LncRNA TTN-AS1 drives invasion and migration of lung adenocarcinoma cells via modulation of miR-4677-3p/ZEB1 axis

Lung adenocarcinoma is the most prevalent type of lung cancer with a high incidence and mortality worldwide. Metastasis is the major cause of high death rate in lung cancer and the potential mechanism of lung adenocarcinoma metastasis remains indistinct. Emerging investigations have demonstrated that long noncoding RNA is a kind of non–protein coding RNA and plays a critical role in cancer progression and metastasis. TTN antisense RNA 1 (TTN-AS1) has been reported to promote cell growth and metastasis in cancer. However, the function of TTN-AS1 in lung adenocarcinoma is still to be illustrated. In this study, we observed that TTN-AS1 was upregulated in tissues and cells of lung adenocarcinoma and associated with poor overall survival. TTN-AS1 promoted cell proliferation, migration, invasion, and epithelial-mesenchymal transition in lung cancer. TTN-AS1 directly bound with miR-4677-3p and negatively regulated miR-4677-3p. MiR-4677-3p rescued the inhibitive impacts of TTN-AS1 knockdown on lung adenocarcinoma. Furthermore, zinc finger E-box binding homeobox 1 (ZEB1) was the target of miR-4677-3p, and TTN-AS1 modulated ZEB1 by competing for miR-4677-3p. TTN-AS1 drove the invasion and migration of lung adenocarcinoma cells by targeting the miR-4677-3p/ZEB1 axis. To sum up, our study offers insights into the mechanism of TTN-AS1 in lung adenocarcinoma metastasis and targeting the TTN-AS1/miR-4677-3p/ZEB1 axis may be the potential innovate therapeutic strategy for the patients with lung adenocarcinoma.     

CircRAPGEF5 Promotes the Proliferation and Metastasis of Lung Adenocarcinoma through the miR-1236-3p/ZEB1 Axis and Serves as a Potential Biomarker

Lung adenocarcinoma (LAD) is a common malignancy; however, its underlying molecular mechanism is unclear. Circular RNAs (circRNAs) serve as significant cancer regulators. The overexpression of circRAPGEF5 in LAD tissues and cells indicated that it may be involved in promoting LAD progression. Analysis of 61 LAD tissues revealed that circRAPGEF5 was related to lymph node metastasis. Functionally, circRAPGEF5 promoted the proliferation, migration, invasion, and epithelial-mesenchymal transition of LAD cells in vitro and promoted LAD cells growth in vivo. Mechanistically, dual-luciferase reporter assays confirmed direct interaction of circRAPGEF5, miR-1236-3p, and ZEB1. miR-1236-3p was upregulated and ZEB1 expression reduced after circRAPGEF5 knockdown, and the proliferation, migration, and invasion of LAD cells was inhibited. circRAPGEF5 was significantly overexpressed in LAD cell exosomes, and co-culture experiments showed that exosomal circRAPGEF5 enhanced the metastatic ability of LAD cells. Further experiments found that serum exosomal circRAPGEF5 was overexpressed in LAD; moreover, the area under the receiver operator characteristic curve of exosomal circRAPGEF5 was superior to that of serum carcinoembryonic antigen (CEA). Jointly detected serum exosomal circRAPGEF5 and serum CEA had better diagnostic performance than when detected individually. Thus, exosomal circRAPGEF5 could promote the proliferation and metastasis of LAD via the miR-1236-3p/ZEB1 axis and serum exosomal circRAPGEF5 may serve as a promising biomarker for LAD.     

