scholarly journals miR-494 Sensitizes Gastric Cancer Cells to TRAIL Treatment Through Downregulation of Survivin

2018 ◽  
Vol 51 (5) ◽  
pp. 2212-2223 ◽  
Author(s):  
Shuning Xu ◽  
Danyang Li ◽  
Tianyuan Li ◽  
Lei Qiao ◽  
Ke Li ◽  
...  

Background/Aims: TNF-related apoptosis-inducing ligand (TRAIL) is a novel and low-toxic anti-tumor drug used for various cancers. However, cancer cells usually develop mechanisms to acquire the resistance against TRAIL. Among these changes, dysregulation of microRNAs (miRNAs) usually occurs in cancer cells and is responsible for induction of drug resistance. Methods: Expression of miR-494 in gastric cancer tissues and cell lines was detected by quantitative reverse transcriptase real time PCR (qRT-PCR) analysis. Effect of miR-494 on regulating the TRAIL sensitivity to gastric cancer cell lines was evaluated by MTT assays. Bioinformatics and luciferase reporter assays were used to confirm the regulation of miR-494 on survivin. Mitochondrial apoptosis pathway in gastric cancer cells was tested by western blot and flow cytometry analysis. Results: Obvious downregulation of miR-494 was observed in gastric cancer cells. Furthermore, we found that expression profile of miR-494 was associated with TRAIL-sensitivity in gastric cancer. Enforced expression of miR-494 was found to sensitize the gastric cancer cells to TRAIL-induced cytotoxicity. Mechanically, Luciferase reporter assays proved that survivin was the target of miR-494 in gastric cancer cells. Enforced expression of miR-494 decreased the expression of survivin, and thus promoted the TRAIL-induced mitochondria collapse and apoptosis pathway. Conclusion: MiR-494/survivin axis represents a potential mechanism which is responsible for TRAIL resistance in gastric cancer cells. Increasing the miR-494 expression may serve as a novel therapeutic strategy to sensitize gastric cancer cells to TRAIL treatment.

2020 ◽  
Author(s):  
Yi Gao ◽  
Yanfeng Wang ◽  
Xiaofei Wang ◽  
Changan Zhao ◽  
Fenghui Wang ◽  
...  

Abstract Background: In recent years, many microRNAs(miRNAs) involved in cancer progression. The aberrant expression of miR-335-5p in tumorigenesis has been demonstrated. The present study aimed to investigate the molecular mechanisms underlying miR-335-5p- regulated MAPK10 expression in human gastric cancer(GC).Methods: The quantitative real-time PCR was used to study the level of miR-335-5p expression in gastric cancer cell lines and tissues. Subsequently, the MTT and cloning formation assays were used to detect cell proliferation, while transwell and wound-healing assays were used to identify invasion and migration of the gastric cancer cells. The correlation between the miR-335-5p and the cell cycle-related target gene mitogen‑activated protein kinase 10 (MAPK10) in gastric cancer was analyzed based on the website. In addition, the target gene of miR-335-5p was detected by luciferase reporter assay, qRT-PCR, and western blotting.Results: The miR-335-5p level was down-regulated in GC tissues and cell lines. Furthermore, miR-335-5p inhibited proliferation, migration of gastric cancer cells, and induced apoptosis. During the G1/S phase, miR-335-5p arrested the cycle of gastric cancer cells in vitro. The correlation between the miR-335-5p and the cell cycle-related target gene MAPK10 in GC was analyzed, MAPK10 was directly targeted by the miR-335-5p.Conclusion: These data suggested that miR-335-5p acts as a tumor suppressor, and go through the MAPK10 to inhibit the GC progression.


