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Objective@#To investigate the expression of microRNA-133b (miR-133b) in esophageal squamous cell carcinoma (ESCC), and explore its effect and the underlying molecular mechanisms on cell proliferation and invasion.@*Methods@#Real-time quantitative PCR (qPCR) was used to examine miR-133b expression in 63 ESCC tissues and paired adjacent non-cancerous tissues, several ESCC cells (Eca109, EC9706, EC1, TE1, KYSE70) and normal esophageal epithelial cell Het-1A. MiR-133b mimic, inhibitor and negative control (NC) were transfected into TE1 cells. The effect of miR-133b on cell proliferation and invasion were determined by CCK-8 and Transwell assays, respectively. Subsequently, the target gene of miR-133b was predicted by online tools TargetScan and miRDB, which was verified by dual luciferase reporter assays. Finally, Western blot was utilized to detect the effects of miR-133b overexpression on expression of target gene TAGLN2 as well as EMT-related proteins E-cadherin, N-cadherin, Snail, Slug and Vimentin.@*Results@#Relative levels of miR-133b in ESCC tissues (0.295±0.040) were significantly lower than those in adjacent non-cancerous tissues (1.002±0.011, P<0.001). The expression of miR-133b was tightly associated with clinical staging, lymph node metastasis and prognosis. Moreover, relative levels of miR-133b in ESCC cells Eca109, EC9706, EC1, TE1 and KYSE70 (0.679±0.031, 0.391±0.008, 0.236±0.016, 0.031±0.005 and 0.099±0.020) were evidently lower than that in normal esophageal epithelial cell Het-1A (1.005±0.016, all P<0.001). In TE1 cells, miR-133b mimic significantly increased the level of miR-133b to 6.199±0.627, and suppressed cell proliferation and invasion, whereas miR-133b inhibitor obviously decreased its expression to 0.182±0.023, and promoted cell proliferation and invasion. Most notably, the relative luciferase activities of miR-133b-mimic group (0.320±0.018) in TE1 cells transfected with TAGLN-3′UTR-WT were markedly lower than that in NC group (1.010±0.036, P<0.001), whereas those in TAGLN-3′UTR-MUT transfection cells were 1.019±0.056 and 1.008±0.021, respectively, showing no significantly statistical difference (P>0.05). Furthermore, miR-133b overexpression markedly downregulated TAGLN2, N-cadherin, Snail, Slug and Vimentin levels, and increased E-cadherin expression.@*Conclusion@#MiR-133b plays an important role in the proliferation and invasion of ESCC cells by regulating TAGLN2 expression, and it may be a potential therapeutic target for ESCC patients.
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Objective To investigate the effect of netropsin on migration and invasion ability of gastric cancer cells and its mechanisms.Methods To determine if netropsin inhibits migration and invasion of gastric cancer cells, Transwell migration and invasion assay was performed.Then Western blot was performed to detect expression of E-cadherin and vimentin in gastric cancer cells with or without presence in medium netropsin.Finally, immunofluorescence was performed to detect changes in the cellular localization of β-catenin to validate whether Wnt/β-catenin pathway was suppressed or not.Results Netropsin with the concentration of 25 μmol/L had minimal inhibition effect on cell proliferation and was able to suppress ability of migration and invasion by inhibiting EMT in gastric cancer cells(P<0.05).Meanwhile netropsin was able to down-regulate the expression of epithelial markers E-cadherin and up-regulate the expression of mesenchymal marker vimentin.Finally,immunofluorescence showed that netropsin was able to block translocation of β-catenin from cytoplasm to nuclear.Conclusions Netropsin can inhibit EMT thereby suppressing migration and invasion of gastric cancer cells.The mechanism is that netropsin can compete with HMGA2 for transcription factor binding site thereby suppressing the Wnt/β-catenin pathway.