Tumor-Suppressive Function of miR-139-5p in Esophageal Squamous Cell Carcinoma

Recent studies have demonstrated the possible function of miR-139-5p in tumorigenesis. However, the exact mechanism of miR-139-5p in cancer remains unclear. In this study, the association of miR-139-5p expression with esophageal squamous cell carcinoma (ESCC) was evaluated in 106 pairs of esophageal cancer and adjacent non-cancerous tissue from ESCC patients. The tumor suppressive features of miR-139-5p were measured by evaluating cell proliferation and cell cycle state, migratory activity and invasion capability, as well as apoptosis. Luciferase reporter assay and Western blot analysis were performed to determine the target gene regulated by miR-139-5p. The mRNA level of NR5A2, the target gene of miR-139-5p, was determined in ESCC patients. Results showed that reduced miR-139-5p level was associated with lymph node metastases of ESCC. MiR-139-5p was investigated to induce cell cycle arrest in the G0/G1 phase and to suppress the invasive capability of esophageal carcinoma cells by targeting the 3′UTR of oncogenic NR5A2. Cyclin E1 and MMP9 were confirmed to participate in cell cycle arrest and invasive suppression induced by NR5A2, respectively. Pearson correlation analysis further confirmed the significantly negative correlation between miR-139-5p and NR5A2 expression. The results suggest that miR-139-5p exerts a growth- and invasiveness-suppressing function in human ESCCs, which demonstrates that miR-139-5p is a potential biomarker for early diagnosis and prognosis and is a therapeutic target for ESCC.     

MiR-139-5p/SLC7A11 inhibits the proliferation,invasion and metastasis of pancreatic carcinoma via PI3K/Akt signaling pathway

ObjectivePancreatic carcinoma (PANC) is one of the important aggressive cancers, with deficiency in effective therapeutics. The study aimed to investigate the effects and molecular mechanism of miR-139-5p/SLC7A11 on the proliferation and metastasis of PANC.MethodsBioinformatics was used to analyze the differentially expressed genes in the TCGA database. PANC cell lines with overexpressed miR-139-5p and Solute Carrier Family 7, Member 11 (SLC7A11) was established, and have been used to detect cell proliferation, invasion and metastasis of PANC Subsequently, bioinformatic analysis and dual luciferase reporter assay were performed to confirm that SLC7A11 was a target gene of miR-139-5p. Xenograft mice model was used to explore the functions of miR-139-5p in PANC tumorigenicity.ResultsMiR-139-5p could regulate and affect the protein expression of P13K and Akt associated with phosphatidylinositol signaling pathway by inhibiting SLC7A11. MiR-139-5p was found to be lowly expressed in PANC tissues, while SLC7A11 was highly expressed. Low expression of miR-139-5p and high expression of SLC7A11 were positively associated with poor clinical outcomes. PANC cell proliferation, invasion and metastasis could be inhibited by miR-139-5p overexpression and be promoted by SLC7A11 overexpression. MiR-139-5p overexpression could suppress PANC tumor growth and the expressions of SLC7A11, p-PI3K, p-Akt in tumor tissues. Therefore, the inhibitory of miR-139-5p to PANC cell proliferation, invasion and metastasis was partly due to its inhibiting effect on SLC7A11 expression.ConclusionOur study proves that miR-139-5p/SLC7A11 has important functions on PANC, suggesting that miR-139-5p can be used as a biomarker for PANC patients.     

Long intergenic noncoding RNA 00641 inhibits breast cancer cell proliferation,migration, and invasion by sponging miR-194-5p

Long noncoding RNAs have an essential role in the tumorigenesis of breast cancer (BC). Nonetheless, the consequences of long intergenic noncoding RNA 00641 (LINC00641) in BC remain unidentified. This study shows that LINC00641 expression level was decreased in BC tissues. LINC00641 expression level was negatively related to tumor size, lymph-node metastasis, as well as clinical stage. LINC00641 overexpression inhibited cell proliferation, migration, and invasion but stimulated apoptosis in BC cells. LINC00641 overexpression also remarkably reduced BC growth and metastasis in vivo. LINC00641 acts as a competitive endogenous RNA to sponge miR-194-5p. miR-194-5p level was higher in BC tissues and cells compared with normal-adjacent tissues and normal breast epithelial cell. miR-194-5p expression was negatively correlated with LINC00641 expression in BC tissues. miR-194-5p overexpression reversed the effects of LINC00641 on cell proliferation, cycle, apoptosis, migration, as well as invasion. In conclusion, LINC00641 inhibits BC cell proliferation, migration, as well as invasion by sponging miR-194-5p.     

