scholarly journals CircRNA PIP5K1A promotes the progression of glioma through upregulation of TCF12/PI3K/AKT pathway by sponging miR-515-5p

2020 ◽  
Author(s):  
Kebin Zheng ◽  
Haipeng Xie ◽  
Xiaosong Wu ◽  
Xichao Wen ◽  
Zhaomu Zeng ◽  
...  

Abstract BackgroundIncreasing studies have revealed that circular RNAs (CircRNAs) make great contribution to regulating tumor progression. Therefore, we intended to explore the expression characteristics, function, and related mechanisms of a novel type of circRNA, PIP5K1A in glioma. MethodsFirstly, RT-PCR was carried out to examine CircPIP5K1A expression in glioma tissues and adjacent normal tissues, and the correlation between CircPIP5K1A level and the clinical pathological indicators of glioma was analyzed. Then, the CircPIP5K1A expression in various glioma cell lines was detected, and a cell model of CircPIP5K1A overexpression and knockdown was constructed. Subsequently, cell proliferation and viability were detected by CCK8 method and BrdU staining, apoptosis was detected by flow cytometry, and cell invasion was examined by Transwell assay. The expression of TCF12, PI3K/AKT pathway apoptotic related proteins (including Caspase3, Bax and Bcl2) and epithelial-mesenchymal transition (EMT) markers (including E-cadherin, Vimentin and N-cadherin) by western blot or RT-PCR. ResultsThe results manifested that CircPIP5K1A was obviously upregulated in glioma tissues (compared with that in normal adjacent tissues), and overexpressed CircPIP5K1A was distinctly related to glioma volume and histopathological grade. Functionally, overexpressing CircPIP5K1A notably elevated the proliferation, invasion, EMT of glioma cells, and inhibited apoptosis both in vivo and in vitro. Besides, CircPIP5K1A also upregulated TCF12 and PI3K/AKT pathway activation. Bioinformatics analysis testified that miR-515-5p was a common target of CircPIP5K1A and TCF12, while dual luciferase reporter assay and RNA immunocoprecipitation (RIP) experiment further confirmed that CircPIP5K1A targeted miR-515-5p, which bound the 3'-untranslated region (UTR) of TCF12. ConclusionsAltogether, the study illustrated that CircPIP5K1A is a potential prognostic marker in glioma and regulates the development of glioma through the modulating miR-515-5p mediated TCF12/PI3K/AKT axis.

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Kebin Zheng ◽  
Haipeng Xie ◽  
Wensong Wu ◽  
Xichao Wen ◽  
Zhaomu Zeng ◽  
...  

Abstract Background Increasing studies have revealed that circular RNAs (CircRNAs) make great contributions to regulating tumor progression. Therefore, we intended to explore the expression characteristics, function, and related mechanisms of a novel type of circRNA, PIP5K1A, in glioma. Methods Firstly, reverse transcription-polymerase chain reaction (RT-PCR) was carried out to examine CircPIP5K1A expression in glioma tissues and adjacent normal tissues, and the correlation between CircPIP5K1A level and the clinical-pathological indicators of glioma was analyzed. Then, the CircPIP5K1A expression in various glioma cell lines was detected, and CircPIP5K1A overexpression and knockdown cell models were constructed. Subsequently, cell proliferation and viability were detected by the CCK8 method and BrdU staining. Cell apoptosis was detected by flow cytometry, and cell invasion was examined by Transwell assay. The expression of TCF12, PI3K/AKT pathway apoptotic related proteins (Caspase3, Bax, and Bcl2) and epithelial-mesenchymal transition (EMT) markers (E-cadherin, Vimentin, and N-cadherin) was determined by western blot or RT-PCR. Results The results manifested that CircPIP5K1A was upregulated in glioma tissues (compared with that in normal adjacent tissues), and overexpressed CircPIP5K1A was related to glioma volume and histopathological grade. Functionally, overexpressing CircPIP5K1A notably elevated glioma cell proliferation, invasion, and EMT and inhibited apoptosis both in vivo and in vitro. Besides, CircPIP5K1A upregulated TCF12 and PI3K/AKT activation. Bioinformatics analysis testified that miR-515-5p was a common target of CircPIP5K1A and TCF12, while the dual-luciferase reporter assay and RNA immunoprecipitation (RIP) experiment further confirmed that CircPIP5K1A targeted miR-515-5p, which bound the 3′-untranslated region (UTR) of TCF12. Conclusions Overall, the study illustrated that CircPIP5K1A is a potential prognostic marker in glioma and regulates glioma evolvement by modulating the miR-515-5p-mediated TCF12/PI3K/AKT axis.


