further study. N6-methyladenosine (m6A) is the most common RNA modification found in eukaryotes, playing a vital role in RNA translation, transportation, stability, degradation, splicing and processing. Long noncoding RNA (lncRNA) refers to a group of transcripts that are longer than 200 nucleotides (nt) and typically lack the ability to code for proteins. LncRNA has been identified to play a significant role in regulating multiple aspects of tumour development and progression, including proliferation, metastasis, metabolism, and resistance to treatment. In recent years, a growing body of evidence has emerged, highlighting the crucial role of the interplay between m6A modification and lncRNA in determining the sensitivity of cancer cells to chemotherapeutic agents. In this review, we focus on the recent advancements in the interaction between m6A modification and lncRNA in the modulation of cancer drug resistance. Additionally, we aim to explore the underlying mechanisms involved in this process. The objective of this review is to provide valuable insights and suggest potential future directions for the reversal of chemoresistance in cancer.

SNHG1, interacting with SND1, contributes to sorafenib resistance of liver cancer cells by increasing m6A-mediated SLC7A11 expression and promoting aerobic glycolysis

Aerobic glycolysis plays an important role in multidrug resistance of cancer cells. Here, we screened different expressed lncRNAs associated with sorafenib resistance of liver cancer cells, by intersecting the bioinformatics analyses of TCGA and GEO (the GSE62813 dataset) databases. Our results revealed that the 18 upregulated lncRNAs in the intersection are associated with and enriched in metabolism of small molecule organic acids, suggesting their potential in glycolysis. The lncRNA small nucleolar RNA host gene 1 (Snhg1) was chosen as a potential regulator of aerobic glycolysis in liver cancer cells, for its significant promotion on lactate production. Gain- and loss-of-function experiments mediated by Crispr-Cas9 technique in HepG2 cells indicated that Snhg1 promoted cell proliferation, invasion, sorafenib resistance, and aerobic glycolysis. In the mechanism exploration, we found that Snhg1 can interact with SND1 protein, a famous RNA binding protein and recently identified "Reader" of N6-methyladenosine (m6A). SND1 was demonstrated to be positively regulated by Snhg1 and had similar promoting effects on proliferation, invasion, sorafenib resistance, and aerobic glycolysis of HepG2 cells. SND1 bound with and promoted the expression of SLC7A11, an aerobic glycolysis regulator. Furthermore, either silencing SLC7A11 or blocking aerobic glycolysis with 2-deoxy-d-glucose (2-DG) was able to reverse the promotion of Snhg1 overexpression on malignancy, sorafenib resistance, and aerobic glycolysis of HepG2 cells. Finally, in a liver cancer xenograft mouse model, we found that formed tumors with Snhg1-knocked-down HepG2 cells were more sensitive to sorafenib administration. Altogether, SNHG1 contributes to sorafenib resistance of liver cancer cells by promoting SND1-m6A-SLC7A11-mediated aerobic glycolysis.

SND1, a novel co-activator of HIF1α, promotes tumor initiation in PyMT-induced breast tumor

The multifunctional protein staphylococcal nuclease domain-containing protein 1 (SND1) is conserved and has been implicated in several aspects of tumor development, such as proliferation, epithelial-mesenchymal transition, and immune evasion. Despite this, the precise role of SND1 in the initiation and metastasis of mammary gland tumors remains largely unexplored. In this study, we utilized a mouse model of breast tumors induced by polyomavirus middle T antigen (PyMT) to demonstrate that the knockout of SND1 significantly delayed the onset of primary mammary tumor formation induced by PyMT. Histological staining and cytometric analysis were conducted to confirm the reduction of tumor-initiating cells and lung metastasis following depletion of SND1. Additionally, our findings demonstrate that enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2), a crucial epigenetic modifier implicated in PyMT-induced breast tumors, serves as an essential mediator of SND1-promoted primary mammary tumor formation. Mechanistic investigations revealed that SND1 functions as a transcriptional co-activator of hypoxia-inducible factor 1 subunit alpha (HIF1α), thereby regulating the downstream target gene EZH2 and promoting tumorigenesis. Overall, this study provides novel insights into the role of SND1 as a co-activator of HIF1α in the acceleration of PyMT-induced spontaneous breast tumor formation through the promotion of EZH2 transcription. The findings provide novel insights into the relationship between SND1 and the formation of tumor-initiating cells.

Spatiotemporal Investigation of Intercellular Heterogeneity via Multiple Photocaged Probes

Intercellular heterogeneity occurs widely under both normal physiological environments and abnormal disease-causing conditions. Several attempts to couple spatiotemporal information to cell states in a microenvironment were performed to decipher the cause and effect of heterogeneity. Furthermore, spatiotemporal manipulation can be achieved with the use of photocaged/photoactivatable molecules. Here, we provide a platform to spatiotemporally analyze differential protein expression in neighboring cells by multiple photocaged probes coupled with homemade photomasks. We successfully established intercellular heterogeneity (photoactivable ROS trigger) and mapped the targets (directly ROS-affected cells) and bystanders (surrounding cells), which were further characterized by total proteomic and cysteinomic analysis. Different protein profiles were shown between bystanders and target cells in both total proteome and cysteinome. Our strategy should expand the toolkit of spatiotemporal mapping for elucidating intercellular heterogeneity.

Candidate genes for domestication and resistance to cold climate according to whole genome sequencing data of Russian cattle and sheep breeds

It is known that different species of animals, when living in the same environmental conditions, can form similar phenotypes. The study of the convergent evolution of several species under the influence of the same environmental factor makes it possible to identify common mechanisms of genetic adaptation. Local cattle and sheep breeds have been formed over thousands of years under the influence of domestication, as well as selection aimed at adaptation to the local environment and meeting human needs. Previously, we identified a number of candidate genes in genome regions potentially selected during domestication and adaptation to the climatic conditions of Russia, in local breeds of cattle and sheep using whole genome genotyping data. However, these data are of low resolution and do not reveal most nucleotide substitutions. The aim of the work was to create, using the whole genome sequencing data, a list of genes associated with domestication, selection and adaptation in Russian cattle and sheep breeds, as well as to identify candidate genes and metabolic pathways for selection for cold adaptation. We used our original data on the search for signatures of selection in the genomes of Russian cattle (Yakut, Kholmogory, Buryat, Wagyu) and sheep (Baikal, Tuva) breeds. We used the HapFLK, DCMS, FST and PBS methods to identify DNA regions with signatures of selection. The number of candidate genes in potentially selective regions was 946 in cattle and 151 in sheep. We showed that the studied Russian cattle and sheep breeds have at least 10 genes in common, apparently involved in the processes of adaptation/selection, including adaptation to a cold climate, including the ASTN2, PM20D1, TMEM176A, and GLIS1 genes. Based on the intersection with the list of selected genes in at least two Arctic/Antarctic mammal species, 20 and 8 genes, have been identified in cattle and sheep, respectively, that are potentially involved in cold adaptation. Among them, the most promising for further research are the ASPH, NCKAP5L, SERPINF1, and SND1 genes. Gene ontology analysis indicated the existence of possible common biochemical pathways for adaptation to cold in domestic and wild mammals associated with cytoskeleton disassembly and apoptosis.

