Circular RNA ATXN7 promotes the development of gastric cancer through sponging miR-4319 and regulating ENTPD4.
环状 RNA ATXN7 通过海绵 miR-4319 和调节 entpd4 促进胃癌的发展。
- 作者列表："Zhang Z","Wu H","Chen Z","Li G","Liu B
Background:Circular RNAs (circRNAs) which are shown as a class of RNAs exhibit the importance in the regulation of gene expression and the development of biological process. However, the expression profile and molecular mechanism of circRNA ATXN7 (circATXN7) is still mostly uncertain in gastric cancer (GC). Methods:qRT-PCR analysis was performed to detect the expression of circATXN7, miR-4319 and ENTPD4 in GC tissues and cells. CCK-8, colony formation, EdU, flow cytometry, TUNEL and transwell assays were conducted to assess the effect of circATXN7 or miR-4319 on cell proliferation, apoptosis and invasion. In vivo assays were utilized to further analyze the function of circATXN7 on the tumorigenesis and progression of GC. The interaction between miR-4319 and circATXN7 (or ENTPD4) was verified using luciferase reporter and RNA pull-down assays. Results:The results showed an upregulated circATXN7 expression in GC tissues and cell lines. Besides, silenced circATXN7 hampered the proliferation and invasion as well as promoted the apoptosis in GC cells. Moreover, low expression of miR-4319 was found in GC. It was determined that circATXN7 acted as a sponge for miR-4319 and had a negative association with miR-4319. We also found that miR-4319 upregulation restrained GC cell proliferation and migration whereas enhanced apoptosis. Subsequently, ENTPD4, the target gene of miR-4319, was found overexpressed in GC. Additionally, it was negatively correlated with miR-4319 whereas positively associated with circATXN7. In vivo experiments, circATXN7 silence was confirmed to inhibit GC tumor growth. Conclusions:CircATXN7 promoted GC development through sponging miR-4319 and regulating ENTPD4, which identified circATXN7 as a new biomarker in GC.
背景: 环状 rna (Circular RNAs，circRNAs) 被认为是一类 rna，在基因表达调控和生物过程的发生发展中具有重要意义。然而，circRNA ATXN7 (circATXN7) 的表达谱和分子机制在胃癌 (GC) 中仍大多不确定。 方法: 采用 qRT-PCR 方法检测胃癌组织和细胞中 circATXN7 、 miR-4319 和 ENTPD4 的表达。CCK-8 、集落形成、 EdU 、流式细胞术、 TUNEL 和 transwell 试验评估 circATXN7 或 miR-4319 对细胞增殖、凋亡和侵袭的影响。利用体内试验进一步分析 circATXN7 在 GC 肿瘤发生和进展中的功能。使用荧光素酶报告基因和 RNA 下拉分析验证 miR-4319 和 circATXN7 (或 ENTPD4) 之间的相互作用。 结果: 结果显示在 GC 组织和细胞系中 circATXN7 表达上调。此外，沉默的 circATXN7 抑制了 GC 细胞的增殖和侵袭，促进了细胞凋亡。此外，在 GC 中发现 miR-4319 低表达。确定 circATXN7 作为海绵 miR-4319，与 miR-4319 呈负相关。我们还发现 miR-4319 上调抑制了 GC 细胞的增殖和迁移，而增强了细胞凋亡。随后发现 miR-4319 的靶基因 ENTPD4 在 GC 中过表达。此外，它与 miR-4319 呈负相关，而与 circatxn7 呈正相关。体内实验证实 circATXN7 沉默可抑制 GC 肿瘤生长。 结论: CircATXN7 通过海绵化 miR-4319 和调控 ENTPD4 促进 GC 发育，这确定了 circATXN7 是 GC 中一个新的生物标志物。
METHODS::Diffuse gastric cancer (DGC) is a lethal malignancy lacking effective systemic therapy. Among the most provocative recent results in DGC has been that the alter of the cellular cytoskeleton and intercellular adhesion. CD2-associated protein (CD2AP) is one of the critical proteins regulating cytoskeleton assembly and intercellular adhesion. However, no study has investigated the expression and biological significance of CD2AP in gastric cancer (GC) to date. Therefore, the aim of our study was to explore if the expression of CD2AP is associated with any clinical features of GC and to elucidate the underlying mechanism. Immunohistochemistry of 620 patient tissue samples indicated that the expression of CD2AP is downregulated in DGC. Moreover, a low CD2AP level was indicative of poor patient prognosis. In vitro, forced expression of CD2AP caused a significant decrease in the migration and invasion of GC cells, whereas depletion of CD2AP had the opposite effect. Immunofluorescence analysis indicated that CD2AP promoted cellular adhesion and influenced cell cytoskeleton assembly via interaction with the F-actin capping protein CAPZA1. Overall, the upregulation of CD2AP could attenuate GC metastasis, suggesting CD2AP as a novel biomarker for the prognosis and treatment of patients with GC.
