Pan-cancer analyses reveal genomics and clinical characteristics of the melatonergic regulators in cancer.

Melatonin, an endogenous hormone, plays protective roles in cancer. In addition to regulating circadian rhythms, sleep, and neuroendocrine activity, melatonin functions in various survival pathways. However, the mechanisms of melatonin regulation in cancer remain unknown. In the present study, we performed a comprehensive characterization of melatonin regulators in 9125 tumor samples across 33 cancer types using multi-omic data from The Cancer Genome Atlas and Cancer Cell Line Encyclopedia. In the genomic landscape, we identified the heterozygous amplification of AANAT and GPR50, and heterozygous deletion of PER3, CYP2C19, and MTNR1A as the dominant alteration events. Expression analysis revealed methylation-mediated downregulation of melatonergic regulator expression. In addition, we found that melatonergic regulator expression could be used to predict patient survival in various cancers. In depth, microRNA (miRNA) analysis revealed an miRNA-mRNA interaction network, and the deregulated miRNAs were involved in melatonin secretion and metabolism by targeting circadian clock genes. Pathway analysis showed that melatonergic regulators were associated with inhibition of apoptosis, the cell cycle, the DNA damage response, and activation of RAS/MAPK and RTK signaling pathways. Importantly, by mining the Genomics of Drug Sensitivity in Cancer database, we discovered a number of potential drugs that might target melatonergic regulators. In summary, this study revealed the genomic alteration and clinical characteristics of melatonergic regulators across 33 cancers, which might clarify the relationship between melatonin and tumorigenesis. Our findings also might provide a novel approach for the clinical treatment of cancers.

LncRNA-135528 inhibits tumor progression by up-regulating CXCL10 through the JAK/STAT pathway.

Spontaneous tumor regression can be observed in many tumors, however, studies related to the altered expression of lncRNA in spontaneous glioma regression are limited, and the potential contributions of lncRNAs to spontaneous glioma regression remain unknown. To investigate the biological roles of lncRNA-135528 in spontaneous glioma regression. The cDNA fragment of lncRNA-135528 was obtained by rapid-amplification of cDNA ends (RACE) technology and cloned into the plvx-mcmv-zsgreen-puro vector. Additionally, we stably silenced or overexpressed lncRNA-135528 in G422 cells by transfecting with siRNA against lncRNA-135528 or lncRNA-135528 overexpression plasmid. Then, we examined lncRNA-135528 overexpressing and lncRNA-135528 silencing on glioma cells and its effects on CXCL10 and JAK/STAT pathways. The main findings indicated that lncRNA-135528 promoted glioma cell apoptosis, inhibited cell proliferation and arrested cell cycle progression; the up-regulation of lncRNA135528 led to significantly increased CXCL10 levels and the differential expression of mRNA associated with JAK/STAT pathway in glioma cells. lncRNA-135528 can inhibit tumor progression by up-regulating CXCL10 through the JAK/STAT pathway.

Protective effect of Gelofusine against cRGD-siRNA-induced nephrotoxicity in mice.

Based on successful targeting to the αvß3 integrin of cyclic arginine-glycine-aspartic acid (cRGD), cRGD-conjugated small interfering RNA (siRNA) exhibits tumor targeting and has become a new treatment strategy for solid tumors. However, the nephrotoxicity caused by its renal retention limits its clinical application. Here, we evaluated the protective effect of Gelofusine against cRGD-conjugated siRNA-induced nephrotoxicity in mice. Male Kunming mice (six per group) were either co-injected with Gelofusine and cRGD-siRNA or injected with cRGD-siRNA alone. After administration of these treatments five times, creatinine and blood urea nitrogen (BUN) levels were determined. Hematoxylin-eosin staining (HE staining) and transferase dUTP nick end labeling (TUNEL) analysis were used to compare the difference in renal damage between the groups. Additionally, fluorescence imaging was used to observe the distribution of cRGD-siRNA in vivo. The group co-injected with Gelofusine and cRGD-siRNA displayed lower creatinine and BUN levels than the cRGD-siRNA-alone group and showed less renal damage upon HE staining and TUNEL analysis. Gelofusine decreased the retention time and accelerated the elimination of cRGD-siRNA from the organs, as observed in the fluorescence images. These data indicate that Gelofusine significantly increased the excretion of cRGD-conjugated siRNA and reduced the associated renal damage.