Author(s):  
Chunsheng Li ◽  
Jingrong Dong ◽  
Zhenqi Han ◽  
Kai Zhang

MicroRNAs (miRNAs) are reportedly involved in gastric cancer development and progression. In particular, miR-219-5p has been reported to be a tumor-associated miRNA in human cancer. However, the role of miR-219-5p in gastric cancer remains unclear. In this study, we investigated for the first time the potential role and underlying mechanism of miR-219-5p in the proliferation, migration, and invasion of human gastric cancer cells. miR-219-5p was found to be markedly decreased in gastric cancer tissues and cell lines compared with adjacent tissues and normal gastric epithelial cells. miR-219-5p mimics or anti-miR-219-5p was transfected into gastric cancer cell lines to overexpress or suppress miR-219-5p expression, respectively. Results showed that miR-219-5p overexpression significantly decreased the proliferation, migration, and invasion of gastric cancer cells. Conversely, miR-219-5p suppression demonstrated a completely opposite effect. Bioinformatics and luciferase reporter assays indicated that miR-219-5p targeted the 3′-untranslated region of the liver receptor homolog-1 (LRH-1), a well-characterized oncogene. Furthermore, miR-219-5p inhibited the mRNA and protein levels of LRH-1. LRH-1 mRNA expression was inversely correlated with miR-219-5p expression in gastric cancer tissues. miR-219-5p overexpression significantly decreased the Wnt/β-catenin signaling pathway in gastric cancer cells. Additionally, LRH-1 restoration can markedly reverse miR-219-5p-mediated tumor suppressive effects. Our study suggests that miR-219-5p regulated the proliferation, migration, and invasion of human gastric cancer cells by suppressing LRH-1. miR-219-5p may be a potential target for gastric cancer therapy.


2018 ◽  
Vol 49 (6) ◽  
pp. 2151-2162 ◽  
Author(s):  
Bo Lian ◽  
Dongxiang Yang ◽  
Yanlong Liu ◽  
Gang Shi ◽  
Jibin Li ◽  
...  

Background/Aims: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is an ideal anti-tumor drug because it exhibits selective cytotoxicity against cancer cells. However, certain cancer cells are resistant to TRAIL, and the potential mechanisms are still unclear. The aim of this study was to reduce the resistance of colorectal cancer (CRC) cells to TRAIL. Methods: Quantitative real-time PCR analysis was performed to detect the expression of microRNA-128 (miR-128) in tissues from patients with CRC and CRC cell lines. MTT assays were used to evaluate the effect of miR-128 on TRAIL-induced cytotoxicity against CRC cell lines. The distribution of death receptor 5 (DR5) and the production of reactive oxygen species (ROS) were detected by flow cytometry analysis. Western blot, flow cytometry, and luciferase reporter assays were performed to evaluate the potential mechanism and pathway of miR-128-promoted apoptosis in TRAIL-treated CRC cells. Results: MiR-128 expression was downregulated in tumor tissues from patients with CRC as well as in CRC cell lines in vitro. The enforced expression of miR-128 sensitized CRC cells to TRAIL-induced cytotoxicity by inducing apoptosis. Mechanistically, bioinformatics, western blot analysis, and luciferase reporter assays showed that miR-128 directly targeted sirtuin 1 (SIRT1) in CRC cells. miR-128 overexpression suppressed SIRT1 expression, which promoted the production of ROS in TRAIL-treated CRC cells. This increase of ROS subsequently induced DR5 expression, and thus increased TRAIL-induced apoptosis in CRC cells. Conclusion: The combination of miR-128 with TRAIL may represent a novel approach for the treatment of CRC.


2019 ◽  
Vol 37 (15_suppl) ◽  
pp. e14719-e14719
Author(s):  
Hyeong Su Kim ◽  
Dae Young Zang ◽  
Sung-Hwa Sohn ◽  
Bohyun Kim ◽  
Hee Jung Sul

e14719 Background: VEGFA is the key mediator of angiogenesis in cancer and previous studies reported that VEGFA expression was significantly up-regulated in gastric cancer tissues compared with matched normal tissues. We showed that increased levels of VEGFA are significantly associated with expression of hepatocyte growth factor receptor (MET) (r = 0.6255, P < 0.0001). In addition, it is well known that c-MET is potentially a highly plausible target for cancer therapy in gastric cancer. In this study, cytotoxic activity of tivantinib were evaluated in gastric cancer cells with high c-MET expression or VEGFA amplification. Methods: In this study, Western blot and quantitative real-time PCR analysis were used to detect the expression of protein and genes after treatment of tivantinib. In addition, MTS, flow cytometry, and migration assay were used. Results: Tivantinib inhibited growths of a high c-MET-expressed or VEGFA-amplified cell lines. Furthermore, in migration and apoptosis analysis, tivantinib induced apoptosis of SNU620, MKN45 (carried VEGFB mutation), AGS, and MKN28 cells but not in KATO III (carried VEGFB and VEGFC mutation) cells. We also found that tivantinib inhibited the VEGF signaling pathway and MYC expression in VEGFA-amplified gastric cancer cell lines. Conclusions: The data indicate that tivantinib could be a potential therapeutic agent for the treatment of gastric cancer with high c-MET expression or VEGFA amplification.