A review on CRISPR/Cas: a versatile tool for cancer screening, diagnosis, and clinic treatment

Cancer is one of the leading causes of death worldwide and it has the trend of increase incidence. However, in the past decades, as quickly developed new technologies and modified old techniques for cancer screening, diagnosis, and treatment, the cancer-caused mortality rates dropped quickly, and the survival times of cancer patients are enhanced. However, the current death rate is still about 50% and the survival patients always suffer from the side effect of current cancer treatments. Recently developed Nobel Prize-winning CRISPR/Cas technology provides new hope on cancer screening, early diagnosis, and clinic treatment as well as new drug development. Currently, four major CRISPR/Cas9-derived genome editors, CRISPR/Cas9 nucleotide sequence editor, CRISPR/Cas base editor (BE), CRISPR prime editor (PE), and CRISPR interference (CRISPRi) (including both CRISPRa and CRISPRr), were well developed and used to various research and applications, including cancer biology study and cancer screening, diagnosis, and treatment. Additionally, CRISPR/Cas12 and CRISPR/Cas13 genome editors were also widely used in cancer-related basic and applied research as well as treatment. Cancer-associated SNPs and genetic mutations as well as both oncogenes and tumor suppressor genes are perfect targets for CRISPR/Cas-based gene therapy for cancer treatment. CRISPR/Cas is also employed to modify and generate new Chimeric antigen receptor (CAR) T-cells for improving its safety, efficiency, and longer-time last for treating various cancers. Currently, there are many clinic trails of CRISPR-based gene therapy for cancer treatments. Although all CRISPR/Cas-derived genome and epigenome tools are promising methods for cancer biology study and treatment, the efficiency and long term-safety are still the major concerns for CRISPR-based gene therapy. Developing new CRISPR/Cas delivery methods and reducing the potential side effects, including off-target impacts, will enhance CRISPR/Cas application in cancer-related research, diagnosis, and therapeutical treatment.

Signal Pathways and microRNAs in Osteosarcoma Growth and the Dual Role of Mesenchymal Stem Cells in Oncogenesis

The major challenges in Osteosarcoma (OS) therapy are its heterogeneity and drug resistance. The development of new therapeutic approaches to overcome the major growth mechanisms of OS is urgently needed. The search for specific molecular targets and promising innovative approaches in OS therapy, including drug delivery methods, is an urgent problem. Modern regenerative medicine focuses on harnessing the potential of mesenchymal stem cells (MSCs) because they have low immunogenicity. MSCs are important cells that have received considerable attention in cancer research. Currently, new cell-based methods for using MSCs in medicine are being actively investigated and tested, especially as carriers for chemotherapeutics, nanoparticles, and photosensitizers. However, despite the inexhaustible regenerative potential and known anticancer properties of MSCs, they may trigger the development and progression of bone tumors. A better understanding of the complex cellular and molecular mechanisms of OS pathogenesis is essential to identify novel molecular effectors involved in oncogenesis. The current review focuses on signaling pathways and miRNAs involved in the development of OS and describes the role of MSCs in oncogenesis and their potential for antitumor cell-based therapy.

Alternatively-spliced lncRNA-PNUTS promotes HCC cell EMT via regulating ZEB1 expression

BACKGROUND

Long non-coding RNAs have been implicated in various cancers as they regulate critical cellular processes such as proliferation, migration, invasion, and apoptosis in tumorous tissues. lncRNA-PNUTS is newly reported as an alternatively-spliced lncRNA from PNUTS pre-mRNA that promotes oncogenesis in breast cancer. However, whether LncRNA-PNUTS plays a role in other forms of cancers, such as liver cancer, remains unknown.

METHOD

In the current study, we investigated the potential role of lncRNA-PNUTS in hepatocellular carcinoma (HCC). The levels of lncRNA-PNUTS in tumorous tissues obtained from HCC patients were measured. The potential impacts of lncPNUTS on metastasis and invasion were investigated through gain- or loss- of function experiments in cell models of liver cancers, as well as other cellular assays such as trans-well assays and wound-healing assays.

RESULTS

Here, we report that lncPNUTS was upregulated in human HCC tissues. Loss- and gain-of-function experiments indicated lncPNUTS promoted metastasis and invasion. In addition, ZEB1, which is involved in the activation of epithelial-mesenchymal-transition (EMT), was identified as a downstream target of lncPNUTS.

CONCLUSION

Our findings indicated lncPNUTS promotes HCC cancer cell metastasis and invasion via targeting ZEB1 to activate the EMT pathway, suggesting that lncPNUTS is a potential prognostic marker and therapeutic target for HCC patients.

Inhibition of SND1 overcomes chemoresistance in bladder cancer cells by promoting ferroptosis

Chemotherapy remains one of the most important adjuvant treatments for bladder cancer (BC). However, similar to other malignancies, BC is prone to chemotherapy resistance and only approximately half of muscle‑invasive patients with BC respond to chemotherapy. The present study aimed to reveal the mechanisms underlying chemoresistance in BC cells. Cell viabilities were assessed by CCK‑8 assay. The differentiated expression of genes in chemoresistant and their parental BC cells were examined by RNA sequencing. Cell death was determined by flow cytometry. Different cell death inhibitors were used to determine the types of cell death. Levels of reactive oxygen species, iron, glutathione and malondialdehyde were assessed using the corresponding commercial kits. ChIP and dual luciferase activity assays were performed to investigate the interaction between staphylococcal nuclease and tumour domain containing 1 (SND1) and glutathione peroxidase 4 (GPX4) mRNA. RNAi was used to knockdown SND1 or GPX4. The results revealed that SND1 in BC cells were insensitive to cisplatin, and inhibition of SND1 overcame this resistance. Silencing of SND1 enhanced cell death induced by cisplatin by promoting ferroptosis in BC cells. Mechanistically, SND1 was revealed to bind to the 3'UTR region of GPX4 mRNA and stabilise it. Knockdown of GPX4 could also overcome chemoresistance, and overexpressing GPX4 reversed the effects of silencing of GPX4 on the chemosensitivity of BC cells. Thus, targeting the SND1‑GPX4 axis may be a potential strategy to overcome chemoresistance in BC cells.