Regulation of lncRNA expression.

Long non-coding RNAs (lncRNAs) are series of transcripts with important biological functions. Various diseases have been associated with aberrant expression of lncRNAs and the related dysregulation of mRNAs. In this review, we highlight the mechanisms of dynamic lncRNA expression. The chromatin state contributes to the low and specific expression of lncRNAs. The transcription of non-coding RNA genes is regulated by many core transcription factors applied to protein-coding genes. However, specific DNA sequences may allow their unsynchronized transcription with their location-associated mRNAs. Additionally, there are multiple mechanisms involved in the post-transcriptional regulation of lncRNAs. Among these, microRNAs might have indispensible regulatory effects on lncRNAs, based on recent discoveries.

Network pharmacology and experimental validation of effects of total saponins extracted from Abrus cantoniensis Hance on acetaminophen-induced liver injury.

ETHNOPHARMACOLOGICAL RELEVANCE: Abrus cantoniensis Hance (AC), an abrus cantoniensis herb, is a Chinese medicinal herb used for the treatment of hepatitis. Total saponins extracted from AC (ACS) are a compound of triterpenoid saponins, which have protective properties against both chemical and immunological liver injuries. Nevertheless, ACS has not been proven to have an influence on drug-induced liver injury (DILI). AIM OF THE STUDY: This study used network pharmacology and experiments to investigate the effects of ACS on acetaminophen (APAP)-induced liver injury. MATERIALS AND METHODS: The targets associated with ACS and DILI were obtained from online databases. Cytoscape software was utilized to construct a "compound-target" network. In addition, Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were used to analyze the related signaling pathways impacted by ACS. AutoDock Vina was utilized to evaluate the binding affinity between bioactive compounds and the key targets. To validate the findings of network pharmacology, in vitro and in vivo experiments were conducted. Cell viability assay, transaminase activity detection, immunofluorescence assay, immunohistochemistry staining, RT-qPCR, and western blotting were utilized to explore the effects of ACS. RESULTS: 25 active compounds and 217 targets of ACS were screened, of which 94 common targets were considered as potential targets for ACS treating APAP-induced liver injury. GO and KEGG analyses showed that the effects of ACS exert their effects on liver injury through suppressing inflammatory response, oxidative stress, and apoptosis. Molecular docking results demonstrated that core active compounds of ACS were successfully docked to core targets such as CASP3, BCL2L1, MAPK8, MAPK14, PTGS2, and NOS2. In vitro experiments showed that ACS effectively attenuated APAP-induced damage through suppressing transaminase activity and attenuating apoptosis. Furthermore, in vivo studies demonstrated that ACS alleviated pathological changes in APAP-treated mice and attenuated inflammatory response. Additionally, ACS downregulated the expression of iNOS, COX2, and Caspase-3, and upregulated the expression of Bcl-2. ACS also suppressed the MAPK signaling pathway. CONCLUSIONS: This study demonstrated that ACS is a hepatoprotective drug through the combination of network pharmacology and in vitro and in vivo experiments. The findings reveal that ACS effectively attenuate APAP-induced oxidative stress, apoptosis, and inflammation through inhibiting the MAPK signaling pathway. Consequently, this research offers novel evidence supporting the potential preventive efficacy of ACS.

Cancer-Associated Fibroblasts Promote Radioresistance of Breast Cancer Cells via the HGF/c-Met Signaling Pathway.