2020 ◽  
Author(s):  
Xinglong Dai ◽  
Jianjun Liu ◽  
Xiong Guo ◽  
Anqi Cheng ◽  
Xiaoya Deng ◽  
...  

Background: Mounting evidence has displayed critical roles of circular RNAs (circRNAs) in multiple cancers. The underlying mechanisms by which circFGD4 contributed to gastric cancer (GC) are still unclear. Methods: The levels and clinical values of circFGD4 in GC patients were detected and analysed by quantitative real-time PCR. The biological roles of circFGD4 in GC were assessed in vitro and in vivo experiments. Dual-luciferase reporter, fluorescence in situ hybridization, RNA immunoprecipitation, biotin-coupled RNA pull-down, and TOP/Flash and FOP/Flash reporter gene assays were employed to evaluate the effects of circFGD4 on miR-532-3p-mediated adenomatous polyposis coli (APC)/β-catenin signalling in GC cells. Results: circFGD4 expression was down-regulated the most in human GC tissues and cell lines. Low expression of circFGD4 was correlated with poor tumour differentiation, lymphatic metastasis, and poor prognosis of GC patients. circFGD4 suppressed GC cell viability, colony formation, migration, induced epithelial-mesenchymal transition (EMT) and tumorigenesis and metastasis in vivo. Next, we validated that circFGD4 acted as a sponge of miR-532-3p to relieve the tumour-promoting effects of miR-532-3p on its target APC. The mechanistic analysis demonstrated that the circFGD4 suppressed GC cell viability, migration, and EMT by modulating the miR-532-3p/APC axis to inactivate the β-catenin signalling. Conclusion: circFGD4 suppressed GC progression through sponging miR-532-3p and enhancing APC expression to inactivate the β-catenin signalling. Thus circFGD4 provides a novel potential biomarker and valuable therapeutic strategy for GC.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Guili Xu ◽  
Peng Zhang ◽  
Hansi Liang ◽  
Yunhua Xu ◽  
Jian Shen ◽  
...  

Abstract Background Epithelial-mesenchymal transition (EMT) has been associated with wound healing, tumorigenesis, and metastasis. Circular RNAs (circRNAs) are functional non-coding RNAs involved in multiple human cancers. However, whether and how circRNAs contribute to the EMT in hepatocellular carcinomas (HCC) remains to be deciphered. In this study, we investigated the regulation and function of hsa_circ_0003288 on programmed death-1 ligand 1 (PD-L1) during EMT and HCC invasiveness. Methods Hsa_circ_0003288 expression was measured by real-time quantitative reverse transcriptase PCR (qRT-PCR). Luciferase reporter assays, RNA pull-down assay and fluorescence in situ hybridization (FISH) were used to determine the correlation between hsa_circ_0003288 and miR-145 and between miR-145 and PD-L1. Furthermore, ectopic overexpression and siRNA-mediated downregulation of hsa_circ_0003288, transwell assays, and in vivo studies were used to determine the function of hsa_circ_0003288 on the EMT and invasiveness of L02 and HCC cells. Results miR-145 directly targeted the PD-L1 3′-untranslated region (UTR) region, and hsa_circ_0003288 acted as a miR-145 sponge to regulate PD-L1 expression. Overexpression of hsa_circ_0003288 increased PD-L1 levels and promoted EMT, migration, and invasiveness of L02 cells. These observations were reversed after knockdown of hsa_circ_0003288 in HepG2 and Huh7 cells. Overexpression of PD-L1 rescued EMT, migration, and invasiveness of HepG2 and Huh7 cells after knockdown of hsa_circ_0003288. Furthermore, hsa_circ_0003288 knockdown reduced EMT in in vivo studies. Hsa_circ_0003288/PD-L1 axis was found to mediate the metastatic phenotypes via the PI3K/Akt pathway in HCC. Additionally, expression levels of hsa_circ_0003288 were increased and positively correlated with PD-L1 expression in HCC tissues. Conclusion Our findings demonstrated that hsa_circ_0003288 promoted EMT and invasion of HCC via the hsa_circ_0003288/miR-145/PD-L1 axis through the PI3K/Akt pathway. Targeting hsa_circ_0003288 may be a therapeutic strategy for the treatment of HCC.