Molecular Design, Spectroscopic, DFT, Pharmacological, and Molecular Docking Studies of Novel Ruthenium(III)-Schiff Base Complex: An Inhibitor of Progression in HepG2 Cells

A novel ruthenium(III)-pyrimidine Schiff base was synthesized and characterized using different analytical and spectroscopic techniques. Molecular geometries of the ligand and ruthenium complex were investigated using the DFT-B3LYP level of theory. The quantum global reactivity descriptors were also calculated. Various biological and molecular docking studies of the complex are reported to explore its potential application as a therapeutic drug. Cytotoxicity of the complex was screened against cancer colorectal (HCT116), breast (MCF-7 and T47D), and hepatocellular (HepG2) cell lines as well as a human normal cell line (HSF). The complex effectively inhibited the tested cancer cells with variable degree with higher activity towards HepG2 (IC₅₀ values were 29 μM for HepG2, 38.5 μM for T47D, 39.7 μM for HCT, and 46.7 μM for MCF-7 cells). The complex induced apoptosis and cell cycle arrest in the S phase of HepG2 cells. The complex significantly induced the expression of H2AX and caspase 3 and caspase 7 gene and the protein level of caspase 3, as well as inhibited VEGF-A and mTOR/AKT, SND1, and NF-kB gene expression. The molecular docking studies supported the increased total apoptosis of treated HepG2 cells due to strong interaction of the complex with DNA. Additionally, the possible binding interaction of the complex with caspase 3 could be responsible for the elevated activity of caspase 3-treated cells. The score values for the two receptors were -3.25 and -3.91 kcal/mol.

TGF-β1/Smad3 upregulates UCA1 to promote liver fibrosis through DKK1 and miR18a

TGF-β1 is the strongest cytokine known to promote liver fibrosis. It has been previously demonstrated that the activation of TGF-β1 initiates a temporary collagen accumulation program, which is important for wound repair in several organs. Furthermore, temporary extracellular matrix enhancement often leads to progressive fibrosis, which is accountable for cases of severe morbidity and mortality worldwide. However, its action mechanism has not been fully explored. It was previously reported that UCA1 could promote its occurrence and development in various tumors. Importantly, it was reported that TGF-β1 could activate the expression of UCA1 in liver cancer, gastric cancer, and breast cancer. However, the role of UCA1 in organ fibrosis, including liver fibrosis, remains unreported. The present study reported for the first time that TGF-β1/Smad3 could promote liver fibrosis by upregulating UCA1, which further affected DKK1 and collagen, such as COL1A1, COL1A2, and COL3A1. Meanwhile, UCA1 could competitively bind with miR18a to stabilize Smad3 to constitute a positive feedback pathway, which played a significant role in the promotion of liver fibrosis. Altogether, the present study provides a theoretical basis for devising promising treatment strategies for liver fibrosis. KEY MESSAGES : UCA1 was found to promote the progression of liver fibrosis in vitro. UCA1 is regulated by TGF-β1 and promotes liver fibrosis through the canonical Smad pathway. UCA1 can competitively bind with miR18a, promote liver fibrosis by stabilizing Smad3, and form a UCA1-miR18a/Smad3 positive feedback. UCA1 binds EZH2 to inhibit the DKK1 expression and promote liver fibrosis.

SND1 confers chemoresistance to cisplatin-induced apoptosis by targeting GAS6-AKT in SKOV3 ovarian cancer cells

Platinum-based (especially cisplatin) chemotherapy is the main treatment after surgery for ovarian cancer. Although the initial treatment is effective, chemotherapy resistance develops rapidly. Therefore, chemotherapy resistance has always been a huge obstacle in the treatment of ovarian cancer. Staphylococcal nuclease domain-containing protein 1 (SND1) is an evolutionarily conserved multifunctional protein that plays a role in promoting tumorigenesis under various stress states. In this study, using MTT and SKOV3 ovarian cancer cells deficient in SND1 were observed to be more apoptotic and to express more apoptotic protein after treatment with cisplatin through the MTT, clone formation, and flow cytometry assays, while cells overexpressing SND1 exhibited a decreased number of apoptotic cells and expression of apoptotic proteins. Moreover, SND1 can regulate the expression of Growth arrest-specific 6 (GAS6) and then activate the AKT signaling pathway to achieve the regulation of sensitivity to cisplatin-induced apoptosis in ovarian cancer.

MiR-152-5p suppresses osteogenic differentiation of mandible mesenchymal stem cells by regulating ATG14-mediated autophagy

BACKGROUND

Osteoporosis affects the mandible resulting in bone loss. Though impairments are not life threatening, they affect a person's quality-of-life particularly vulnerable elderly. MicroRNAs (miRNAs) are novel regulatory factors that play an important role in regulating bone metabolism. Autophagy is evolutionarily conserved intracellular self-degradation process and is vital in the maintenance of both miRNA and bone homeostasis. However, the role of autophagy in the pathogenesis of miRNA regulating osteoporosis remains unclear.

METHODS

In the study, we established a rat osteoporosis model induced by ovariectomy (OVX) and isolated mesenchymal stem cells from mandible (MMSCs-M). Several miRNAs were identified to regulate osteoporosis in some studies. qRT-PCR was applied to examine the expression of miRNA, autophagy and osteogenic differentiation-related genes. Western blotting assays were performed to detect the expression of autophagy and osteogenic differentiation proteins. Immunofluorescence and transmission electron microscope were used to verify the autophagy activity. Transfecting technology was used to enhance or suppress the expression of miR-152-5p which enable us to observe the relationship between miR-152-5p, autophagy and osteogenic differentiation. Additionally, the measurement of reactive oxygen species was used to investigate the mechanism of autophagy affecting osteogenic differentiation.