PURPOSE: Cancer-associated fibroblasts (CAFs) are an integral part of the tumor microenvironment (TME), which is involved in therapy resistance. This study aimed to investigate the role of CAFs in radiosensitivity of breast cancer cells. METHODS AND MATERIALS: The CAFs were isolated from the breast cancer tissues, and the conditioned medium was collected to culture breast cancer cells. Radiation-induced DNA damage was evaluated by immunofluorescence and western blotting. Cytokine array and enzyme-linked immunosorbent assay were performed to analyze the secretion of cytokines and growth factors. An in vitro clonogenic survival assay and in vivo xenograft mouse model were performed to determine the radiosensitivity of breast cancer cells. Finally, the expression of hepatocyte growth factor (HGF) and c-Met in the breast cancer tissues were detected by immunohistochemistry. RESULTS: The CAFs were found to secrete HGF to activate the c-Met signaling pathway, which induced epithelial-to-mesenchymal transition, growth, and radioresistance of breast cancer cells. Furthermore, radiation was observed to enhance HGF secretion by CAFs and increase c-Met expression in breast cancer cells, which led to HGF/c-Met signaling pathway activation. Moreover, radiation-induced tumor necrosis factor α (TNFα) secretion by breast cancer cells promoted CAF proliferation and HGF secretion. Additionally, HGF and c-Met high expression were associated with worse recurrence-free survival in patients with breast cancer who had received radiation therapy. CONCLUSIONS: The findings revealed that HGF and TNFα are critical for the crosstalk between breast cancer cells and CAFs in the TME and that the HGF/c-Met signaling pathway is a promising therapeutic target for radiosensitizing breast cancer.

Upregulated Long Non-coding RNA Lnc-MRPL39-2:1 Induces the Growth and Invasion of Nasopharyngeal Carcinoma by Binding to HuR and Stabilizing ß-Catenin mRNA.

Long non-coding RNAs (lncRNAs) have been to regulate tumor progression and therapy resistance through various molecular mechanisms. In this study, we investigated the role of lncRNAs in nasopharyngeal carcinoma (NPC) and the underlying mechanism. Using lncRNA arrays to analyze the lncRNA profiles of the NPC and para-tumor tissues, we detected the novel lnc-MRPL39-2:1, which was validated by in situ hybridization and by the 5' and 3' rapid amplification of the cDNA ends. Further, its role in NPC cell growth and metastasis was verified in vitro and in vivo. The researchers conducted the RNA pull-down assays, mass spectrometry (MS), dual-luciferase reporter assays, RNA immunoprecipitation (RIP) assays, and the MS2-RIP assays were then used to identify the lnc-MRPL39-2:1-interacting proteins and miRNAs. We found that lnc-MRPL39-2:1, which was highly expressed in in NPC tissues, was related to a poor prognosis in NPC patients. Furthermore, lnc-MRPL39-2:1 was shown to induce the growth and invasion of NPC by interacting directly with the Hu-antigen R (HuR) to upregulate ß-catenin expression both in vivo and in vitro. Lnc-MRPL39-2:1 expression was also suppressed by microRNA (miR)-329. Thus, these findings indicate that lnc-MRPL39-2:1 is essential in NPC tumorigenesis and metastasis and highlight its potential as a prognostic marker and therapeutic target for NPC.

Opportunities and challenges of hepatocellular carcinoma organoids for targeted drugs sensitivity screening.

Hepatocellular carcinoma is one of the malignancies worldwide with a high mortality rate and an increasing incidence. Molecular Targeted agents are its common first-line treatment. Organoid technology, as a cutting-edge technology, is gradually being applied in the development of therapeutic oncology. Organoid models can be used to perform sensitivity screening of targeted drugs to facilitate the development of innovative therapeutic agents for the treatment of hepatocellular carcinoma. The purpose of this review is to provide an overview of the opportunities and challenges of hepatocellular carcinoma organoids in targeted drug sensitivity testing as well as a future outlook.

Identification of Clinical and Tumor Microenvironment Characteristics of Hypoxia-Related Risk Signature in Lung Adenocarcinoma.