Author(s):  
Lili Zhao ◽  
Yao Zhang ◽  
Jiaoxia Liu ◽  
Wei Yin ◽  
Dan Jin ◽  
...  

MicroRNAs (miRNAs) are short endogenous noncoding RNAs that frequently play vital roles in many cancer types. Herein we demonstrated that miR-185 was remarkably downregulated in NSCLC tissues compared with adjacent normal tissues. A lower level of miR-185 was associated with lymph node metastasis. Functional assays showed that upregulation of miR-185 inhibited the proliferation, colony formation, and invasion capacities of NSCLC cells in vitro. Furthermore, we found that miR-185 suppressed the epithelial‐mesenchymal transition (EMT) process. Bioinformatics analysis and luciferase reporter gene assays revealed that Kruppel-like factor 7 (KLF7) was the target of miR-185. Overexpression of miR-185 reduced the expression of KLF7 in NSCLC cells. Upregulation of KLF7 partly neutralized the inhibitory effects of miR-185 on the proliferation and invasion of NSCLC. Additionally, we confirmed that miR-185 suppressed the tumor growth of NSCLC A549 cells in vivo. Taken together, these results demonstrate that miR-185 acts as a suppressor by targeting KLF7 in NSCLC.


2021 ◽  
Vol 11 ◽  
Author(s):  
Qian Shen ◽  
Gang Zheng ◽  
Yi Zhou ◽  
Jin Tong ◽  
Sanpeng Xu ◽  
...  

BackgroundCircular RNAs (circRNAs) is a novel class of non-coding RNAs that regulate gene expression during cancer progression. Circ_0092314 is a newly discovered circRNA that was upregulated in pancreatic cancer (PAAD) tissues. However, the detailed functions and underlying mechanisms of circ_0092314 in PAAD cells remain unclear.MethodsWe first determined the expression of circ_0092314 in PAAD and normal tissues and further investigated the functional roles of circ_0092314 in regulating epithelial-mesenchymal transition (EMT) of PAAD cells. We also assessed the regulatory action of circ_0092314 on the microRNA-671 (miR-671) and its target S100P.ResultsCirc_0092314 was markedly upregulated in PAAD tissues and cells, and its overexpression was closely correlated with worse prognosis of PAAD patients. Functionally, circ_0092314 promotes proliferation, invasion and EMT in vitro and tumor growth in vivo. Mechanistically, we demonstrated that circ_0092314 directly binds to miR-671 and relieve its suppression of the downstream target S100P, which induces EMT and activates the AKT signaling pathway. The tumor-promoting effects caused by overexpression of circ_0092314 could be revered by re-expression of miR-671 in PAAD cells.ConclusionsOverall, our study demonstrates that circ_0092314 exerts critical roles in promoting the EMT features of PAAD cells, and provides insight into how elevated expression of circ_0092314 might influence PAAD progression.