RESULTS

We found an upregulated expression of miR-152-5p in MMSCs-M in OVX group. Downregulated autophagy-related gene, proteins and autophagosome were detected in vitro of OVX group compared with sham group. Moreover, downregulation of miR-152-5p promoted osteogenic differentiation of MMSCs-M as well as enhanced autophagy-related proteins in OVX group. Conversely, overexpression of miR-152-5p showed opposite effect in sham group. Meanwhile, we found Atg14 (autophagy-related protein homolog 14) was identified to be a direct target of miR-152-5p theoretically and functionally. In other words, we confirmed inhibition of miR-152-5p promoted the osteogenic differentiation via promoting ATG14-mediated autophagy. Furthermore, miR-152-5p/ATG14-mediated autophagy regulated osteogenic differentiation by reducing the endogenous ROS accumulation and maintaining cellular redox homeostasis.

CONCLUSION

Our data suggest that miR-152-5p is the first identified to regulate osteogenic differentiation by directly targeting autophagy-related protein ATG14 and regulating oxidative stress and therapeutic inhibition of miR-152-5p may be an efficient anabolic strategy for osteoporosis.

Mechanism for Bioactive Nanomaterial circ0024831 Regulation of Staphylococcal Nuclease Domain Containing 1 via RNA Methylation Recognition in Osteosarcoma

Bioactive nanomaterial circular RNA (circRNA) is an important non-coding RNA with a strong specificity, stable structure and high expression abundance. It can affect many diseases and physiological processes and may become a new way of disease diagnosis and targeted therapy. Recent studies have shown that Staphylococcal Nuclease Domain-Containing Protein 1 (SND1) can recognize N6-methyladenine (M6A) modified mRNA and regulate target mRNA stability. It can then control the expression of a series of downstream genes. However, whether SND1 can directly combine with circRNA and regulate its stability and function are new issues to be discussed. Results showed bioactive nanomaterial circ0024831 could directly bind to the Tudor domain of SND1 in the cytoplasm to block the recognition of SND1 to M6A modified RNA thus reducing the stability of downstream target gene mRNA and inhibiting the expression of downstream regulatory proteins. The down-regulation of circ0024831 expression in osteosarcoma cells relieved inhibition of SND1 which lead to change of tumor-related gene expression profile, promoting the occurrence and development of osteosarcoma.

Intricate crosstalk between MYB and noncoding RNAs in cancer

MYB is often overexpressed in malignant tumors and plays a carcinogenic role in the initiation and development of cancer. Deletion of the MYB regulatory C-terminal domain may be a driving mutation leading to tumorigenesis, therefore, different tumor mechanisms produce similar MYB proteins. As MYB is a transcription factor, priority has been given to identifying the genes that it regulates. All previous attention has been focused on protein-coding genes. However, an increasing number of studies have suggested that MYB can affect the complexity of cancer progression by regulating tumor-associated noncoding RNAs (ncRNAs), such as microRNAs, long-non-coding RNAs and circular RNAs. ncRNAs can regulate the expression of numerous downstream genes at the transcription, RNA processing and translation levels, thereby having various biological functions. Additionally, ncRNAs play important roles in regulating MYB expression. This review focuses on the intricate crosstalk between oncogenic MYB and ncRNAs, which play a pivotal role in tumorigenesis, including proliferation, apoptosis, angiogenesis, metastasis, senescence and drug resistance. In addition, we discuss therapeutic strategies for crosstalk between MYB and ncRNAs to prevent the occurrence and development of cancer.

Role of N6-Methyladenosine (m6A) Methylation Regulators in Hepatocellular Carcinoma

Liver cancer is the fifth most common malignant tumor in terms of incidence and the third leading cause of cancer-related mortality globally. Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer. Although great progress has been made in surgical techniques, hepatic artery chemoembolization, molecular targeting and immunotherapy, the prognosis of liver cancer patients remains very poor. N6-methyladenosine (m6A) is the most abundant internal RNA modification in eukaryotic cells and regulates various stages of the RNA life cycle. Many studies have reported that the abnormal expression of m6A-related regulators in HCC represent diagnostic and prognostic markers and potential therapeutic targets. In this review, firstly, we introduce the latest research on m6A-related regulators in detail. Next, we summarize the mechanism of each regulator in the pathogenesis and progression of HCC. Finally, we summarize the potential diagnostic, prognostic and therapeutic value of the regulators currently reported in HCC.

Impact of hepatocyte-specific deletion of staphylococcal nuclease and tudor domain containing 1 (SND1) on liver insulin resistance and acute liver failure of mice

Although our previous research shows an ameliorated high-fat diet (HFD)-induced hepatic steatosis and insulin resistance in global SND1 transgenic mice, the involvement of SND1 loss-of-function in hepatic metabolism remains elusive. Herein, we aim to explore the potential impact of hepatocyte-specific SND1 deletion on insulin-resistant mice. As SND1 is reported to be linked to inflammatory response, the pathobiological feature of acute liver failure (ALF) is also investigated. Hence, we construct the conditional liver knockout (LKO) mice of SND1 for the first time. Under the condition of HFD, the absence of hepatic SND1 affects the weight of white adipose tissue, but not the gross morphology, body weight, cholesterol level, liver weight, and hepatic steatosis of mice. Furthermore, we fail to observe significant differences in either HFD-induced insulin resistance or lipopolysaccharide/D-galactosamine-induced (LPS/D-GaIN) ALF between LKO and wild type (WT) mice in terms of inflammation and tissue damage. Compared with negative controls, there is no differential SND1 expression in various species of sample with insulin resistance or ALF, based on several gene expression omnibus datasets, including GSE23343, GSE160646, GSE120243, GSE48794, GSE13271, GSE151268, GSE62026, GSE120652, and GSE38941. Enrichment result of SND1-binding partners or related genes indicates a sequence of issues related to RNA or lipid metabolism, but not glucose homeostasis or hepatic failure. Overall, hepatic SND1 is insufficient to alter the phenotypes of hepatic insulin resistance and acute liver failure in mice. The SND1 in various organs is likely to cooperate in regulating glucose homeostasis by affecting the expression of lipid metabolism-related RNA transcripts during stress.

