scholarly journals circ-SIRT1 Promotes Colorectal Cancer Proliferation and EMT by Recruiting and Binding to eIF4A3

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Xiangjie Wang ◽  
Shuang Liu ◽  
Bin Xu ◽  
Yabin Liu ◽  
Peng Kong ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Noncoding Rna ◽  
Circular Rna ◽  
Cell Counting ◽  
Cancer Proliferation ◽  
Rna Immunoprecipitation ◽  
Invasive Capacity ◽  
Underlying Mechanisms ◽  
Sirt1 Gene ◽  
Related Proteins

Circular RNA (circRNA), a recently identified type of endogenous noncoding RNA, has been implicated in the occurrence and development of a variety of tumors; however, whether circ-SIRT1, derived from pre-mRNA of the parental SIRT1 gene, is involved in colorectal cancer (CRC) remains unknown, as do the potential underlying mechanisms. The expression of circ-SIRT1 in CRC cells and tissue was detected by RT-qPCR. Colony formation and Cell Counting Kit-8 assays were used to evaluate the effect of circ-SIRT1 knockdown on the proliferative ability of CRC cells. Wound healing and Transwell assays were used to assess the effect of circ-SIRT1 knockdown on the migratory and invasive capacity of CRC cells. RNA immunoprecipitation and RNA pull-down assays were employed to validate the binding of circ-SIRT1 to EIF4A3. Western blot was used to identify the changes in the expression of EIF4A3 and EMT-related proteins. The RT-qPCR results showed that circ-SIRT1 was highly expressed in CRC cells and tissue and was positively correlated with the depth of tumor invasion. Knocking down circ-SIRT1 inhibited the proliferation and invasion of CRC cells and EMT. We further found that EIF4A3 could bind to circ-SIRT1, and that overexpressing circ-SIRT1 decreased the abundance of EIF4A3 at the mRNAs of the EMT marker proteins N-cadherin and vimentin. Combined, our findings suggested that circ-SIRT1 regulates the expression of EMT-related proteins by preventing EIF4A3 recruitment to the respective mRNAs. Our results further indicate that circ-SIRT1 functions as an oncogene in CRC by promoting the proliferation, invasion, and EMT of CRC cells through the circ-SIRT1/EIF4A3/N-cadherin/vimentin pathway.

scholarly journals Exosome-Mediated Transfer of circ_0000338 Enhances 5-Fluorouracil Resistance in Colorectal Cancer through Regulating MicroRNA 217 (miR-217) and miR-485-3p

2021 ◽  
Vol 41 (5) ◽  
Author(s):  
Kui Zhao ◽  
Xiaohui Cheng ◽  
Zhenyu Ye ◽  
Yecheng Li ◽  
Wei Peng ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Circular Rna ◽  
Cell Counting ◽  
Luciferase Reporter ◽  
Diagnostic Efficiency ◽  
Transmission Electron ◽  
Proliferation And Apoptosis ◽  
Rna Immunoprecipitation

ABSTRACT Exosomes are microvesicles secreted by body cells for intercellular communication. The circular RNA circ_0000338 was found to be present in extracellular vesicles and improve the chemoresistance of colorectal cancer (CRC) cells. However, the role of exosomal circ_0000338 in 5-fluorouracil (5-FU) resistance in CRC is largely unknown. The levels of circ_0000338, microRNA 217 (miR-217), and miR-485-3p were detected using quantitative real-time PCR (qRT-PCR). The 50% inhibitory concentration (IC50) values of cells for 5-FU, cell proliferation, and apoptosis were evaluated using cell counting kit 8 (CCK-8), colony formation, flow cytometry, and Western blot assays. The interaction between miR-217 or miR-485-3p and circ_0000338 was confirmed by RNA immunoprecipitation (RIP), dual-luciferase reporter, and pulldown assays. Exosomes were isolated by ultracentrifugation and qualified by transmission electron microscopy (TEM), Nanosight tracking analysis (NTA), and Western blotting. Xenograft models were performed to analyze whether circ_0000338-loaded exosomes could increase resistance of CRC cells to 5-FU in vivo. The circ_0000338 level was elevated in 5-FU-resistant CRC tissues and cells, and circ_0000338 knockdown sensitized 5-FU-resistant CRC cells to 5-FU through enhancing apoptosis and decreasing proliferation in vitro. Mechanistically, circ_0000338 directly bound to miR-217 and miR-485-3p, and the inhibition of miR-217 or miR-485-3p reversed the effects of circ_0000338 knockdown on cell 5-FU resistance in CRC. Additionally, extracellular circ_0000338 could be incorporated into secreted exosomes and transmitted to 5-FU-sensitive cells. Treatment-sensitive cells with exosomes containing circ_0000338 reduced the 5-FU response in CRC both in vitro and in vivo. Besides that, the exosomal circ_0000338 concentration was higher in patients exhibiting resistance to 5-FU and showed good diagnostic efficiency in 5-FU-resistant CRC. The delivery of circ_0000338 via exosomes enhanced 5-FU resistance in CRC through negative regulation of miR-217 and miR-485-3p, indicating a promising diagnostic and therapeutic marker for 5-FU-based chemotherapy in CRC patients.