2017 ◽  
Vol 8 (4) ◽  
pp. 636-645 ◽  
Author(s):  
Peizhun Du ◽  
Jing Zhao ◽  
Jing Wang ◽  
Yongchao Liu ◽  
Hong Ren ◽  
...  

2016 ◽  
Vol 39 (2) ◽  
pp. 453-466 ◽  
Author(s):  
Qi Zhou ◽  
Xiao Zheng ◽  
Lujun Chen ◽  
Bin Xu ◽  
Xin Yang ◽  
...  

Background/Aims: Transforming growth factor beta (TGF-β) plays a major role in tumorigenesis. MicroRNA-181b (miRNA-181b) is a multifaceted miRNA that has been implicated in many cellular processes such as cell fate determination and cellular invasion. This study aimed to confirm the relationship of miRNA-181b and the TGF-β-Smad2/3/4 pathway with the induction of the epithelial-to-mesenchymal transition (EMT) in gastric cancer. Methods: This study investigated the ability of TGF-β to induce migration by wound healing and transwell invasion assays in human gastric cancer cell lines. miRNA expression was altered using miRNA-181b mimic and inhibitor in the same system. Expression of miRNA-181b, the hypothetical target gene Timp3 and EMT-related markers were analyzed by real-time real-time quantitative RT-PCR. Immunoblotting was used to investigate the levels of phospho-Smad2 and Smad4. Dual-luciferase reporter assays were performed to confirm the direct binding of miRNA-181b to Timp3. Results: miRNA-181b was significantly upregulated in response to TGF-β treatment in gastric cancer cell lines. Overexpression of miR-181b mimic induced an in vitro EMT-like change to a phenotype similar to that following TGF-β treatment alone and was reversed by miRNA-181b inhibitor. Inhibition of TGF-β−Smad2/3 signaling with SD-208 significantly attenuated the upregulation of miRNA-181b. Knockdown of Smad4 in gastric cancer cells strongly attenuated the upregulation of miRNA-181b. Moreover, miR-181b was found to directly target the 3′ untranslated region (3′UTR) of Timp3 mRNA affecting TGF-β-induced EMT. Conclusions: Our results elucidate a novel mechanism through which the TGF-β pathway regulates the EMT of gastric cancer cells by increasing the levels of miRNA-181b to target Timp3 via the Smad2/3/4-dependent pathway. These findings provide insights into the cellular and environmental factors regulating EMT, which may guide future studies on therapeutic strategies targeting these cells.


2017 ◽  
Vol 42 (3) ◽  
pp. 999-1012 ◽  
Author(s):  
Kai Yan ◽  
Jie Tian ◽  
Wenzheng Shi ◽  
Hao Xia ◽  
Yuanfang Zhu

Background/Amis: Long non-coding RNAs (lncRNAs), a novel class of transcripts, have been shown to play critical roles in diverse cellular biological processes, including tumorigenesis. Small nucleolar RNA host gene 6 (SNHG6) regulates various biological processes in cancer cells. However, the biological role of SNHG6 in gastric cancer still remains to be explored. The aim of this study is to investigate the characteristic of the SNHG6 in gastric cancer. Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure the expression of SNHG6 in gastric cancer tissues and cell lines. MTT assays, colony formation assays were used to determine the impact of SNHG6 on tumorigenesis . Flow cytometric analysis of cell cycle and apoptosis was performed to measure the effect of SNHG6 on cell cycle and apoptosis rate. Transwell assay was performed to measure the effect of SNHG6 on cell migration. Western blotting and immunofuorescence were utilized to examine the effect of SNHG6 on epithelial-mesenchymal transition (EMT) of GC cells. Chromatin immunoprecipitation (ChIP), RNA immunoprecipitation (RIP), RNA-pulldown and luciferase reporter assays were employed to dissect molecular mechanisms. Results: In this study, we revealed that SNHG6 was overexpressed in gastric cancer tissues and cell lines. High expression levels of SNHG6 wereassociated with invasion depth, lymph node metastasis, distant metastasis and tumor/node/metastasis (TNM) stage, and predicted poor prognosis. Loss-of-function assays revealed that silenced SNHG6 obviously inhibited gastric cancer cell growth, weakened cell migration capacity and suppressed the EMT processes of gastric cancer cells. Additionally, ChIP, RIP, RNA-pulldown and luciferase reporter assays evidenced that SNHG6 could epigenetically silenced p27 and could competitively sponging miR-101-3p thereby regulating zinc finger E-box-binding homeobox 1 (ZEB1). Conclusion: In summary, our findings demonstrated that SNHG6 acted as an oncogene in gastric cancer cells through regulating miR-101-3p/ZEB1 at a post-transcriptional level and silencing expression at a transcriptional level by recruiting enhancer of zeste homolog 2 (EZH2) to the promoter of p27. SNHG6 might serve as a candidate prognostic biomarker and a target for novel therapies of gastric cancer patients.


