Project description:BackgroundRecent evidence indicates that Kruppel-like factor 13 (KLF13) has critical roles in regulating cell differentiation, proliferation and may function as a tumor suppressor. However, its role in glioma progression is poorly understood.MethodsPublic database was used to explore the expression and prognostic value of KLF13 in glioma. Cell proliferation and invasion assays were used to explore the role of KLF13. Bisulfite sequencing and ChIP assay were used to determine the methylation of KLF13 promoter in glioma and the regulation of KLF13 by DNMT1.ResultsWe found that KLF13 inhibited glioma cell proliferation and invasion, which could be reversed by AKT activation. DNMT1-mediated hypermethylation was responsible for downregulation of KLF13. Knocking down of DNMT1 restored KFL13 expression and inhibited cell proliferation and invasion as well. Patients with high expression of KLF13 might have a better prognosis.ConclusionKLF13 suppressed glioma aggressiveness and the regulation of KLF13 could be a potential therapeutic target.
Project description:Gliomas are the most common and fatal brain tumors worldwide. Abnormal DNA promoter methylation is an important mechanism for gene loss of tumor suppressors. A long non-coding RNA colorectal adenocarcinoma hypermethylated (CAHM) has been reported to be nearly deleted in glioblastomas (GBMs). Nevertheless, the roles of CAHM in gliomas remain unknown up to now. In the present study, 969 glioma samples downloaded from the CGGA and Gravendeel databases were included. We found that CAHM expression was correlated with glioma grades, molecular subtype, IDH mutation status, and 1q/19p codel status. In glioma cells, CAHM is hypermethylated by DNA methyltransferase1 (DNMT1) and the loss of CAHM expression could be reversed by 5-Aza-2'-deoxycytidine (5-Aza), a specific inhibitor of DNA methyltransferases. Besides, the expression of CAHM was negatively associated with overall survival in both primary and recurrent gliomas. Moreover, the result of Gene Ontology (GO) analysis suggested that CAHM participated in negatively regulating cell development, nervous system development, neurogenesis, and integrin-mediated signaling pathway. Overexpression of CAHM inhibited glioma cell proliferation, clone formation, and invasion. Further exploring results showed that CAHM overexpression suppressed glioma migration and invasion through SPAK/MAPK pathway. Collectively, this study disclosed that CAHM might be a suppressor in gliomas.
Project description:BackgroundGlioma is the most lethal primary brain tumor, the survival rate still isn't improved in the past decades. It's essential to study the regulatory mechanism of glioma progression, hoping to find new therapy targets or methods. The family of tripartite motif (TRIM) containing proteins are E3 ubiquitination ligases, which play critical role in various tumor progression.MethodsCell proliferation and invasion were analyzed by colony formation assay, soft agar growth assay, BrdU incorporation assay and transwell invasion assay. Luciferase reporter analysis was used to analyze NF-κB pathway activity.ResultsWe found TRIM31 was upregulated in glioma cells and tissues, its overexpression significantly promoted glioma cell proliferation and invasion, while its knockdown significantly inhibited glioma cell proliferation and invasion. Mechanism analysis found TRIM31 promoted NF-κB pathway activity and increased its targets expression. NF-κB inhibition reversed the phenotype caused by TRIM31, confirming TRIM31 promoted glioma progression through activating NF-κB pathway. Using clinical specimens found TRIM31 expression was positively correlative with NF-κB activity.ConclusionThis study found TRIM31 promoted glioma proliferation and invasion through activating NF-κB activity.