scholarly journals Circular RNA circCSPP1 knockdown attenuates doxorubicin resistance and suppresses tumor progression of colorectal cancer via miR-944/FZD7 axis

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lanlan Xi ◽  
Quanlin Liu ◽  
Wei Zhang ◽  
Linshan Luo ◽  
Jingfeng Song ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Tumor Growth ◽  
Circular Rna ◽  
Luciferase Reporter ◽  
Circular Rnas ◽  
Protein Levels ◽  
Cell Progression ◽  
Rna Immunoprecipitation ◽  
Induced Apoptosis

Abstract Background Circular RNAs (circRNAs) have been reported to play vital roles in colorectal cancer (CRC). However, only a few circRNAs have been experimentally validated and functionally described. In this research, we aimed to reveal the functional mechanism of circCSPP1 in CRC. Methods 36 DOX sensitive and 36 resistant CRC cases participated in this study. The expression of circCSPP1, miR-944 and FZD7 were detected by quantitative real time polymerase chain reaction (qRT-PCR) and the protein levels of FZD7, MRP1, P-gp and LRP were detected by western blot. Cell proliferation, migration, invasion, and apoptosis were assessed by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay, transwell assay, or flow cytometry analysis, respectively. The interaction between miR-944 and circCSPP1 or frizzled-7 (FZD7) was predicted by Starbase 3.0 and verified by the dual luciferase reporter assay, RNA immunoprecipitation (RIP) assay and RNA pull down assay. Xenograft tumor assay was performed to examine the effect of circCSPP1 on tumor growth in vivo. Results The expression of circCSPP1 and FZD7 was upregulated while miR-944 expression was downregulated in doxorubicin (DOX)-resistant CRC tissues and cells. CircCSPP1 knockdown significantly downregulated enhanced doxorubicin sensitivity, suppressed proliferation, migration, invasion, and induced apoptosis in DOX-resistant CRC cells. Interestingly, we found that circCSPP1 directly downregulated miR-944 expression and miR-944 decreased FZD7 level through targeting to 3′ untranslated region (UTR) of FZD7. Furthermore, circCSPP1 mediated DOX-resistant CRC cell progression and doxorubicin sensitivity by regulating miR-944/FZD7 axis. Besides, circCSPP1 downregulation dramatically repressed CRC tumor growth in vivo. Conclusion Our data indicated that circCSPP1 knockdown inhibited DOX-resistant CRC cell growth and enhanced doxorubicin sensitivity by miR-944/FZD7 axis, providing a potential target for CRC therapy.