MiR-150-5p通过靶向调控Rab1A抑制乳腺癌细胞MDA-231的上皮-间质转化

先前的研究表明,miR-150-5p发挥抑癌基因的作用,调控肿瘤细胞的侵袭与转移。然而,关于其在乳腺癌细胞侵袭与转移中的机制尚不明确。本实验旨在研究miR-150-5p负向调控Rab1A在乳腺癌细胞上皮-间质转化（epithelial-mesenchymal transition,EMT）中的作用。双荧光素酶的结果显示,miR-150-5p可负向调控Rab1A。荧光定量PCR (qRT-PCR) 结果显示,miR-150-5p在乳腺癌细胞MCF-7及MDA-MB-231（MDA-231）中的表达水平明显低于正常乳腺上皮细胞MCF-10A; 在MDA-231中过表达miR-150-5p后,qRT-PCR结果显示,Rab1A mRNA的表达水平明显降低。Western印迹结果显示,过表达miR-150-5p后,miR-150-5p组细胞中的Rab1A、波形蛋白(vimentin)及N-钙黏着蛋白(N-cadherin)的表达水平相对于对照组（NC）细胞明显降低,而E-钙黏着蛋白(E-cadherin)的表达水平明显增加。Transwell侵袭和划痕实验显示,与miR-150-5p+Con组细胞相比,miR-150-5p+Rab1A组细胞的侵袭和迁移能力明显增加。qRT-PCR结果显示,miR-150-5p+Rab1A组细胞的Rab1A mRNA表达水平明显增加。Western印迹结果显示,miR-150-5p+Rab1A组细胞中的波形蛋白、N-钙黏着蛋白表达水平明显增加, 而E-钙黏着蛋白表达明显降低,过表达Rab1A后显著逆转了miR-150-5p对EMT的影响。综上所述,miR-150-5p可以通过负向调控Rab1A抑制EMT,进而抑制乳腺癌细胞的侵袭和迁移。     

miR-377-5p inhibits lung cancer cell proliferation,invasion, and cell cycle progression by targeting AKT1 signaling

Lung carcinoma is the most common type of malignant tumors globally, and its molecular mechanisms remained unclear. With the aim to investigate the effects of microRNA (miR)-377-5p on the cell development, invasion, metastasis, and cycle of lung carcinoma, this study was performed. We evaluated miR-377-5p expression levels in lung cancer tissues and cell models. Cell viability, proliferation, migration, invasion abilities, and cell cycle distribution were measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, crystal violet, transwell, and flow cytometry assay. Furthermore, expression levels of protein kinase B α subunit (AKT1) and proteins related to cell cycle and epithelial-mesenchymal transition (EMT) were assessed using Western blot analysis and quantitative real-time polymerase chain reaction. These results suggested that miR-377-5p was downregulated in vivo and in cell models, and miR-377-5p overexpression inhibited cell viability, proliferation, migration, invasion, and induced cell-cycle arrest. In addition, as a target of miR-377-5p, AKT1 alleviated the decreases of cell viability, proliferation, migration, invasion, the S-phase cells, the expression of cyclin D1, fibronectin, and vimentin, as well as the increases of the G0/G1-phase cells, the expression of Foxo1, p27 ^kip1, p21 ^Cip1 and E-cadherin when miR-377-5p overexpressed. In conclusion, miR-377-5p inhibited cell development and regulated cell cycle distribution and EMT by targeting AKT1, which provided a theoretical basis for further study of lung carcinoma therapeutics.     

基于生物信息学分析研究miR-182-5p通过靶向调控EP300促进乳腺癌细胞的侵袭和转移

近期研究表明,miR-182-5p对多种癌症的侵袭和转移具有重要作用,但其在乳腺癌侵袭转移中的研究相对较少。本研究通过网上在线microRNA分析工具下载乳腺癌组织及正常乳腺组织表达比较的数据集,分析发现在GSE4589、GSE38167、GSE61438等3个数据库中,在乳腺癌组织中存在26个相同的microRNA,其中8个上调,而我们实验验证发现hsa-miR-182在8例病理组织中的表达上调差异最显著(P=0.001),选定目的基因hsa-miR-182;qRT-PCR检测细胞中miR-182-5p的表达,结果显示,与MCF-10A相比,miR-182-5p在MDA-MB-231、T47D、MDA-MB-453、MCF-7中表达上调(P<0.05);转染miR-182-5p干扰质粒,qRT-PCR检测细胞中miR-182-5p的表达情况。结果显示,miR-182-5p表达显著降低(P=0.003),提示转染成功;Transwell侵袭结果显示,MDAMB-231细胞敲低miR-182-5p,与对照组相比,体外侵袭能力明显降低(P=0.002);Western印迹检测转染miR-182-5p干扰质粒时,MDA-MB-231中上皮-间质转化(epithelial-mesenchymal transition,EMT)相关标志物的表达情况,结果显示,与对照组相比,敲低miR-182-5p使细胞中上皮-钙黏着蛋白(E-cadherin)表达上调,神经-钙黏着蛋白(N-cadherin)、波形蛋白(vimentin)表达下调。为研究探讨miR-182-5p的靶蛋白,采用在线预测软件预测可能与miR-182-5p结合的靶蛋白,cytoscape构建蛋白质互作网络图并筛选出hub基因;双荧光素酶结果证实,miR-182-5p可与EP300靶向结合(P=0.001);采用qRT-PCR、Western印迹检测转染miR-182-5p干扰质粒后EP300在mRNA及蛋白质水平的表达,结果显示,与对照组相比,在敲低miR-182-5p组中EP300在mRNA及蛋白质的表达上调(P=0.001)。综上所述,miR-182-5p可靶向调节EP300,促进乳腺癌细胞的侵袭与转移。     