2021 ◽  
Author(s):  
Chuanliang Liu ◽  
Dan Wang ◽  
Lei Li ◽  
Ruihua Zhang

Abstract Background: Ferroptosis is a newly described form of regulated cell death, targeting nuclear factor erythroid-2-related factor 2 (Nrf2) -mediated ferroptosis may be an attractive option to counteract malignant tumor. Whether miR-144-5p sensitize erastin-induced ferroptosis in gastric cancer via regulation of Nrf2 pathway is unclear. Methods: To speculate the function of miR-144-5p in cancers, bioinformatic analysis was performed. Dual-luciferase reporter gene assay was used to predict effect of miR-144-5p on the expression of Nrf2. The expressions of miR-144-5p and Nrf2 in human gastric cancer cell lines and tissues were detected by qPCR, Immunohistochemistry or western blot. Results: miR-144-5p, identified to wreck Nrf2 mRNA, was selected and overexpressed in gastric cancer cells to sensitize erastin-induced ferroptosis. Ectopic expression of miR-144-5p in AGS and BGC-823 cells downregulated the mRNA and protein expression of Nrf2. In addition, AGS and BGC-823 cell lines with exogenous expression of miR-144-5p were more sensitive to erastin-induced ferroptosis with overgeneration of lipid reactive oxygen species and depletion of glutathione. Conclusions: miR-144-5p sensitizes erastin-induced ferroptosis via abrogating expression of Nrf2 to eliminate cancer cells selectively with high Nrf2 pathway activation.


Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1820
Author(s):  
Chengcheng Hao ◽  
Yuxin Cui ◽  
Jane Lane ◽  
Shuqin Jia ◽  
Jiafu Ji ◽  
...  

Background: Osteopontin (OPN) splice variants are identified as predictors of tumour progression and therapeutic resistance in certain types of solid tumours. However, their roles in gastric cancer (GC) remain poorly characterized. The current study sought to assess the prognostic value of the three OPN splice variants (namely OPN-a, OPN-b, and OPN-c) in gastric cancer and their potential functions within gastric cancer cells. Methods: RNA extraction and reverse transcription were performed using our clinical cohort of gastric carcinomas and matched normal tissues (n = 324 matched pairs). Transcript levels were determined using real-time quantitative PCR. Three OPN splice variants overexpressed cell lines were created from the gastric cancer cell line HGC-27. Subsequently, biological functions, including cell growth, adhesion, migration, and invasion, were studied. The potential effects of OPN isoforms on cisplatin and 5-Fu were evaluated by detecting cellular reactive oxygen species (ROS) levels in the HGC-27-derived cell lines. Results: Compared with normal tissues, the expression levels of three splice variants were all elevated in gastric cancer tissues in an order of OPN-a > OPN-b > OPN-c. The OPN-a level significantly increased with increasing TNM staging and worse clinical outcome. There appeared to be a downregulation for OPN-c in increasing lymph node status (p < 0.05), increasing TNM staging, and poor differentiation. High levels of OPN-a and OPN-b were correlated with short overall survival and disease-free survival of gastric cancer patients. However, the low expression of OPN-c was significantly associated with a poor prognosis. Functional analyses further showed that ectopic expression of OPN-c suppressed in vitro proliferation, adhesiveness, migration, and invasion properties of HGC-27 cells, while the opposite role was seen for OPN-a. Cellular ROS detection indicated that OPN-a and OPN-c significantly promoted ROS production after treatment with 5-Fu comparing to OPN-vector, while only OPN-a markedly induced ROS production after treatment with cisplatin. Conclusion: Our results suggest that OPN splice variants have distinguished potential to predict the prognosis of gastric cancer. Three OPN variants exert distinctive functions in gastric cancer cells. Focusing on specific OPN isoforms could be a novel direction for developing diagnostic and therapeutic approaches in gastric cancer.


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