2021 ◽  
Vol 12 (4) ◽  
Author(s):  
Zhongjian Yu ◽  
Xiongjie Zhu ◽  
Ying Li ◽  
Min Liang ◽  
Meijun Liu ◽  
...  

AbstractLung adenocarcinoma (LUAD) has high incidence and mortality rates worldwide; however, its detailed molecular pathology remains unclear. Although circRNAs have gradually been identified as molecules that are differentially expressed in tumors and play key roles in tumor progression, their role in LUAD is poorly understood. Through microarray analysis, we obtained the circRNA expression profile of LUAD and found that circ-HMGA2 (hsa_circ_0027446), a novel RNA, is highly expressed in LUAD. The high expression of circ-HMGA2 was further verified in 36 paired LUAD and adjacent normal tissues. Functionally, circ-HMGA2 promoted LUAD cell metastasis in vitro and in vivo. The luciferase reporter assay and FISH results showed that circ-HMGA2 interacts with miR-1236-3p and that miR-1236-3p interacts with ZEB1. In addition, miR-1236-3p was expressed at low levels in LUAD, inhibited LUAD cell metastasis, and suppressed the function of circ-HMGA2. ZEB1 is an EMT-promoting transcription factor. The PCR and WB analysis results showed that circ-HMGA2 promotes both ZEB1 expression and EMT. MiR-1236-3p had the opposite effect, reversing the promotive effect of circ-HMGA2 on EMT. In summary, circ-HMGA2 promotes LUAD cell metastasis through the miR-1236-3p/EMT axis, indicating that it could be a therapeutic target in LUAD.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Lei Wang ◽  
Yehui Zhou ◽  
Liang Jiang ◽  
Linlin Lu ◽  
Tiantian Dai ◽  
...  

Abstract Background Chemotherapeutic resistance is the main cause of clinical treatment failure and poor prognosis in triple-negative breast cancer (TNBC). There is no research on chemotherapeutic resistance in TNBC from the perspective of circular RNAs (circRNAs). Methods TNBC-related circRNAs were identified based on the GSE101124 dataset. Quantitative reverse transcription PCR was used to detect the expression level of circWAC in TNBC cells and tissues. Then, in vitro and in vivo functional experiments were performed to evaluate the effects of circWAC in TNBC. Results CircWAC was highly expressed in TNBC and was associated with worse TNBC patient prognosis. Subsequently, it was verified that downregulation of circWAC can increase the sensitivity of TNBC cells to paclitaxel (PTX) in vitro and in vivo. The expression of miR-142 was negatively correlated with circWAC in TNBC. The interaction between circWAC and miR-142 in TNBC cells was confirmed by RNA immunoprecipitation assays, luciferase reporter assays, pulldown assays, and fluorescence in situ hybridization. Mechanistically, circWAC acted as a miR-142 sponge to relieve the repressive effect of miR-142 on its target WWP1. In addition, the overall survival of TNBC patients with high expression of miR-142 was significantly better than that of patients with low expression of miR-142, and these results were verified in public databases. MiR-142 regulated the expression of WWP1 and the activity of the PI3K/AKT pathway. It was confirmed that WWP1 is highly expressed in TNBC and that the prognosis of patients with high WWP1 expression is poor. Conclusions CircWAC/miR-142/WWP1 form a competing endogenous RNA (ceRNA) network to regulate PI3K/AKT signaling activity in TNBC cells and affect the chemosensitivity of cells.


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Jiajia Jiang ◽  
Rong Li ◽  
Junyi Wang ◽  
Jie Hou ◽  
Hui Qian ◽  
...  

