计算机网络时代发展十分迅速,许多企业都加强了对数据处理与运算方面的研究,并对其广泛应用,为企业的决策发展提供意见.由此可见,数据信息的处理技术在各大企业有着可观的应用潜力.如今,需要处理的数据类型五花八门,传统的处理技术要满足如今的需求十分吃力,这时则需借助云计算技术或数据分析获得理想的结果.基于以上,文章围绕计算机大数据分析及云计算网络技术进行探讨.
网络入侵检测是否高效的关键在于算法.稳定的算法能够通过较少的特征数据对链接进行精确识别,从而实现提前预警.传统网络入侵行为检测耗时长、检测率低,导致网络安全受到严重威胁,因此基于贝叶斯分类算法(Bayesian Classifier,BC)设计了入侵检测系统架构.该系统改进了传统检测方法,能够精简并融合大量多源数据,随后通过自适应调整阈值实现统一分析与管理.结果表明,与传统检测相比,该系统具有较强的扩展性与分布性,检测结果准确度提升,检测过程消耗时间显著降低.
Aberrant methylation is a hallmark of hepatocellular carcinoma and plays an important role in tumor initiation and progression. However, the epigenome-wide methylation patterns of portal vein tumor thrombosis (PVTTs) have not been fully explored. Here, we performed epigenome-wide DNA methylation of adjacent normal tissues (ANTs), paired tumor tissues and paired PVTTs using an Infinium HumanMethylation450 array (n = 11) and conducted the Sequenom EpiTYPER assays to confirm the aberrantly methylated genes. MTS and apoptosis assay were used to assess the synergistic effect of two drugs on the HCC cell lines. We found the mean global methylation levels of HCC tissues and PVTTs were significantly lower than ANTs (P < 0.01). A total of 864 differentially methylated CpG sites annotated in 532 genes were identified between HCC tissues and paired PVTTs (|mean methylation difference|>10%, P < 0.005). The pathway analysis based on hypermethylated genes in PVTT tissues was interestingly enriched in regulation of actin cytoskeleton pathway (P = 4.48E−5). We found 23 genes whose methylation levels were gradually alternated in HCC tissues and PVTTs. Aberrant methylation status of TNFRSF10A, ZC3H3 and SLC9A3R2 were confirmed in a validation cohort (n = 48). The functional experiments demonstrated the combination of decitabine (DAC) and tumor necrosis factor-related apoptosis-inducing ligand (rh-TRAIL) could synergistically suppress the proliferation and induce apoptosis in SK-Hep-1 and Huh7 cell lines. Together, our findings indicated that DNA methylation plays an important role in the PVTT formation through regulating the metastasis-related pathways. The combination of DAC and rh-TRAIL might be a promising treatment strategy for HCC.
The aim of our study was to explore the relationship between the methylation status of the alpha-1A adrenergic receptor (ADRA1A) gene and hepatocellular carcinoma (HCC). We combined our in-house data-set with the Cancer Genome Atlas (TCGA) data-set to screen and identify the methylation status and expression of adrenergic receptor (AR) genes in HCC. Immunohistochemistry and western blot were performed to assess the expression of ADRA1A in HCC cell lines and tissues. We further evaluated the methylation levels of the ADRA1A promoter region in 160 HCC patients using the Sequenom MassARRAY® platform and investigated the association between methylation of ADRA1A and clinical characteristics. The expression levels of ADRA1A mRNA and protein were significantly decreased in HCC tissues. Compared with that in paired normal tissues, the mean methylation level of the ADRA1A promoter region was significantly increased in tumour tissues from 160 HCC patients (25.2% vs. 17.0%, P < 0.0001). We found that a DNA methyltransferase inhibitor (decitabine) could increase the expression of ADRA1A mRNA in HCC cell lines. Moreover, hypermethylation of the ADRA1A gene in HCC samples was associated with clinical characteristics, including alcohol intake (P = 0.0097) and alpha-fetoprotein (P = 0.0411). Receiver operator characteristic (ROC) curve analysis demonstrated that the mean methylation levels of ADRA1A could discriminate between HCC tissues and adjacent non-cancerous tissues (AUC = 0.700, P < 0.0001). mRNA sequencing indicated that the main enriched pathways were pathways in cancer, cytokine-cytokine receptor interaction and metabolic pathways (P < 0.01). ADRA1A gene hypermethylation might contribute to HCC initiation and is a promising biomarker for the diagnosis of HCC.