Project description:Prostate cancer (PCa) is a heterogeneous tumor that commonly occurs among males worldwide. This study explored the potential role that long non-coding RNA MCM3AP antisense RNA 1 (MCM3AP-AS1) plays in PCa progression, and investigated its mechanism. MCM3AP-AS1 and neuropeptide Y receptor Y1 (NPY1R) expression was determined in PCa cells. The regulatory role of MCM3AP-AS1 in PCa cells was defined using scratch test, Transwell assay, 5-ethynyl-2'-deoxyuridine (EdU) assay, and flow cytometry. Methylation-specific PCR (MSP) was used to test the methylation level of NPY1R. Subsequently, the interaction among MCM3AP-AS1, DNA methyltransferase (DNMT)1/DNMT3 (A/B), and NPY1R was investigated using RNA immunoprecipitation, RNA pull-down, and chromatin immunoprecipitation. Finally, we observed xenograft tumor in nude mice. MCM3AP-AS1 was highly, whereas NPY1R was poorly, expressed in PCa. Lentivirus-mediated overexpression of MCM3AP-AS1 promoted proliferation, invasion, and migration while suppressing apoptosis of PCa cells, whereas opposite trends were detected after inhibition of the mitogen-activated protein kinase (MAPK) pathway. MCM3AP-AS1 promoted methylation of NPY1R promoter via recruitment of DNMT1/DNMT3 (A/B), thereby downregulating NPY1R expression to activate the MAPK pathway. Furthermore, overexpressed MCM3AP-AS1 was observed to facilitate PCa development in vivo, which could be reversed by overexpressed NPY1R. Altogether, MCM3AP-AS1 silencing inhibits PCa progression by disrupting methylation of the NPY1R promoter to inactivate the MAPK pathway.
Project description:Inheritance of epigenetic information encoded by cytosine DNA methylation patterns is crucial for mammalian cell survival, in large part through the activity of the maintenance DNA methyltransferase (DNMT1). Here, we show that SET7, a known histone methyltransferase, is involved in the regulation of protein stability of DNMT1. SET7 colocalizes and directly interacts with DNMT1 and specifically monomethylates Lys-142 of DNMT1. Methylated DNMT1 peaks during the S and G(2) phases of the cell cycle and is prone to proteasome-mediated degradation. Overexpression of SET7 leads to decreased DNMT1 levels, and siRNA-mediated knockdown of SET7 stabilizes DNMT1. These results demonstrate that signaling through SET7 represents a means of DNMT1 enzyme turnover.
Project description:Eukaryotic translation elongation factor 1δ (EEF1D), a subunit of the elongation factor 1 complex of proteins, mediates the elongation process of protein synthesis. Besides this canonical role, EEF1D was found overexpressed in many tumors, like hepatocarcinomas and medulloblastomas. In the present study, we demonstrated for the first time that EEF1D may interact with other putative proteins to regulate cell proliferation, migration, and invasion through PI3K/Akt and EMT pathways in glioma. Furthermore, knockdown of EEF1D could reduce cell proliferation and impaired epithelial-mesenchymal transition (EMT) phenotypes, including cell invasion. Taken together, these results indicate that EEF1D and its partner proteins might play a critical role in glioma and serve as a potential therapeutic target of glioma.
Project description:BackgroundThe carcinogenic effect of NUP37 has been reported recently in a variety of tumors, but its research in the field of glioma has not been paid attention. The main purpose of this study is to reveal the relationship between NUP37 and prognosis or clinical characteristics of glioma patients.MethodsFirst, as a retrospective study, this study included thousands of tissue samples based on a variety of public databases and clinicopathological tissues. Second, a series of bioinformatics analysis methods were used to analyze the NUP37 and glioma samples from multiple databases such as the CGGA, TCGA, GEO, HPA, and GEPIA. Third, to analyze the relationship between the expression level of NUP37 in tumor tissues and cells and a variety of clinical prognostic molecular characteristics, whether it can be an independent risk factor leading to poor prognosis in glioma and whether it has clinical diagnostic value; GSEA was used to analyze the cancer-related signaling pathways that may be activated by high expression of NUP37. Fifth, CMap was used to analyze small molecule drugs that may inhibit NUP37 expression. Finally, the meta-analysis of thousands of tissue samples from seven datasets and cell proliferation and migration experiments confirmed that NUP37 has a malignant effect on glioma.ResultsNUP37 is highly expressed in glioma patient tissues and glioma cells, significantly correlates with reduced overall survival, and may serve as an independent prognostic factor with some diagnostic value. Silencing NUP37 suppresses malignant biological behaviors of glioma cells. 4 small molecule drugs that had potential targeting inhibitory effects on NUP37 overexpression.ConclusionsThis study demonstrates for the first time a malignant role of NUP37 in glioma and provides a vision to unravel the complex pathological mechanisms of glioma and a potentially valuable biomarker for implementing individualized diagnosis and treatment of glioma.