METHODS::Aim: To identify the methylated-differentially expressed genes (MDEGs) that may serve as diagnostic markers and therapeutic targets in Epstein-Barr virus-associated gastric cancer (EBVaGC) and to explore the methylation-based pathways for elucidating biological mechanisms of EBVaGC. Materials & methods: Gene expression and methylation profiles were downloaded from GEO database. MDEGs were identified by GEO2R. Pathway enrichment analyses were conducted based on DAVID database. Hub genes were identified by Cytoscape, which were further verified by The Cancer Genome Atlas database. Results: A total of 367 hypermethylated, lowly expressed genes were enriched in specific patterns of cell differentiation. 31 hypomethylated, highly expressed genes demonstrated enrichment in regulation of immune system process. After validation using The Cancer Genome Atlas database, seven genes were confirmed to be significantly different hub genes in EBVaGC. Conclusion: EBVaGC-specific MDEGs and pathways can be served as potential biomarkers for precise diagnosis and treatment of EBVaGC and provide novel insights into the mechanisms involved.
METHODS:Gastric adenocarcinoma, like other cancers, is a multifactorial genetic disease, andmetastasis of cancer cells is one of the main features of this illness. The expressionlevels of the CFL1 gene have been modulated in this pathway. Using small interferingRNA (siRNA) in the treatment of gastric cancer is considered a hopeful genetherapeutic approach. The present study reported the level of CFL1 genes betweentumor and margin and healthy tissue of gastric cancer. Also, the features of a cationicnanoparticle with a polymer coating containing polyacrylic acid and polyethylenei-mine that were used in the delivery of CFL1 siRNA, were shown. Then thecytotoxicity, cellular uptake, and gene silencing efficiency of this nanoparticle wereevaluated with CFL1siRNA. Method:In this study, the CFL1 gene expression was measured in 40 gastricadenocarcinoma, marginal and 15 healthy biopsy samples by a real‐time polymerasechain reaction. Physicochemical characteristics, apoptosis, and inhibition of migrationof the delivery of CFL1 siRNA by nanoparticle and lipofectamine were investigated ingastric cancer cells. Result:The CFL1 expression was remarkably increased in gastric cancer tissues incomparison with the marginal samples and normal tissues (p< .05) and the biomarkerindex for CFL1 was obtained as 0.94, then this gene can be probably used as abiomarker for gastric cancer. After treatment of the AGS cell line by CFL1 siRNA, theCFL1 expression level of mRNA and migration in AGS cells were remarkablysuppressed after transfection. Furthermore, the amount of apoptosis increased(p< .05). Conclusion:Our results demonstrated that CFL1 downregulation in AGS cells caninterdict cell migration. Finally, our outcomes propose that CFL1 can function as anoncogenic gene in gastric cancer and would be considered as a potential purpose ofgene therapy for gastric cancer treatment