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Objective:To investigate whether the overexpression of Oct4B1 gene induces epithelial mesenchymal transition in human colorectal cancer SW480 cells and its possible mechanism.Methods: Experimental group(SW480-Oct4B1):Transfection of SW480 cell lines in colorectal cancer with Oct4B1 overexpression plasmid;Control group(SW480-Oct4B1):negative control plasmid with G418 resistance.Stably transfected cell lines were obtained by G418 culture medium.The two groups were compared with:①Detection of Oct4B1 gene expression in stably transfected cell lines by RT-qPCR;②Scratches and Transwell assays were used to estimate migration and invasion;③Detection of EMT related markers E-cadherin,N-cadherin and Vimentin protein expression by Western blot assay;④Detection of Twist gene and protein expression by RT-PCR and Western blot assays.Results: The transient transfection was confirmed by RT-qPCR and the stable transfected cell lines were obtained from two groups of cells transfected with G418 culture medium.Compared with the control group:①RT-qPCR revealed increased expression of Oct4B1 gene in the experimental group(P<0.01);②Cell migration and invasion were significantly increased(P<0.01);③Epithelial marker:the expression of E-cadherin protein was significantly decreased (P<0.01),interstitial marker:the expression of N-cadherin and Vimentin protein was significantly increased (P<0.01);④Twist mRNA and protein expression were significantly increased(P<0.01).Conclusion: Overexpression of Oct4B1 gene can induce epithelial mesenchymal transition in human colorectal cancer SW480 cells,its molecular mechanism may be related to the promotion of Twist expression.
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Hepatocellular carcinoma (HCC) is a common malignancy, of which the 5-year survival rate is 39% merely. HCC current treatments include surgery, interventional chemotherapy, radiofrequency ablation, and targeting drug delivery. As a typical hyper-vascular cancer, HCC can be inhibited via tumor angiogenesis inhibitors (TAI). However, TAI can not completely block the nutrient supply of the tumor tissue during treatment, since there exists a special way of blood supply named vascular mimicry (VM) in HCC. Through these pipes similar to the blood vessels HCC can communicate with the host blood vessels and thus acquire blood supply for the growth, invasion and metastasis. A growing number of studies have found that the presence of angiogenesis mimicry structure is one of the key factors limiting TAI in the treatment of liver cancer. This article gave an outline of VM and summarized the formation mechanism of VM and the research status about the hepatocarcinoma therapy.
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Epithelial-mesenchymal transition (EMT) not only can endow cells migration and invasion characteristics,but also can make tumor cells obtain self-renewal ability and have the characteristics of stem cells,which might result in cancer stem cell (CSCs).There are the same molecular mechanism and microenvironment between EMT and CSCs,which have great clinic significances for the diagnosis and treatment of the aggressive cancers.Moreover,many studies show that miR-200 could regulate EMT and CSC,participate in the tumor invasion and metastasi,and promote the research of targeted cancer therapy.
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Epithelial-mesenchymal transition (EMT) is the basis of biological process of embryonic development,and is also closely related with tumor cell in situ invasion and distant metastasis.Recent studies find that EMT and cancer stem cells (CSCs) have a close relationship.CSCs have a strong ability to selfrenewal,tumorigenicity and cell differentiation potential.Identifing the markers,in-depth study of CSCs resistance,may provide a new path for cancer treatment.
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The epithelial-mesenchymal transition (EMT) is characterized by absence of epithelial phenotype and acquiring of mesenchymal properties. EMT participates not only in normal embryonic development, wound healing and tissue reconstruction, but also in various pathologic processes, including fibrosis and carcinogenesis. EMT can facilitate the invasion and metastasis of cancer cells to distant tissues, and confer the metastatic cancer cells self-renewal ability of stem cells, contributing to macroscopical metastasis formation and multiple resistance to treatment. Recent studies have revealed that several transcription factors, signaling pathways, microRNAs and microenvironment components are involved in this process. Here we summarize the recent progress on the roles of EMT and cancer stem cells in tumor metastasis, hoping to provide new insights in target therapy of tumor metastasis and recurrence.
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Tumor metastasis, the main characteristic and important indication of malignant tumor, is also the primary cause of death for most cancer patients. The tumor metastasis is a multistep process involving various factors, multiple interactions of many genes as well as the microenvironment. To investigate the mechanism of tumor metastasis will help us understand the essences of metastasis process, therefore exploring molecular targets for clinical diagnosis and treatment of cancer.
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Tumor metastasis, the main characteristic of malignance tumor, is the primary cause of death for most cancer patients.The initiation of tumor metastasis involves complex signaling pathway within tumor cell and microenvironment, mediating primary tumor metastasis, invasion, survival and arrest in the blood circulation, and progressive growth at the distant site.The most research on the mechanism of tumor metastais will help understand the metastasis process, and identify promising molecular targets for cancer clinical diagnosis and treatment.