Circular RNA CDR1as has been demonstrated to participate in various cancer progressions as miRNA sponges. The exact underlying mechanisms of CDR1as on gastric cancer (GC) metastasis remain unknown. Here, we found that CDR1as knockdown facilitated GC cell migration and invasion while its overexpression inhibited the migration and invasion abilities of GC cells in vitro and in vivo. Moreover, epithelial-mesenchymal transition- (EMT-) associated proteins and MMP2 and MMP9 were downregulated by CDR1as. Bioinformatics analysis combined with dual-luciferase reporter gene assays, western blot, RT-qPCR analysis, and functional rescue experiments demonstrated that CDR1as served as a miR-876-5p sponge and upregulated the target gene GNG7 expression to suppress GC metastasis. In summary, our findings indicate that CDR1as suppresses GC metastasis through the CDR1as/miR-876-5p/GNG7 axis.


Cancers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 735 ◽  
Author(s):  
Kwang Seock Kim ◽  
Dongjun Jeong ◽  
Ita Novita Sari ◽  
Yoseph Toni Wijaya ◽  
Nayoung Jun ◽  
...  

Our current understanding of the role of microRNA 551b (miR551b) in the progression of colorectal cancer (CRC) remains limited. Here, studies using both ectopic expression of miR551b and miR551b mimics revealed that miR551b exerts a tumor suppressive effect in CRC cells. Specifically, miR551b was significantly downregulated in both patient-derived CRC tissues and CRC cell lines compared to normal tissues and non-cancer cell lines. Also, miR551b significantly inhibited the motility of CRC cells in vitro, including migration, invasion, and wound healing rates, but did not affect cell proliferation. Mechanistically, miR551b targets and inhibits the expression of ZEB1 (Zinc finger E-box-binding homeobox 1), resulting in the dysregulation of EMT (epithelial-mesenchymal transition) signatures. More importantly, miR551b overexpression was found to reduce the tumor size in a xenograft model of CRC cells in vivo. Furthermore, bioinformatic analyses showed that miR551b expression levels were markedly downregulated in the advanced-stage CRC tissues compared to normal tissues, and ZEB1 was associated with the disease progression in CRC patients. Our findings indicated that miR551b could serve as a potential diagnostic biomarker and could be utilized to improve the therapeutic outcomes of CRC patients.


2020 ◽  
Author(s):  
Wei Zhang ◽  
Bo Wang ◽  
Yang Yang ◽  
Zhen Zhang ◽  
Quan Wang ◽  
...  

Abstract Background circular RNAs (circRNAs) recently have been emerged as vital regulators for involvement of initiation and progression of diverse kinds of human cancers. This study aimed to investigate the role of circRNAs in colorectal cancer (CRC). Methods The expression profile of circRNAs in 5 pairs of CRC tissues and adjacent normal tissues were analyzed by Microarray. Quantitative real-time PCR and in situ hybridization and Base Scope Assay were used to determine the level and prognostic values of hsa_circ_0000231. Then, functional experiments in vitro and in vivo were performed to investigate the effects of hsa_circ_0000231 on cell proliferation. Mechanistically, fluorescent in situ hybridization, dual luciferase reporter assay, RNA pull-down and RNA immunoprecipitation experiments were performed to confirm the interaction between hsa_circ_0000231 and IGF2BP3 or has_miR-375. Results hsa_circ_0000231 was evidently up-regulated in CRC primary tissues, which was indicated to poor prognosis of CRC patients. The results demonstrated that hsa_circ_0000231 could promote CRC cell proliferation as well as tumorigenesis in vitro and in vivo. Mechanistic analysis showed that hsa_circ_0000231 might on the one hand act as a ceRNA (competing endogenous RNA) of miR-375 to regulate cyclin D2 (CCND2), and on the other hand bind to IGF2BP3 protein to protect CCND2 from being degraded. Conclusion Our findings suggest that hsa_circ_0000231 facilitated CRC progression by sponging miR-375 or binding to IGF2BP3 to modulate CCND2. This discovery implied that has_circ_0000231 may be a potential new diagnostic and therapeutic biomarker for CRC.


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