Tudor staphylococcal nuclease is a docking platform for stress granule components and is essential for SnRK1 activation in Arabidopsis

Tudor staphylococcal nuclease (TSN; also known as Tudor-SN, p100, or SND1) is a multifunctional, evolutionarily conserved regulator of gene expression, exhibiting cytoprotective activity in animals and plants and oncogenic activity in mammals. During stress, TSN stably associates with stress granules (SGs), in a poorly understood process. Here, we show that in the model plant Arabidopsis thaliana, TSN is an intrinsically disordered protein (IDP) acting as a scaffold for a large pool of other IDPs, enriched for conserved stress granule components as well as novel or plant-specific SG-localized proteins. While approximately 30% of TSN interactors are recruited to stress granules de novo upon stress perception, 70% form a protein-protein interaction network present before the onset of stress. Finally, we demonstrate that TSN and stress granule formation promote heat-induced activation of the evolutionarily conserved energy-sensing SNF1-related protein kinase 1 (SnRK1), the plant orthologue of mammalian AMP-activated protein kinase (AMPK). Our results establish TSN as a docking platform for stress granule proteins, with an important role in stress signalling.

Genetic expression and mutational profile analysis in different pathologic stages of hepatocellular carcinoma patients

BACKGROUND

The clinical pathologic stages (stage I, II, III-IV) of hepatocellular carcinoma (HCC) are closely linked to the clinical prognosis of patients. This study aims at investigating the gene expression and mutational profile in different clinical pathologic stages of HCC.

METHODS

Based on the TCGA-LIHC cohort, we utilized a series of analytical approaches, such as statistical analysis, random forest, decision tree, principal component analysis (PCA), to identify the differential gene expression and mutational profiles. The expression patterns of several targeting genes were also verified by analyzing the Chinese HLivH060PG02 HCC cohort, several GEO datasets, HPA database, and diethylnitrosamine-induced HCC mouse model.

RESULTS

We identified a series of targeting genes with copy number variation, which is statistically associated with gene expression. Non-synonymous mutations mainly existed in some genes (e.g.,TTN, TP53, CTNNB1). Nevertheless, no association between gene mutation frequency and pathologic stage distribution was detected. The random forest and decision tree modeling analysis data showed a group of genes related to different HCC pathologic stages, including GAS2L3 and SEMA3F. Additionally, our PCA data indicated several genes associated with different pathologic stages, including SNRPA and SNRPD2. Compared with adjacent normal tissues, we observed a highly expressed level of GAS2L3, SNRPA, and SNRPD2 (P = 0.002) genes in HCC tissues of our HLivH060PG02 cohort. We also detected the high expression pattern of GAS2L3, SEMA3F, SNRPA, and SNRPD2 in the datasets of GSE102079, GSE76427, GSE64041, GSE121248, GSE84005, and the qPCR assay using diethylnitrosamine-induced HCC mouse model. Moreover, SEMA3F and SNRPD2 protein were highly stained in the HCC tissues of the HPA database. The high expression level of these four genes was associated with the poor survival prognosis of HCC cases.

CONCLUSIONS

Our study provides evidence regarding the gene expression and mutational profile in different clinical pathologic stages of TCGA HCC cases. Identifying four targeting genes, including GAS2L3, SNRPA, SNRPD2, and SEMA3F, offers insight into the molecular mechanisms associated with different prognoses of HCC.

Long Noncoding RNA UCA1 in Gastrointestinal Cancers: Molecular Regulatory Roles and Patterns, Mechanisms, and Interactions

The rising trend of gastrointestinal (GI) cancer has become a global burden due to its aggressive nature and poor prognosis. Long noncoding RNAs (lncRNAs) have recently been reported to be overexpressed in different GI cancers and may contribute to cancer progression and chemoresistance. They are featured with more than 200 nucleotides, commonly polyadenylated, and lacking an open reading frame. LncRNAs, particularly urothelial carcinoma-associated 1 (UCA1), are oncogenes involved in regulating cancer progression, such as cell proliferation, invasion, migration, and chemoresistance, particularly in GI cancer. This review was aimed to present an updated focus on the molecular regulatory roles and patterns of lncRNA UCA1 in progression and chemoresistance of different GI cancers, as well as deciphering the underlying mechanisms and its interactions with key molecules involved, together with a brief presentation on its diagnostic and prognostic values. The regulatory roles of lncRNA UCA1 are implicated in esophageal cancer, gastric cancer, pancreatic cancer, hepatobiliary cancer, and colorectal cancer, where they shared similar molecular mechanisms in regulating cancer phenotypes and chemoresistance. Comparatively, gastric cancer is the most intensively studied type in GI cancer. LncRNA UCA1 is implicated in biological roles of different GI cancers via interactions with various molecules, particularly microRNAs, and signaling pathways. In conclusion, lncRNA UCA1 is a potential molecular target for GI cancer, which may lead to the development of a novel chemotherapeutic agent. Hence, it also acts as a potential diagnostic and prognostic marker for GI cancer patients.

Regulatory role of long non-coding RNA UCA1 in signaling pathways and its clinical applications

Long non-coding RNA metastasis-associated urothelial carcinoma associated 1 (UCA1) plays a pivotal role in various human diseases. Its gene expression is regulated by several factors, including transcription factors, chromatin remodeling and epigenetic modification. UCA1 is involved in the regulation of the PI3K/AKT, Wnt/β-catenin, MAPK, NF-κB and JAK/STAT signaling pathways, affecting a series of cellular biological functions, such as cell proliferation, apoptosis, migration, invasion and tumor drug resistance. Furthermore, UCA1 is used as a novel potential biomarker for disease diagnosis and prognosis, as well as a target for clinical gene therapy. The present review systematically summarizes and elucidates the mechanisms of upstream transcriptional regulation of UCA1, the regulatory role of UCA1 in multiple signaling pathways in the occurrence and development of several diseases, and its potential applications in clinical treatment.