Tumor-associated macrophages (TAMs) are important in tumor microenvironments and are closely associated with cancer occurrence, metastasis and progression. Colony stimulating factor 1 receptor (CSF1R) serves a crucial role in TAM formation. Whether CSF1R expression is regulated by DNA methylation in hepatocellular carcinoma (HCC) has not been fully elucidated. In the current study, HCC and adjacent non-cancerous tissue (ANT) samples were collected from 160 patients with HCC. CSF1R methylation levels were analyzed using a Mass ARRAY Analyzer to establish the potential impact of CSF1R methylation alternations on HCC clinicopathological characteristics. The mean methylation level of the CSF1R promoter (chr 5:149492491-149492958) was demonstrated to be significantly higher in ANTs compared with HCC tissues (65.3±7.5% vs. 57.3±14.4%, respectively; P<0.0001). CSF1R also exhibited decreased expression in HCC tissues compared with ANTs (P=0.0026). However, CSF1R expression was negatively correlated with CSF1R methylation levels in ANTs (r>0.4; P<0.0001). Further analysis indicated that patients with diabetes exhibited lower methylation levels in ANTs compared with HCC tissues (P=0.0062). Furthermore, CSF1R hypomethylation in ANTs was associated with a larger number of tumors (P=0.0332), larger tumor size (P=0.0494) and higher tumor grade (P=0.0244). Therefore, methylation alternation of the CSF1R promoter region analyzed in the present study was a key regulatory mechanism on CSF1R expression and ANT hypomethylation indicated poor clinicopathological characteristics of HCC. CSF1R may be a potential immunological therapeutic target for HCC.
Hepatocellular carcinoma (HCC) is a highly heterogeneous, multigene-driven malignant tumor. ZNF384 is an overexpressed gene with a high frequency of alteration in HCC, but research on the function of ZNF384 in HCC is lacking. In this study, the expression level of ZNF384 in HCC was analyzed through immunohistochemical (IHC) staining, Western blot analysis and qRT-PCR. We also generated ZNF384 knockdown and knockout HCC cell lines using short hairpin RNA (shRNA) and CRISPR/Cas9 systems. MTS, colony formation, and 5-ethynyl-20-deoxyuridine (EdU) assays; flow cytometry; and a xenograft mouse model were used to evaluate the effects of ZNF384 on cell proliferation. Western blot analysis, a dual luciferase reporter assay and a ChIP assay were performed to explore the potential mechanism. We found that overexpression of ZNF384 in HCC and elevated expression of ZNF384 in HCC tissues was significantly correlated with tumor recurrence ( P = 0.0097). Kaplan–Meier survival analysis revealed that high expression levels of ZNF384 were correlated with poor overall survival ( P = 0.0386). Downregulation of ZNF384 expression suppressed HCC cell proliferation by inhibiting the expression of Cyclin D1. These findings suggest that ZNF384 tends to act as an oncogene in the development of HCC. ZNF384 promotes the proliferation of HCC cells by directly upregulating the expression of Cyclin D1 and might serve as a prognostic predictive factor for HCC patients.