LncRNA HCG18 suppresses CD8+ T cells to confer resistance to cetuximab in colorectal cancer via miR-20b-5p/PD-L1 axis

Epigenomics ◽  
2021 ◽  
Author(s):  
Yan-Jie Xu ◽  
Jie-Min Zhao ◽  
Xue-Feng Ni ◽  
Wei Wang ◽  
Wen-Wei Hu ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Cd8 T Cells ◽  
Noncoding Rna ◽  
Luciferase Assay ◽  
Immunoprecipitation Assay ◽  
Gene And Protein Expression ◽  
Proliferation And Apoptosis ◽  
Rna Immunoprecipitation ◽  
Relative Gene

Aim: We aimed to explore the effect of long noncoding RNA HCG18 in colorectal cancer (CRC). Materials & methods: Relative gene and protein expression were screened. Colony formation and flow cytometry assays were performed to determine proliferation and apoptosis. Dual luciferase assay and RNA immunoprecipitation assay were conducted to validate the interaction between indicated molecules. Xenograft in nude mice was applied to verify the conclusion in vivo. Results: HCG18 and PD-L1 were upregulated while miR-20b-5p was downregulated in CRC tissue. Functional analysis revealed that lncRNA HCG18 promoted proliferation, migration and resistance to cetuximab of CRC cells via miR-20b-5p/PD-L1 axis. Conclusion: HCG18 facilitated the progress of tumor, conferred to cetuximab resistance and suppressed CD8+ T cell via miR-20b-5p/PD-L1 axis.

scholarly journals miR-125 inhibits colorectal cancer proliferation and invasion by targeting TAZ

2019 ◽  
Vol 39 (12) ◽  
Author(s):  
Meiyuan Yang ◽  
Xiaoli Tang ◽  
Zheng Wang ◽  
Xiaoqing Wu ◽  
Dong Tang ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Cancer Progression ◽  
Underlying Mechanism ◽  
Cell Counting ◽  
Binding Motif ◽  
Cancer Proliferation ◽  
Qrt Pcr ◽  
Sirna Knockdown ◽  
Proliferation And Invasion ◽  
Hct116 Cells

Abstract Colorectal cancer (CRC) is the third most common malignant tumor worldwide and is a serious threat to human health. MicroRNAs (miRNAs) play a key role in oncogenesis and cancer progression. MiRNA-125 (miR-125) is an important miRNA that is dysregulated in several kinds of cancers. Thus, we investigated the expression and effects of miR-125 and Transcriptional co-activator with PDZ-binding motif (TAZ) for a better understanding of the underlying mechanism of tumor progression in CRC, which may provide an emerging biomarker for diagnosis and treatment of CRC. We measured the expression levels of miR-125 in CRC tissues, adjacent tissues, and cell lines (e.g. HCT116, SW480, FHC) by quantitative real-time polymerase chain reaction (qRT-PCR). The effect of miR-125 on proliferation and invasion in CRC cells was detected by Cell Counting Kit-8 (CCK-8), clone formation assay, and transwell assay. Western blotting and qRT-PCR were used to investigate the expression of TAZ after knocking down miR-125 in HCT116 cells or overexpressing miR-125 in SW480 cells. MiR-125 was significantly down-regulated in CRC compared with pericarcinomatous tissue from 18 patients. An miR-125 inhibitor promoted CRC cell proliferation and invasion, while miR-125 mimic had the opposite effect. Moreover, we found that TAZ was an miR-125 target and the siRNA knockdown of TAZ could reverse the effect of the miR-125 inhibitor on proliferation and invasion in HCT116 cells. The present study shows that miR-125 suppresses CRC proliferation and invasion by targeting TAZ.

Long Noncoding RNA TTC39A-AS1 Promotes Breast Cancer Tumorigenicity by Sponging MicroRNA-483-3p and Thereby Upregulating MTA2

Pharmacology ◽  
2021 ◽  
pp. 1-15
Author(s):  
Zhaohui Zhou ◽  
Ping Yang ◽  
Binming Zhang ◽  
Maohui Yao ◽  
Yali Jia ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Noncoding Rna ◽  
Flow Cytometric Analysis ◽  
The Cancer Genome Atlas ◽  
Cell Counting ◽  
Luciferase Reporter ◽  
Migration And Invasion ◽  
Rna Immunoprecipitation ◽  
Anticancer Treatment ◽  
High Level