SND1 promotes Th1/17 immunity against chlamydial lung infection through enhancing dendritic cell function

To date, no reports have linked the multifunctional protein, staphylococcal nuclease domain-containing protein 1 (SND1), to host defense against intracellular infections. In this study, we investigated the role and mechanisms of SND1, by using SND1 knockout (SND1-/-) mice, in host defense against the lung infection of Chlamydia muridarum, an obligate intracellular bacterium. Our data showed that SND1-/- mice exhibited significantly greater body weight loss, higher organism growth, and more severe pathological changes compared with wild-type mice following the infection. Further analysis showed significantly reduced Chlamydia-specific Th1/17 immune responses in SND1-/- mice after infection. Interestingly, the dendritic cells (DCs) isolated from SND1-/- mice showed lower costimulatory molecules expression and IL-12 production, but higher IL-10 production compared with those from wild-type control mice. In the DC-T cell co-culture system, DCs isolated from SND1-/- infected mice showed significantly reduced ability to promote Chlamydia-specific IFN-γ producing Th1 cells but enhanced capacity to induce CD4+T cells into Foxp3+ Treg cells. Adoptive transfer of DCs isolated from SND1-/- mice, unlike those from wild-type control mice, failed to protect the recipients against challenge infection. These findings provide in vivo evidence that SND1 plays an important role in host defense against intracellular bacterial infection, and suggest that SND1 can promote Th1/17 immunity and inhibit the expansion of Treg cells through modulation of the function of DCs.

miRNA-296-5p functions as a potential tumor suppressor in human osteosarcoma by targeting SND1

Background:

The pathogenesis of osteosarcoma (OS) is still unclear, and it is still necessary to find new targets and drugs for anti-OS. This study aimed to investigate the role and mechanism of the anti-OS effects of miR-296-5p.

Methods:

We measured the expression of miR-296-5p in human OS cell lines and tissues. The effect of miR-296-5p and its target gene staphylococcal nuclease and tudor domain containing 1 on proliferation, migration, and invasion of human OS lines was examined. The Student's t test was used for statistical analysis.

Results:

We found that microRNA (miR)-296-5p was significantly downregulated in OS cell lines and tissues (control vs. OS, 1.802 ± 0.313 vs. 0.618 ± 0.235, t = 6.402, P < 0.01). Overexpression of miR-296-5p suppressed proliferation, migration, and invasion of OA cells. SND1 was identified as a target of miR-296-5p by bioinformatic analysis and dual-luciferase reporter assay. Overexpression of SND1 abrogated the effects induced by miR-296-5p upregulation (miRNA-296-5p vs. miRNA-296-5p + SND1, 0.294 ± 0.159 vs. 2.300 ± 0.277, t = 12.68, P = 0.003).

Conclusion:

Our study indicates that miR-296-5p may function as a tumor suppressor by targeting SND1 in OS.

The Role of the PRMT5-SND1 Axis in Hepatocellular Carcinoma

Arginine methylation is an essential post-translational modification (PTM) deposited by protein arginine methyltransferases (PRMTs) and recognized by Tudor domain-containing proteins. Of the nine mammalian PRMTs, PRMT5 is the primary enzyme responsible for the deposition of symmetric arginine methylation marks in cells. The staphylococcal nuclease and Tudor domain-containing 1 (SND1) effector protein is a key reader of the marks deposited by PRMT5. Both PRMT5 and SND1 are broadly expressed and their deregulation is reported to be associated with a range of disease phenotypes, including cancer. Hepatocellular carcinoma (HCC) is an example of a cancer type that often displays elevated PRMT5 and SND1 levels, and there is evidence that hyperactivation of this axis is oncogenic. Importantly, this pathway can be tempered with small-molecule inhibitors that target PRMT5, offering a therapeutic node for cancer, such as HCC, that display high PRMT5–SND1 axis activity. Here we summarize the known activities of this writer–reader pair, with a focus on their biological roles in HCC. This will help establish a foundation for treating HCC with PRMT5 inhibitors and also identify potential biomarkers that could predict sensitivity to this type of therapy.

LncRNA UCA1 Affects the Cell Proliferation, Migration, Invasion and Apoptosis of Hepatic Carcinoma Cells by Targeting MicroRNA-193a-3p

OBJECTIVE/BACKGROUND

Hepatic carcinoma (HCC) is the fourth lethal cancer in the world, but its relationship with lncRNA urothelial cancer-associated 1 (UCA1)/microRNA-193a-3p axis remains unclear, so this study would explore the relationship.

METHODS

A real-time polymerase chain reaction (RT-PCR) assay was carried out to quantify lncRNA UCA1 and microRNA-193a-3p in HCC tissues and cells, and relevant overexpression or inhibition vectors were constructed to analyze the influences of lncRNA UCA1 and microRNA-193a-3p on HCC cells. A Transwell assay was used to measure invasion and migration of HCC cells, and a Western blot assay to quantify protein biomarkers of apoptosis, invasion, and migration, a MTT assay to determine cell viability, a flow cytometry to detect cell cycle, and a dual-luciferase reporter gene assay to analyze the correlation between lncRNA UCA1 and microRNA-193a-3p.

RESULTS

LncRNA UCA1 was increased in HCC, while microRNA-193a-3p was decreased. Down-regulated lncRNA UCA1 could up-regulate microRNA-193a-3p, and down-regulated lncRNA UCA1 or up-regulated microRNA-193a-3p would strengthen cell apoptosis and weaken cell migration, invasion, and proliferation. Furthermore, lncRNA UCA1 could negatively regulate microRNA-193a-3p by binding to it.

CONCLUSION

LncRNA UCA1 promotes malignant hyperproliferation of HCC cells by repressing microRNA-193a-3p.

A pan-cancer analysis of the oncogenic role of staphylococcal nuclease domain-containing protein 1 (SND1) in human tumors

Although emerging cell- or animal-based evidence supports the relationship between SND1 and cancers, no pan-cancer analysis is available. We thus first explored the potential oncogenic roles of SND1 across thirty-three tumors based on the datasets of TCGA (The cancer genome atlas) and GEO (Gene expression omnibus). SND1 is highly expressed in most cancers, and distinct associations exist between SND1 expression and prognosis of tumor patients. We observed an enhanced phosphorylation level of S426 in several tumors, such as breast cancer or lung adenocarcinoma. SND1 expression was associated with the CD8⁺T-cell infiltration level in colon adenocarcinoma and melanoma, and cancer-associated fibroblast infiltration was observed in other tumors, such as bladder urothelial carcinoma or testicular germ cell tumors. Moreover, protein processing- and RNA metabolism-associated functions were involved in the functional mechanisms of SND1. Our first pan-cancer study offers a relatively comprehensive understanding of the oncogenic roles of SND1 across different tumors.