MicroRNA-150 Predicts a Favorable Prognosis in Patients with Epithelial Ovarian Cancer,and Inhibits Cell Invasion and Metastasis by Suppressing Transcriptional Repressor ZEB1

MicroRNA (miR)-150 has been reported to be dramatically downregulated in human epithelial ovarian cancer (EOC) tissues and patients’ serum compared to normal controls. This study aimed to investigate clinical significance and molecular mechanisms of miR-150 in EOC. In the current study, quantitative real-time PCR analysis showed that miR-150 was significantly downregulated in human EOC tissues compared to normal tissue samples. Then, we demonstrated the significant associations of miR-150 downregulation with aggressive clinicopathological features of EOC patients, including high clinical stage and pathological grade, and shorter overall and progression-free survivals. More importantly, the multivariate analysis identified miR-150 expression as an independent prognostic biomarker in EOC. After that, luciferase reporter assays demonstrated that Zinc Finger E-Box Binding Homeobox 1 (ZEB1), a crucial regulator of epithelial-to-mesenchymal transition (EMT), was a direct target of miR-150 in EOC cells. Moreover, we found that the ectopic expression of miR-150 could efficiently inhibit cell proliferation, invasion and metastasis by suppressing the expression of ZEB1. Furthermore, we also observed a significantly negative correlation between miR-150 and ZEB1 mRNA expression in EOC tissues (rs = –0.45, P<0.001). In conclusion, these findings offer the convincing evidence that aberrant expression of miR-150 may play a role in tumor progression and prognosis in patients with EOC. Moreover, our data reveal that miR-150 may function as a tumor suppressor and modulate EOC cell proliferation, and invasion by directly and negatively regulating ZEB1, implying the re-expression of miR-150 might be a potential therapeutic strategy for EOC.     

Long non‐coding RNA ZEB2‐AS1 promotes the proliferation,metastasis and epithelial mesenchymal transition in triple‐negative breast cancer by epigenetically activating ZEB2

The triple‐negative breast cancer is the most malignant type of breast cancer. Its pathogenesis and prognosis remain poor despite the significant advances in breast cancer diagnosis and therapy. Meanwhile, long noncoding RNAs (LncRNAs) play a pivotal role in the progression of malignant tumors. In this study, we found that LncRNA‐ZEB2‐AS1 was dramatically up‐regulated in our breast cancer specimens and cells (MDA231), especially in metastatic tumor specimens and highly invasive cells, and high lncRNA‐ZEB2‐AS1 expression is associated with clinicopathologic features and short survival of breast cancer patients. LncRNA‐ZEB2‐AS1 promotes the proliferation and metastasis of MDA231 cells in SCID mice. Thus, it is regarded as an oncogene in triple‐negative breast cancer. It is mainly endo‐nuclear and situated near ZEB2, positively regulating ZEB2 expression and activating the epithelial mesenchymal transition via the PI3K/Akt/GSK3β/Zeb2 signaling pathway. Meanwhile, EGF‐induced F‐actin polymerization in MDA231 cells can be suppressed by reducing lncRNA‐ZEB2‐AS1 expression. The migration and invasion of triple‐negative breast cancer can be altered through cytoskeleton rearrangement. In summary, we demonstrated that lncRNA‐ZEB2‐AS1 is an important factor affecting the development of triple‐negative breast cancer and thus a potential oncogene target.