Background: Lung cancer is the leading cause of cancer-related death globally. Hypoxia can suppress the activation of the tumor microenvironment (TME), which contributes to distant metastasis. However, the role of hypoxia-mediated TME in predicting the diagnosis and prognosis of lung adenocarcinoma (LUAD) patients remains unclear. Methods: Both RNA and clinical data from the LUAD cohort were downloaded from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Both univariate and multivariate Cox regression analyses were used to further screen prognosis-related hypoxia gene clusters. Time-dependent receiver operation characteristic (ROC) curves were established to evaluate the predictive sensitivity and specificity of the hypoxia-related risk signature. The characterization of gene set enrichment analysis (GSEA) and TME immune cell infiltration were further explored to identify hypoxia-related immune infiltration. Results: Eight hypoxia-related genes (LDHA, DCN, PGK1, PFKP, FBP1, LOX, ENO3, and CXCR4) were identified and established to construct a hypoxia-related risk signature. The high-risk group showed a poor overall survival compared to that of the low-risk group in the TCGA and GSE68465 cohorts (p < 0.0001). The AUCs for 1-, 3-, and 5-year overall survival were 0.736 vs. 0.741, 0.656 vs. 0.737, and 0.628 vs. 0.649, respectively. The high-risk group was associated with immunosuppression in the TME. Conclusion: The hypoxia-related risk signature may represent an independent biomarker that can differentiate the characteristics of TME immune cell infiltration and predict the prognosis of LUAD.

Pan-Cancer Analysis of Genomic and Prognostic Characteristics Associated With Coronavirus Disease 2019 Regulators.

Background: Cancer patients are alleged to have poor coronavirus disease 2019 (COVID-19) outcomes. However, no systematic or comprehensive analyses of the role and mechanisms of COVID-19 receptor-related regulators in cancer are available. Methods: We comprehensively evaluated the genomic alterations and their clinical relevance of six COVID-19 receptor-related regulators [transmembrane serine protease 2 (TMPRSS2), angiotensinogen (AGT), angiotensin-converting enzyme 1 (ACE1), solute carrier family 6 member 19 (SLC6A19), angiotensin-converting enzyme 2 (ACE2), and angiotensin II receptor type 2 (AGTR2)] across a broad spectrum of solid tumors. RNA-seq data, single nucleotide variation data, copy number variation data, methylation data, and miRNA-mRNA interaction network data from The Cancer Genome Atlas (TCGA) of 33 solid tumors were analyzed. We assessed the sensitivities of drugs targeting COVID-19 receptor-related regulators, using information from the Cancer Therapeutics Response Portal database. Results: We found that there are widespread genetic alterations of COVID-19 regulators and that their expression levels were significantly correlated with the activity of cancer hallmark-related pathways. Moreover, COVID-19 receptor-related regulators may be used as prognostic biomarkers. By mining the genomics of drug sensitivities in cancer databases, we discovered a number of potential drugs that may target COVID-19 receptor-related regulators. Conclusion: This study revealed the genomic alterations and clinical characteristics of COVID-19 receptor-related regulators across 33 cancers, which may clarify the potential mechanism between COVID-19 receptor-related regulators and tumorigenesis and provide a novel approach for cancer treatments.

A bivalent cyclic RGD-siRNA conjugate enhances the antitumor effect of apatinib via co-inhibiting VEGFR2 in non-small cell lung cancer xenografts.

The vascular endothelial growth factor receptor 2 (VEGFR2) is considered to be a pivotal target for anti-tumor therapy against angiogenesis of non-small cell lung cancer (NSCLC). However, effective and low-toxicity targeted therapies to inhibit VEGFR2 are still lacking. Here, biRGD-siVEGFR2 conjugate comprising murine VEGFR2 siRNA and [cyclo(Arg-Gly-Asp-D-Phe-Lys)-Ahx]2-Glu-PEG-MAL (biRGD) peptide which selectively binds to integrin αvß3 receptors expressing on neovascularization endothelial cell was synthesized. The anti-tumor activity and renal toxicity of biRGD-siVEGFR2 or its combination therapy with low-dose apatinib were investigated on NSCLC xenografts. The immunogenicity of biRGD-siVEGFR2 was also evaluated in C57BL/6J mice. In vivo, intravenously injected biRGD-siVEGFR2 substantially inhibited NSCLC growth with a marked reduction of vessels and a down-regulation of VEGFR2 in tumor tissue. Furthermore, biRGD-siVEGFR2 in combination with low-dose apatinib achieved powerful anti-tumor effect with less nephrotoxicity compared with the regular dose of apatinib. Besides, no obvious immunogenicity of biRGD-siVEGFR2 was found. These findings demonstrate that biRGD-siVEGFR2 conjugate can be used as a new candidate for the treatment of NSCLC and its combination therapy with apatinib may also provide a novel strategy for cancer treatment in clinic.