<b><i>Introduction:</i></b> In recent years, the regulatory activities of long noncoding RNAs have received increasing attention as an important research focus. This study aimed to characterize the expression and detailed roles of TTC39A antisense RNA 1 (TTC39A-AS1) in breast cancer (BC), in addition to concentrating on its downstream mechanisms. <b><i>Methods:</i></b> Quantitative RT-PCR was performed to determine the expression levels of TTC39A-AS1, microRNA-483-3p (miR-483-3p), and metastasis-associated gene 2 (MTA2). Further, the detailed functions of TTC39A-AS1 in BC cells were confirmed using the Cell Counting Kit 8 assay, flow cytometric analysis, and Transwell cell migration and invasion assays. The targeting relationship between TTC39A-AS1, miR-483-3p, and MTA2 in BC was predicted via bioinformatics analysis and further confirmed by performing the luciferase reporter assay and RNA immunoprecipitation. <b><i>Results:</i></b> TTC39A-AS1 was present in high levels in BC; this result was confirmed in our sample cohort and The Cancer Genome Atlas database. Patients with BC with a high level of TTC39A-AS1 had a shorter overall survival than those with a low level of TTC39A-AS1. Functionally, the absence of TTC39A-AS1 accelerated cell apo­ptosis but retained cell proliferation, migration, and invasion. Mechanistically, TTC39A-AS1 functioned as a competing endogenous RNA in BC by sponging miR-483-3p and thereby indirectly increasing MTA2 expression. Finally, rescue experiments revealed that the tumor-inhibiting actions of TTC39A-AS1 knockdown on the malignant characteristics of BC cells could be reversed by inhibiting miR-483-3p or upregulating MTA2. <b><i>Conclusion:</i></b> The newly identified TTC39A-AS1/miR-483-3p/MTA2 pathway was revealed to be a critical regulator in the tumorigenicity of BC, possibly offering a novel therapeutic direction for the anticancer treatment of BC.

scholarly journals CircHMGCS1 is upregulated in colorectal cancer and promotes proliferation of colorectal cancer cells by targeting microRNA-503-5p

2019 ◽  
Vol 17 ◽  
pp. 205873921986955 ◽  
Author(s):  
Jingqing Dong ◽  
Jun Li ◽  
Jihui Luo ◽  
Weiqiang Wu
Keyword(s):  
Colorectal Cancer ◽  
Cell Proliferation ◽  
Quantitative Polymerase Chain Reaction ◽  
Clinical Parameter ◽  
Cell Counting ◽  
Migration And Invasion ◽  
Apoptosis Pathway ◽  
Colorectal Cancer Cells ◽  
And Migration ◽  
Related Proteins

This study aims to explore the regulatory mechanism of circHMGCS1/microRNA-503-5p (miR-503-5p) axis during colorectal cancer (CRC) development and progression. Real-time quantitative polymerase chain reaction (RT-qPCR) was applied to evaluate the expression of circHMGCS1 and miR-503-5p in CRC samples and their adjacent non-tumor specimen. Then, cell proliferation and cell apoptosis and migration and invasion of circHMGCS1-knocked down cells were further detected, using cell counting kit-8 (CCK-8), flow cytometry, Transwell assay, and western blotting assays. CircHMGCS1 was found to be significantly upregulated in CRC, and its high expression was closely correlated with the poor clinical parameter. In addition, the knockdown of circHMGCS1 could significantly inhibit CRC cells’ growth promoting apoptosis, as suggested by the expression of apoptosis pathway-related proteins, which changed consistently. Furthermore, miR-503-5p inhibitors were able to reverse the suppression of cell proliferation induced by silencing circHMGCS1. Therefore, circHMGCS1 might serve as a promising bio-marker and treatment target for CRC.

scholarly journals CircSEC24A upregulates TGFBR2 expression to accelerate pancreatic cancer proliferation and migration via sponging to miR-606

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yankun Chen ◽  
Simiao Xu ◽  
Xinyuan Liu ◽  
Xueyi Jiang ◽  
Jianxin Jiang
Keyword(s):  
Pancreatic Cancer ◽  
Cell Lines ◽  
Circular Rna ◽  
Luciferase Reporter ◽  
Cancer Proliferation ◽  
Diagnosis And Prognosis ◽  
Pancreatic Cancer Cells ◽  
Invasive Capacity ◽  
And Migration ◽  
Cancer Tissues

