Background:Circular RNAs(circRNAs)generated by back-splicing of precursor mRNAs(pre-mRNAs)are often aberrantly expressed in cancer cells.Accumulating evidence has revealed that circRNAs play a critical role in the pro...Background:Circular RNAs(circRNAs)generated by back-splicing of precursor mRNAs(pre-mRNAs)are often aberrantly expressed in cancer cells.Accumulating evidence has revealed that circRNAs play a critical role in the progression of several cancers,including colorectal cancer(CRC).However,the current understandings of the emerging functions of circRNAs in CRC lipid metabolism and the underlying molecular mechanisms are still limited.Here,we aimed to explore the role of circCAPRIN1 in regulating CRC lipid metabolism and tumorigenesis.Methods:circRNA microarray was performed with three pairs of tumor and non-tumor tissues from CRC patients.The expression of circRNAs were determined by quantitative PCR(qPCR)and in situ hybridization(ISH).The endogenous levels of circRNAs in CRC cells were manipulated by transfection with lentiviruses overexpressing or silencing circRNAs.The regulatory roles of circRNAs in the occurrence of CRC were investigated both in vitro and in vivo using gene expression array,RNA pull-down/mass spectrometry,RNA immunoprecipitation assay,luciferase reporter assay,chromatin immunoprecipitation analysis,and fluorescence in situ hybridization(FISH).Results:Among circRNAs,circCAPRIN1 was most significantly upregulated in CRC tissue specimens.circCAPRIN1 expression was positively correlated with the clinical stage and unfavorable prognosis of CRC patients.Downregulation of circCAPRIN1 suppressed proliferation,migration,and epithelial-mesenchymal transition of CRC cells,while circCAPRIN1 overexpression had opposite effects.RNA sequencing and gene ontology analysis indicated that circCAPRIN1 upregulated the expressions of genes involved in CRC lipid metabolism.Moreover,circCAPRIN1 promoted lipid synthesis by enhancing Acetyl-CoA carboxylase 1(ACC1)expression.Further mechanistic assays demonstrated that circCAPRIN1 directly bound signal transducer and activator of transcription 2(STAT2)to activate ACC1 transcription,thus regulating lipid metabolism and facilitating CRC tumorigenesis.Conclusions:These findings revealed the oncogenic role and mechanism of circCAPRIN1 in CRC.circCAPRIN1 interacted with STAT2 to promote CRC tumor progression and lipid synthesis by enhancing the expression of ACC1.circCAPRIN1 may be considered as a novel potential diagnostic and therapeutic target for CRC patients.展开更多
以不同性别类型的黄瓜高代自交系为材料,根据GenBank中提供的乙烯合成、信号转导有关基因序列、花器官发育相关的黄瓜性别决定蛋白基因、AGMOUS同源异型基因、与性别表达相关的RAPD和ISSR引物,采用Primer Premier 5.00专业引物设计软件...以不同性别类型的黄瓜高代自交系为材料,根据GenBank中提供的乙烯合成、信号转导有关基因序列、花器官发育相关的黄瓜性别决定蛋白基因、AGMOUS同源异型基因、与性别表达相关的RAPD和ISSR引物,采用Primer Premier 5.00专业引物设计软件,设计可能与性别表达有关特异引物.结果表明,ACS1号引物对(ACS-F1,5′-ATTCAGATGGGT-3′;ACCS-R1,5′-GCCAAAGCTCGACAT-3′),CsACS1G-SCAR引物对(ACS-F1,5′-TTAACTACTTCGGACGGGCATAG-3′;ACCS-R1,5′-AGGTGTTCAGCAAA CATAGGGTG-3′)及RAPD引物S12对不同性别类型的黄瓜基因组DNA的PCR扩增产物表现出明显的多态性.用Mapmaker/Exp 3.0进行连锁分析,发现雌性F基因和ACS_280,CsACS1G-SCAR_430均连锁群,遗传距离分别为31.4,10.0 cM,与S12_280标记不在一个连锁群上.展开更多
基金National Natural Science Foundation of China,Grant/Award Numbers:81972260,82103259Shanghai Municipal Natural Science Foundation,Grant/Award Number:21ZR1414400Shanghai Medical Innovation Research Project,Grant/Award Number:22Y11907600。
文摘Background:Circular RNAs(circRNAs)generated by back-splicing of precursor mRNAs(pre-mRNAs)are often aberrantly expressed in cancer cells.Accumulating evidence has revealed that circRNAs play a critical role in the progression of several cancers,including colorectal cancer(CRC).However,the current understandings of the emerging functions of circRNAs in CRC lipid metabolism and the underlying molecular mechanisms are still limited.Here,we aimed to explore the role of circCAPRIN1 in regulating CRC lipid metabolism and tumorigenesis.Methods:circRNA microarray was performed with three pairs of tumor and non-tumor tissues from CRC patients.The expression of circRNAs were determined by quantitative PCR(qPCR)and in situ hybridization(ISH).The endogenous levels of circRNAs in CRC cells were manipulated by transfection with lentiviruses overexpressing or silencing circRNAs.The regulatory roles of circRNAs in the occurrence of CRC were investigated both in vitro and in vivo using gene expression array,RNA pull-down/mass spectrometry,RNA immunoprecipitation assay,luciferase reporter assay,chromatin immunoprecipitation analysis,and fluorescence in situ hybridization(FISH).Results:Among circRNAs,circCAPRIN1 was most significantly upregulated in CRC tissue specimens.circCAPRIN1 expression was positively correlated with the clinical stage and unfavorable prognosis of CRC patients.Downregulation of circCAPRIN1 suppressed proliferation,migration,and epithelial-mesenchymal transition of CRC cells,while circCAPRIN1 overexpression had opposite effects.RNA sequencing and gene ontology analysis indicated that circCAPRIN1 upregulated the expressions of genes involved in CRC lipid metabolism.Moreover,circCAPRIN1 promoted lipid synthesis by enhancing Acetyl-CoA carboxylase 1(ACC1)expression.Further mechanistic assays demonstrated that circCAPRIN1 directly bound signal transducer and activator of transcription 2(STAT2)to activate ACC1 transcription,thus regulating lipid metabolism and facilitating CRC tumorigenesis.Conclusions:These findings revealed the oncogenic role and mechanism of circCAPRIN1 in CRC.circCAPRIN1 interacted with STAT2 to promote CRC tumor progression and lipid synthesis by enhancing the expression of ACC1.circCAPRIN1 may be considered as a novel potential diagnostic and therapeutic target for CRC patients.