BACKGROUND:Small nucleolar RNAs (snoRNAs) function in guiding 2'-O-methylation and pseudouridylation of ribosomal RNAs (rRNAs) and small nuclear RNAs (snRNAs). In recent years, more and more snoRNAs have been found to play novel roles in mRNA regulation, such as pre-mRNA splicing or RNA editing. In our previous study, we found a silkworm C/D box snoRNA Bm-15 can interact with Notch receptor gene in vitro. To further study the function of Bm-15, we cloned its homolog Sf-15 from Spodoptera frugiperda and investigate the function of Sf-15 in Sf9 cells.RESULTS:We showed that knocking down of Sf-15 can inhibit the proliferation, then induce apoptosis of insect S. frugiperda Sf9 cells, but the results were reversed when Sf-15 was overexpressed. De novo sequencing of transcriptome of Sf9 cells showed that the expression of 21 apoptosis-related genes were increased upon Sf-15 repression. Further analysis showed that a Ca2+-induced cell death pathway gene Cn (PPP3C, the serine/threonine-protein phosphatase 2B catalytic subunit), was significantly increased upon Sf-15 depression but decreased when Sf-15 was overexpressed, which indicated that Cn might be a potential target of Sf-15.CONCLUSIONS:We conclude that C/D box snoRNA Sf-15 can participate in apoptosis through regulating the expression of Ca2+-induced cell death pathway gene Cn in Sf9 cells. This is the first time that we found snoRNAs exhibiting dual functions in insect, which reveals a novel layer of ncRNA modulation in cell growth and death.
Purpose: The aim of this study is to analyze the methylation levels of SPG20 promotor region and explore the association between the methylation levels and clinical features in hepatocellular carcinoma (HCC). Materials and methods: We collected paired of HCC and adjacent non-cancerous tissues (ANT) from 160 HCC patients and analyze the methylation levels through MassARRAY Analyzer 4. The statistical calculations were performed using SPSS version 22.0. Real-time-quantification PCR was performed to assess expression levels of SPG20 in HCC cell lines. Wound healing assay and transwell assay was used to measure cell migration capacity. Result: We found that mean methylation level of SPG20 in tumor tissues was significantly higher than that in ANT (7.3% vs. 16.2%, P<0.0013). There was a significantly negative correlation between expression level and methylation level of SPG20 (P<0.01). In addition, the methylation levels in HCC were correlated with age and HBV infection. Meanwhile, micro-satellite tumors (P=0.016) and tumor number (P=0.018) was found significantly associated with increased methylation levels of several CpG sites and the mean levels of SPG20 promotor in ANT. In addtion, the capacity of cell migration was significantly enhanced in SPG20 knock-down HCC cells. Conclusion: The hypermethylation status of SPG20 gene promoter is significantly associated with intra-hepatic metastasis and contribute to HCC metastasis.
[Aim]To study the interference efficiency of antisense oligonucleotide (ASO) with insect small nucleolar RNA (snoRNA) Bm-15, and to investigate the intracellular delivery of ASO in cells.[Methods]Spodoptera frugiperda Sf9 cells were transfected with Cy5-labeled, 2'-O ribosomal methylation and phosphorothioate-modified ASO of Bm-15 through liposome. Co-localization of Bm-15 ASO (labeled with Cy5) and lysosome as well as mitochondria was screened by immunofluorescence. The interference efficiency of ASO with snoRNA Bm-15 was analyzed by detecting the expression level of Bm-15 in Sf9 cells transfected with Bm-15 ASO using real-time PCR. [Results]The proportions of ASO fluorescence signals inundating the whole cell and at the cell edge were 34% and 66%, respectively, in the transfected Sf9 cells after 48 h transfection of Bm-15 ASO, suggesting that ASO might be delivered into different subcellular organelles. Further co-localization analysis showed that Bm-15 ASO was transportedinto lysosomes but not mitochondria. Qpcr result showed that the expression level of Bm-15 decreased by47% in Sf9 cells transfected with Bm-15 ASO. [Conclusion]ASO can not escape from the cellular endogenous degradation machinery even after various chemical modifications, and this effectively explains the low interference efficiency of ASO with target gene in some circumstances.