Abstract Background Circular RNA (circRNA), producing by special selective splicing, was widely expressed in the cytoplasm of eukaryotic cells as a newly non-coding RNAs. It played different roles in a variety of diseases including cancer and performed different functions. Nonetheless, reports on the specific function of circRNA in pancreatic cancer (PC) were still rarely so far. In particular, the role of circSEC24A in PC remains unclear. Methods Real-time fluorescent quantitative PCR was used to evaluate the expression level of circSEC24A in pancreatic cancer tissues and cell lines. Furthermore, we used some functional experiments, such as EDU and Transwell assays, to explore the effects of circSEC24A on the proliferation and invasiveness of pancreatic cancer. Finally, the corresponding relationship among circSEC24A, miR-606 and TGFBR2 was explored by dual luciferase reporter and other mechanism studies. Results The expression of circSEC24A in both pancreatic cancer tissues and cell lines was evidently up-regulated. Furthermore, knockdown of circSEC24A significantly inhibited the proliferative, migration and invasive capacity of pancreatic cancer cells, whereas miR-606 inhibitor obviously counteracted these effects. Further study confirmed that circSEC24A alleviated suppression on target TGFBR2 expression by directly sponging miR-606 and then influenced the tumorigenesis of pancreatic cancer. Conclusions These findings indicated that the progression of pancreatic cancer can be driven by circSEC24A influencing miR-606/TGFBR2 axis. Therefore, circSEC24A might be used as a critical biomarker influencing the early diagnosis and prognosis of pancreatic cancer.

scholarly journals Ginsenoside Rg3 alleviates septic liver injury by regulating the lncRNA TUG1/miR-200c-3p/SIRT1 axis

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Pan Wu ◽  
Xiao Yu ◽  
Yue Peng ◽  
Qian-Lu Wang ◽  
Long-Tian Deng ◽  
...  
Keyword(s):  
Liver Injury ◽  
Mitochondrial Dysfunction ◽  
Noncoding Rna ◽  
Protective Role ◽  
Cell Counting ◽  
Luciferase Reporter ◽  
Ampk Pathway ◽  
Rna Immunoprecipitation ◽  
Hepatocyte Damage ◽  
Amp Activated Protein Kinase

Abstract Background Studies have shown that ginsenoside R3 (Rg3) plays a protective role in sepsis-induced organ injuries and mitochondrial dysfunction. Long noncoding RNA (lncRNA) taurine-upregulated gene 1 (TUG1) is regarded as a regulator in sepsis. However, the association between TUG1 and Rg3 remains elusive. Methods A sepsis mouse model was established by caecal ligation and puncture (CLP), and liver injury was induced by haematoxylin-eosin (H&E) staining. Lipopolysaccharide (LPS) was used to induce hepatocyte damage. The expression levels of TUG1, microRNA (miR)-200a-3p, and silencing information regulator 1 (SIRT1) were examined by quantitative real-time polymerase chain reaction (qRT–PCR) assays. Cell viability was monitored using the Cell Counting Kit-8 (CCK-8) assay. MitoSOX Red staining and CBIC2 (JC-1) dye were employed to detect mitochondrial reactive oxygen species (ROS) and mitochondrial transmembrane potential (MTP) levels, respectively. The interaction between miR-200a-3p and TUG1 or SIRT1 was confirmed via dual-luciferase reporter or RNA immunoprecipitation (RIP) assay. Results Rg3 upregulated TUG1 expression in liver tissues of CLP mice and LPS-induced hepatocytes. Rg3 could activate autophagy to improve mitochondrial dysfunction in LPS-treated hepatocytes, which was partially reversed by TUG1 depletion or miR-200a-3p overexpression. Importantly, TUG1 targeted miR-200a-3p to activate the SIRT1/AMP-activated protein kinase (AMPK) pathway in LPS-treated hepatocytes. Moreover, gain of TUG1 ameliorated mitochondrial dysfunction in LPS-treated hepatocytes by sequestering miR-200a-3p. Conclusion Our study revealed that Rg3 increased TUG1 expression and reduced miR-200a-3p expression to stimulate the SIRT1/AMPK pathway, thereby enhancing autophagy to improve sepsis-induced liver injury and mitochondrial dysfunction.

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