TCGA and ESTIMATE data mining to identify potential prognostic biomarkers in HCC patients.

Hepatocellular carcinoma (HCC) is an aggressive form of cancer characterized by a high recurrence rate following resection. Studies have implicated stromal and immune cells, which form part of the tumor microenvironment, as significant contributors to the poor prognoses of HCC patients. In the present study, we first downloaded gene expression datasets for HCC patients from The Cancer Genome Atlas database and categorized the patients into low and high stromal or immune score groups. By comparing those groups, we identified differentially expressed genes significantly associated with HCC prognosis. The Gene Ontology database was then used to perform functional enrichment analysis, and the STRING network database was used to construct protein-protein interaction networks. Our results show that most of the differentially expressed genes were involved in immune processes and responses and the plasma membrane. Those results were then validated using another a dataset from a HCC cohort in the Gene Expression Omnibus database and in 10 pairs of HCC tumor tissue and adjacent nontumor tissue. These findings enabled us to identify several tumor microenvironment-related genes that associate with HCC prognosis, and some those appear to have the potential to serve as HCC biomarkers.

Melatonin reverses nasopharyngeal carcinoma cisplatin chemoresistance by inhibiting the Wnt/ß-catenin signaling pathway.

Cisplatin (DDP)-based concurrent chemo-radiotherapy is a standard approach to treat locoregionally advanced nasopharyngeal carcinoma (NPC). However, many patients eventually develop recurrence and/or distant metastasis due to chemoresistance. In this study, we aimed to elucidate the effects of melatonin on DDP chemoresistance in NPC cell lines in vitro and vivo, and we explored potential chemoresistance mechanisms. We found that DDP chemoresistance in NPC cells is mediated through the Wnt/ß-catenin signaling pathway. Melatonin not only reversed DDP chemoresistance, but also enhanced DDP antitumor activity by suppressing the nuclear translocation of ß-catenin, and reducing expression of Wnt/ß-catenin response genes in NPC cells. In vivo, combined treatment with DDP and melatonin reduced tumor burden to a greater extent than single drug-treatments in an orthotopic xenograft mouse model. Our findings provide novel evidence that melatonin inhibits the Wnt/ß-catenin pathway in NPC, and suggest that melatonin could be applied in combination with DDP to treat NPC.

[Small interfering RNA-mediated programmed cell death-ligand 1 silencing in human glioma cells enhances human CD8+ T lymphocyte cytotoxicity in vitro].

OBJECTIVE: To investigate the effect of small interfering RNA (siRNA)-mediated silencing of programmed cell deathligand 1 (PD-L1) in human glioma cells on the cytotoxicity of human CD8+T lymphocytes against the modified tumor cells. METHODS: A siRNA sequence targeting PD-L1 gene was designed and transfected into human glioma U87 MG cells via lipofectamine 2000, and the gene silencing effect was validated using RT-qPCR, Western blotting, and flow cytometry. The transfected cells were co-cultured with human CD8+T lymphocytes, and the apoptosis of the tumor cells was analyzed with flow cytometry. RESULTS: The siRNA sequence showed strong PD-L1 gene-silencing effect at both mRNA and protein levels in U87 MG cells. Compared with the control cells, the transfected U87 MG cells showed significantly increased vulnerability to the cytotoxicity of human CD8+T cells and an obvious reduction of proliferative activity in the co-culture (P < 0.05). CONCLUSIONS: Transfection of human glioma U87 MG cells with the specific siRNA targeting PD-L1 obviously enhances the toxicity of human T lymphocytes in the co-culture.

An Efficient Bivalent Cyclic RGD-PIK3CB siRNA Conjugate for Specific Targeted Therapy against Glioblastoma In Vitro and In Vivo.