Oncoprotein SND1 hijacks nascent MHC-I heavy chain to ER-associated degradation, leading to impaired CD8+ T cell response in tumor

SND1 is highly expressed in various cancers. Here, we identify oncoprotein SND1 as a previously unidentified endoplasmic reticulum (ER) membrane-associated protein. The amino-terminal peptide of SND1 predominantly associates with SEC61A, which anchors on ER membrane. The SN domain of SND1 catches and guides the nascent synthesized heavy chain (HC) of MHC-I to ER-associated degradation (ERAD), hindering the normal assembly of MHC-I in the ER lumen. In mice model bearing tumors, especially in transgenic OT-I mice, deletion of SND1 promotes the presentation of MHC-I in both B16F10 and MC38 cells, and the infiltration of CD8+ T cells is notably increased in tumor tissue. It was further confirmed that SND1 impaired tumor antigen presentation to cytotoxic CD8+ T cells both in vivo and in vitro. These findings reveal SND1 as a novel ER-associated protein facilitating immune evasion of tumor cells through redirecting HC to ERAD pathway that consequently interrupts antigen presentation.

LncRNA LINC00665 Promotes Prostate Cancer Progression via miR-1224-5p/SND1 Axis

Background

Increasing researches have revealed a critical role of long noncoding RNAs (lncRNAs) in tumor progression. LINC00665 is a poorly investigated lncRNA. In this research, we sought to determine the potential role of LINC00665 in prostate cancer (PC) progression.

Methods

LINC00665 expression was analyzed by bioinformatics method and qRT-PCR. Proliferation was determined via CCK8 and colony formation assays. Transwell assay was conducted to analyze migration and invasion. Xenograft assay was used to test the roles of LINC00665 in vivo. Luciferase reporter assay, pulldown assay and RIP assay were utilized to confirm the interaction between LINC00665 and miR-1224-5p.

Results

LINC00665 expression was increased in PC samples in contrast to control tissues, according to bioinformatics analysis and qRT-PCR validation. LINC00665 high expression was related to a poor prognosis. LINC00665 knockdown markedly attenuated growth and metastasis of PC cells and impaired tumor propagation in vivo. Mechanistic investigation revealed that LINC00665 was the sponge for miR-1224-5p. By inhibiting miR-1224-5p level, LINC00665 dramatically promoted the expression of SND1 in PC cells. Ectopic expression of SND1 significantly rescued the effects of LINC00665 silencing.

Conclusion

LINC00665 is a novel oncogenic gene in PC by targeting miR-1224-5p/SND1 pathway and may be a therapeutic target.

Effect of lncRNA‑BC200 on proliferation and migration of liver cancer cells in vitro and in vivo

In recent years, the important role of long non‑​coding RNAs (lncRNAs) in the development of liver cancer has received increasing attention. The abnormal expression level of long non‑coding RNAs has been associated with the occurrence and development of liver cancer. However, the role and molecular mechanisms of lncRNAs in the development and progression of liver cancer are not fully understood. The present study aimed to clarify the function and molecular mechanism of lncRNA brain cytoplasmic 200 (BC200) in liver cancer. In the present study, it was found that BC200 expression level was higher in hepatocellular carcinoma (HCC) tissues than that in adjacent tissues. Cell function was examined by constructing BC200 knockout (KO) and BC200‑overexpression in vitro models. It was found that BC200 affected the proliferation and migration of HepG2 cells. Interestingly, it was found that BC200 affected the expression of c‑Myc protein but did not affect the mRNA expression level of c‑MYC. BC200 KO cells exhibited a reduced protein expression level of Bax protein and an increased protein expression level of Bcl‑xL. Conversely, BC200 overexpression reduced the expression of Bcl‑xL protein and increased the expression of Bax protein. Importantly, it was found that BC200 affected the formation of subcutaneous tumors in nude mice. In conclusion, the present results suggested that lncRNA BC200 may play an important role in liver cancer.

The Oncogene PIM1 Contributes to Cellular Senescence by Phosphorylating Staphylococcal Nuclease Domain-Containing Protein 1 (SND1)

Background

The oncogene PIM1, encoding a constitutively active serine/threonine protein kinase, is involved in the regulation of cell proliferation, survival, differentiation, and apoptosis. There is a growing body of literature on the role of PIM1-mediated cellular senescence, but the precise mechanism remains unclear.

Material/Methods

Silver staining and LC–MS/MS analysis were performed to investigate the protein interacting with PIM1. Immunofluorescence, Co-IP, and Western blot assay were used to assess the interaction of PIM1 and SND1. EdU incorporation and CCK8 assay were used to detect cell proliferation and immunohistochemistry was used to detect the level of the indicated protein.

Results

We found that PIM1 can bind directly and phosphorylate SND1. In addition, decreased expression of SND1 leads to the upregulation of SASP. SND1 is involved in cellular senescence induced by PIM1.

Conclusions

We investigated the role of PIM1 in oncogene-induced normal cellular senescence. Our results promote further understanding of the mechanisms underlying OIS and suggest potential applications for preventing tumorigenesis.

Splicing Machinery is Dysregulated in Pituitary Neuroendocrine Tumors and is Associated with Aggressiveness Features

Pituitary neuroendocrine tumors (PitNETs) constitute approximately 15% of all brain tumors, and most have a sporadic origin. Recent studies suggest that altered alternative splicing and, consequently, appearance of aberrant splicing variants, is a common feature of most tumor pathologies. Moreover, spliceosome is considered an attractive therapeutic target in tumor pathologies, and the inhibition of SF3B1 (e.g., using pladienolide-B) has been shown to exert antitumor effects. Therefore, we aimed to analyze the expression levels of selected splicing-machinery components in 261 PitNETs (somatotropinomas/non-functioning PitNETS/corticotropinomas/prolactinomas) and evaluated the direct effects of pladienolide-B in cell proliferation/viability/hormone secretion in human PitNETs cell cultures and pituitary cell lines (AtT-20/GH3). Results revealed a severe dysregulation of splicing-machinery components in all the PitNET subtypes compared to normal pituitaries and a unique fingerprint of splicing-machinery components that accurately discriminate between normal and tumor tissue in each PitNET subtype. Moreover, expression of specific components was associated with key clinical parameters. Interestingly, certain components were commonly dysregulated throughout all PitNET subtypes. Finally, pladienolide-B reduced cell proliferation/viability/hormone secretion in PitNET cell cultures and cell lines. Altogether, our data demonstrate a drastic dysregulation of the splicing-machinery in PitNETs that might be associated to their tumorigenesis, paving the way to explore the use of specific splicing-machinery components as novel diagnostic/prognostic and therapeutic targets in PitNETs.