Project description:GINS1 is a GINS complex subunit that functions along with the MCM2-7 complex and Cdc45 in eukaryotic DNA replication. Despite the significance of the GINS complex in the switch between quiescence and proliferation of glioma cells inside and outside the perinecrotic niche, the biological functions and the underlying mechanism of GINS1 remain unclear. Unlike in normal cells and tissues, GINS1 expression level was significantly upregulated in glioma cells and tissues. High expression of GINS1 predicted an advanced clinical grade and a poor survival. Functional assays revealed that GINS1 aggravated glioma malignant phenotypes in vitro and in vivo. Mechanistically, this study identified that GINS1 physically interacts with TOP2A. GINS1 promotes glioma cell proliferation and migration through USP15-mediated deubiquitination of TOP2A protein. Our results delineate the clinical significance of GINS1 in glioma and the regulatory mechanisms involved in glioma cell proliferation and migration. This work provides potential therapeutic targets for glioma treatment.
Project description:Chondroitin polymerizing factor (CHPF) is an important glycosyltransferases that participates in the biosynthesis of chondroitin sulfate (CS). Our previous study showed that silencing CHPF expression inhibited glioma cell proliferation in vitro, but the molecular mechanisms by which CHPF contributes to development of glioma have not been characterized. In this study, we found that CHPF was up-regulated in glioma tissues and was positively correlated with malignant clinical pathological characteristics of patients with glioma. Silencing CHPF expression inhibited proliferation, colony formation, migration, and cell cycle of glioma cells. Moreover, silencing CHPF suppressed glioma malignance in vivo. Immunoprecipitation, co-immunoprecipitation, GST pulldown, and liquid chromatography-mass spectrometry (LC-MS/MS) assays were used to verify the interaction between CHPF and Mitotic arrest deficient 1-like 1 (MAD1L1). In addition, Chromatin Immunoprecipitation (ChIP)-PCR analysis showed that HNF4A bound to the CHPF promoter region, which indicated that the transcription factor hepatocyte nuclear factor 4A (HNF4A) could regulate the expression of CHPF in glioma cells.
Project description:FBXO17 is a newly studied F-box protein associated with high-grade glioma. However, its exact role in glioma remains unclear. In the present study, we aimed to investigate the role of FBXO17 in glioma both in vitro and in vivo and explore the underlying mechanism. Our results showed that FBXO17 mRNA and protein levels were upregulated in glioma cells including U87, U251, SHG44, and U-118-MG cells as compared to the HA1800 cells. Downregulation of FBXO17 significantly suppressed the cellular behaviors of glioma cells including cell proliferation, migration, and invasion. In addition, FBXO17 knockdown induced E-cadherin expression and inhibited N-cadherin and vimentin expression at mRNA and protein levels in glioma cells. In contrast, overexpression of FBXO17 promoted cell proliferation, migration, invasion and EMT process. Furthermore, FBXO17 regulated the Akt/GSK-3β/snail signaling pathway in glioma cells with significant changes in the expression levels of p-Akt, p-GSK-3β and snail. Additionally, inhibition of Akt by LY294002 reversed the effects of FBXO17 overexpression on cellular behaviors of glioma cells. Finally, in vivo mouse xenograft assay proved that downregulation of FBXO17 suppresses the tumorigenesis of glioma. In conclusion, these findings demonstrated that FBXO17 acted as a promotor of glioma development via modulating Akt/GSK-3β/snail signaling pathway.