The PI3K-AKT-mTOR-signaling pathway is frequently activated in glioblastoma (GBM). Inhibition of phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit beta (PIK3CB)/p110ß (a PI3K catalytic isoform) by RNAi substantially suppresses GBM growth with less toxicity to normal astrocytes. However, insufficient and non-specific small interfering RNA (siRNA) delivery may limit the efficacy of RNAi-based therapies against GBM. Here we prepared a novel methoxy-modified PIK3CB siRNA molecule (siPIK3CB) that was covalently conjugated to a [cyclo(Arg-Gly-Asp-D-Phe-Lys)-Ahx]2-Glu-PEG-MAL (biRGD) peptide, which selectively binds to integrin αvß3 receptors. The αvß3-positive U87MG cell line was selected as a representative for GBM. An orthotopic GBM xenograft model based on luciferase-expressing U87MG was established and validated in vivo to investigate bio-distribution and anti-tumor efficacy of biRGD-siPIK3CB. In vitro, biRGD-siPIK3CB specifically entered and silenced PIK3CB expression in GBM cells in an αvß3 receptor-dependent manner, thus inhibiting cell cycle progression and migration and enhancing apoptosis. In vivo, intravenously injected biRGD-siPIK3CB substantially slowed GBM growth and prolonged survival by reducing tumor viability with silencing PIK3CB expression. Furthermore, biRGD-siPIK3CB led to mild tubulointerstitial injury in the treatment of GBM without obvious hepatotoxicity, whereas co-infusion of Gelofusine obviously alleviated this injury without compromising anti-tumor efficacy. These findings revealed a great translational potential of biRGD-siPIK3CB conjugate as a novel molecule for GBM therapy.

Gelofusine Attenuates Tubulointerstitial Injury Induced by cRGD-Conjugated siRNA by Regulating the TLR3 Signaling Pathway.

Integrin αvß3, which is selectively targeted by cyclic arginine-glycine-aspartic acid (cRGD) peptides, is significantly upregulated in tumors. Previous studies showed that small interfering RNA (siRNA) modified with cRGD (cRGD-siRNA) could significantly inhibit tumor growth through RNAi with oncogene expression. However, cRGD-siRNA is partially reabsorbed and trapped in the kidneys, causing renal injury in an unpredictable manner. This study aimed to investigate the influence of Gelofusine on tubulointerstitial injury induced by cRGD-siRNA in vitro and in vivo. The effect of Gelofusine on the distribution of cRGD-siRNA in tumor-bearing nude mice and wild-type mice was also explored. We found that Gelofusine inhibited apoptosis and activation of the innate immune response of human tubular epithelial cells induced by cRGD-siRNA in vitro. In addition, co-injection of Gelofusine efficiently reduced renal retention of cRGD-siRNA without affecting its tumor targeting in vivo. Further in vivo studies indicated that Gelofusine significantly attenuated tubulointerstitial injury induced by cRGD-siRNA through regulating Toll-like receptor 3 (TLR3)-mediated activation of the nuclear factor κ B (NF-κB) and caspase-3 apoptotic pathway. In conclusion, Gelofusine, acting as a novel and effective renal protective agent, could form a compound preparation with siRNA drugs for future clinical applications.

A tumor-targeting cRGD-EGFR siRNA conjugate and its anti-tumor effect on glioblastoma in vitro and in vivo.