Cancer-related long noncoding RNAs show aberrant expression profiles and competing endogenous RNA potential in esophageal adenocarcinoma

Long non-coding RNAs (lncRNAs) govern gene expression by competitively binding to microRNA response elements (MREs). Although they were initially considered as transcriptional noise, lncRNAs have attracted increased attention in oncology. Dysregulation of lncRNAs occurs in various types of human tumor, including esophageal adenocarcinoma (EAC). However, the functions of these cancer-associated lncRNAs and of their related competitive endogenous RNA (ceRNA) network in EAC remains unknown. To determine the relevant potential mechanisms, the present study analyzed the transcriptome sequencing data and clinical information of 79 patients with EAC, including 79 tumor samples and 11 normal samples, which were obtained from The Cancer Genome Atlas esophageal cancer project. The edgeR v3.25.0 software was used for differential gene expression analysis. The results exhibited 561 cancer-associated lncRNAs with a >2.0-fold change and a false discovery rate-adjusted P<0.01. Among these lncRNAs, 26 were significantly associated with patient overall survival. According to data from bioinformatics databases and differentially expressed RNAs, an lncRNA-regulated ceRNA network for EAC was constructed. The results demonstrated that the aberrantly expressed lncRNA-associated ceRNA network included 37 EAC cancer-associated lncRNAs, five miRNAs and 13 mRNAs. In conclusion, the present study identified novel lncRNAs as candidate prognostic biomarkers and revealed a potential regulatory network of gene expression in EAC.

Long non-coding RNA SNHG5 promotes glioma progression via miR-205/E2F3 axis

In recent years, many studies have reported on the abnormal expression and correlation of long non-coding RNAs (lncRNAs) in tumours. However, the accurate molecular mechanism of lncRNAs in glioma is still in its infancy. In the present study, we aimed to explore the molecular mechanism of small nucleolar RNA host gene 5 (SNHG5) in glioma progression. First, we found that SNHG5 expression was higher in glioma and was related to glioma glucose uptake, migration and invasion. Second, through a series of assays, we concluded that SNHG5 acts as a sponge for miR-205, which inhibits tumour growth in glioma by targeting E2F transcription factor 3 (E2F3). Third, using a xenograft mouse model, we demonstrated that SNHG5 regulates tumourigenesis in vivo. Taken together, our results show that the SNHG5/miR-205/E2F3 axis is involved in glioma progression and may provide a new therapeutic target for the diagnosis and therapy of glioma.

Gene expression profiling analysis to investigate the role of remote ischemic postconditioning in ischemia-reperfusion injury in rats

Background

Blood flow restoration is a definitive therapy for salvaging the myocardium following ischemic injury. Nevertheless, the sudden restoration of blood flow to the ischemic myocardium can induce ischemia-reperfusion injury (IRI).

Results

Herein, we investigated the cardioprotective effect of remote ischemic postconditioning (RPostC) through our in vivo rat model of myocardial IRI. The study included three groups: the control group, the IRI group, and the IRI + RPostC group. Ischemia-reperfusion treatment led to an increase in the myocardial infarction area, which was inhibited by RPostC. In contrast to that in the control group, the myocardial apoptosis level was enhanced in the IRI group, whereas RPostC treatment decreased IRI-induced cellular apoptosis. Affymetrix Rat Gene 2.0 ST chip data identified a total of 265 upregulated genes and 267 downregulated genes between the IRI and IRI + RPostC groups. A group of differentially expressed noncoding RNAs (ncRNAs), such as MTA_TC0600002772.mm, MTA_TC1300002394.mm, U7 small nuclear RNA (Rnu7) and RGD7543256_1, were identified. Gene Ontology (GO) enrichment analysis indicated that the positive regulation of some molecular functions, such as GTPase activity, GTP binding, cyclic-nucleotide phosphodiesterase activity and cytokine activity, may contribute to the cardioprotective role of RPostC. Moreover, pathway enrichment analysis using the Kyoto Encyclopedia of Genes and Genomes (KEGG) suggested the potential implication of the TNF signaling pathway and Toll-like receptor signaling pathway. Global signal transduction network analysis, co-expression network analysis and quantitative real-time polymerase chain reaction analysis further identified several core genes, including Pdgfra, Stat1, Lifr and Stfa3.

Conclusion

Remote ischemic postconditioning treatment can decrease IRI-mediated myocardial apoptosis by regulating multiple processes and pathways, such as GTPase activity, cytokine activity, and the TNF and Toll-like receptor signaling pathways. The potential role of the above ncRNAs and core genes in IRI-induced cardiac damage merits further study as well.

Electronic supplementary material

The online version of this article (10.1186/s12864-019-5743-9) contains supplementary material, which is available to authorized users.

Insights Into SND1 Oncogene Promoter Regulation

The staphylococcal nuclease and Tudor domain containing 1 gene (SND1), also known as Tudor-SN, TSN or p100, encodes an evolutionarily conserved protein with invariant domain composition. SND1 contains four repeated staphylococcal nuclease domains and a single Tudor domain, which confer it endonuclease activity and extraordinary capacity for interacting with nucleic acids, individual proteins and protein complexes. Originally described as a transcriptional coactivator, SND1 plays fundamental roles in the regulation of gene expression, including RNA splicing, interference, stability, and editing, as well as in the regulation of protein and lipid homeostasis. Recently, SND1 has gained attention as a potential disease biomarker due to its positive correlation with cancer progression and metastatic spread. Such functional diversity of SND1 marks this gene as interesting for further analysis in relation with the multiple levels of regulation of SND1 protein production. In this review, we summarize the SND1 genomic region and promoter architecture, the set of transcription factors that can bind the proximal promoter, and the evidence supporting transactivation of SND1 promoter by a number of signal transduction pathways operating in different cell types and conditions. Unraveling the mechanisms responsible for SND1 promoter regulation is of utmost interest to decipher the SND1 contribution in the realm of both normal and abnormal physiology.