The epidermal growth factor receptor (EGFR) is an important anti-tumor target. The development of novel molecular-targeted anti-tumor drugs that can target the interior of tumor cells and specifically silence EGFR expression is valuable and promising. In this work, a promising anti-tumor conjugate comprising methoxy-modified EGFR siRNA and cyclic arginine-glycine-aspartic acid (cRGD) peptides, which selectively bind to αvß3 integrins, was synthesized and examined. To prepare cRGD-EGFR siRNA (cRGD-siEGFR), cRGD was covalently conjugated to the 5'-end of an siRNA sense strand using a thiol-maleimide linker. The cellular uptake and cytotoxicity of cRGD-siEGFR in vitro were tested using an αvß3-positive U87MG cell line. In vivo bio-distribution, anti-tumor activity, immunogenicity and toxicity were investigated in a nude mouse tumor model through repeated i.v. administration of cRGD-siEGFR (7 times over a 48 h interval). Analyses of in vitro data showed that cRGD-siEGFR silenced EGFR expression effectively, with high tumor targeting ability. Administration of cRGD-siEGFR to tumor-bearing nude mice led to significant inhibition of tumor growth, obvious reduction of EGFR expression and down-regulation of EGFR mRNA and protein in tumor tissue. Furthermore, serum biochemistry and pathological section evaluation did not indicate any serious toxicity of cRGD-siEGFR in vivo. cRGD-siEGFR is likely a promising candidate with high targeting ability, substantial anti-tumor effects and low toxicity in vitro and in vivo.

LncRNA-N1LR Enhances Neuroprotection Against Ischemic Stroke Probably by Inhibiting p53 Phosphorylation.

In recent years, long noncoding RNAs (lncRNAs) have been shown to have critical roles in a broad range of cell biological processes. However, the activities of lncRNAs during ischemic stroke remain largely unknown. In this study, we carried out a genome-wide lncRNA microarray analysis in rat brains with ischemia/reperfusion (I/R) injury. The results revealed the differential expression of a subset of lncRNAs. Through the construction of lncRNA-mRNA co-expression networks, we identified lncRNA-N1LR as a novel I/R-induced lncRNA. The functions of lncRNA-N1LR were assessed by silencing and overexpressing this lncRNA in vitro and in vivo. We found that lncRNA-N1LR enhanced cell cycle progression and cell proliferation, and inhibited apoptosis in N2a cells subjected to in vitro ischemia (oxygen-glucose deprivation/reoxygenation, OGD/R). Furthermore, we showed that lncRNA-N1LR reduced neuronal apoptosis and neural cell loss in I/R-induced mouse brains. Mechanistically, we discovered that lncRNA-N1LR promoted neuroprotection probably through the inhibition of p53 phosphorylation on serine 15 in a manner that was independent of its location-associated gene Nck1. In summary, our results indicated that lncRNA-N1LR promoted neuroprotection against ischemic stroke probably by inactivating p53. Thus, we propose that lncRNA-N1LR may serve as a potential target for therapeutic intervention following ischemic brain injury.

MicroRNA-29b inhibits TGF-ß1-induced fibrosis via regulation of the TGF-ß1/Smad pathway in primary human endometrial stromal cells.

Transforming growth factor (TGF)­ß1 has a key role in the regulation of fibrosis and organ dysfunction. During the pathogenesis and progression of vital organ fibrosis, the microRNA (miR)­29 family is irregularly downregulated and exogenous supplementation of miR­29b has a strong anti­fibrotic capacity. However, whether TGF­ß1 is able to provoke endometrial fibrosis, and the role of miR­29 in endometrial fibrosis remain unclear. In the present study, RT­qPCR, immunocytochemistry, western blot analysis, scanning electron microscopy, immunofluorescence staining, cell proliferation assay and flow cytometric analysis were employed. The results demonstrated that the expression levels of collagen, type 1, alpha 1 (COL1A1), α­smooth muscle actin (α­SMA) and phosphorylated (p)­Smad2/3 were increased, whereas miR­29b and maternally expressed gene 3 (MEG3) were decreased in primary endometrial stromal cells (ESCs) in response to TGF­ß1 stimulation, in a time and dose­dependent manner. Furthermore, overexpression of miR­29b markedly reduced the expression levels of COL1A1 and α­SMA, and decreased the expression and nuclear accumulation of p­Smad2/3. In addition, ectopic overexpression of miR­29b increased the expression levels of MEG3, inhibited myofibroblast­like cell proliferation and induced apoptosis. These findings indicated that miR­29b may have a significant anti­fibrotic role, and may attenuate TGF­ß1­induced fibrosis in ESCs. Therefore, exogenous miR­29b may serve as a potential therapeutic agent for the treatment of endometrial fibrosis.