Objective:Pancreatic ductal adenocarcinoma(PDAC)is a disease with high mortality.Many so-called"junk"noncoding RNAs need to be discovered in PDAC.The purpose of this study was therefore to investigate the fu...Objective:Pancreatic ductal adenocarcinoma(PDAC)is a disease with high mortality.Many so-called"junk"noncoding RNAs need to be discovered in PDAC.The purpose of this study was therefore to investigate the function and regulatory mechanism of the long noncoding RNA MEG3 in PDAC.Methods:The Gene Expression Omnibus database(GEO database)was used to determine the differential expression of long noncoding RNAs in PDAC,and MEG3 was selected for subsequent verification.Tissue and cell samples were used to verify MEG3 expression,followed by functional detection in vitro and in vivo.Microarrays were used to characterize long noncoding RNA and mRNA expression profiles.Competing endogenous RNA analyses were used to detect differential MEG3 and relational miRNA expression in PDAC.Finally,promoter analyses were conducted to explain the downregulation of MEG3 PDAC.Results:We generated a catalogue of PDAC-associated long noncoding RNAs in the GEO database.The ectopic expression of MEG3 inhibited PDAC growth and metastasis in vitro and in vivo,which was statistically significant(P<0.05).Microarray analysis showed that multiple microRNAs interacted with MEG3.We also showed that MEG3,as a competing endogenous RNA,directly sponged miR-374a-5p to regulate PTEN expression.The transcription factor,Sp1,recruited EZH2 and HDAC3 to the promoter and transcriptionally repressed MEG3 expression.Finally,clinical data showed that MEG3 and miR-374a-5p expressions were correlated with clinicopathological features.Statistically,Sp1,EZH2,HDAC3,and miR-374 a-5p were negatively correlated with MEG3(P<0.05).Conclusions:Reduced MEG3 levels played a crucial role in the PDAC malignant phenotype,which provided insight into novel and effective molecular targets of MEG3 for pancreatic cancer treatment.展开更多
基金supported in part by the National Natural Science Foundation of China(Grant No.81902372 for Ting Han,81502017 for Feng Jiao,81903062 for Meng Zhuo and 81572315 and 81874048 for Liwei Wang)the Innovation Group Project of Shanghai Municipal Health Commission(Grant No.2019CXJQ03 for Liwei Wang)+2 种基金the State Key Laboratory of Oncogenes and Related Genes(Grant No.90-17-06 for Liwei Wang)the Shanghai Leading Talents Project(Grant No.075 for Liwei Wang)the Shanghai Key Clinical Specialty(Grant No.2018 Oncology for Liwei Wang)。
文摘Objective:Pancreatic ductal adenocarcinoma(PDAC)is a disease with high mortality.Many so-called"junk"noncoding RNAs need to be discovered in PDAC.The purpose of this study was therefore to investigate the function and regulatory mechanism of the long noncoding RNA MEG3 in PDAC.Methods:The Gene Expression Omnibus database(GEO database)was used to determine the differential expression of long noncoding RNAs in PDAC,and MEG3 was selected for subsequent verification.Tissue and cell samples were used to verify MEG3 expression,followed by functional detection in vitro and in vivo.Microarrays were used to characterize long noncoding RNA and mRNA expression profiles.Competing endogenous RNA analyses were used to detect differential MEG3 and relational miRNA expression in PDAC.Finally,promoter analyses were conducted to explain the downregulation of MEG3 PDAC.Results:We generated a catalogue of PDAC-associated long noncoding RNAs in the GEO database.The ectopic expression of MEG3 inhibited PDAC growth and metastasis in vitro and in vivo,which was statistically significant(P<0.05).Microarray analysis showed that multiple microRNAs interacted with MEG3.We also showed that MEG3,as a competing endogenous RNA,directly sponged miR-374a-5p to regulate PTEN expression.The transcription factor,Sp1,recruited EZH2 and HDAC3 to the promoter and transcriptionally repressed MEG3 expression.Finally,clinical data showed that MEG3 and miR-374a-5p expressions were correlated with clinicopathological features.Statistically,Sp1,EZH2,HDAC3,and miR-374 a-5p were negatively correlated with MEG3(P<0.05).Conclusions:Reduced MEG3 levels played a crucial role in the PDAC malignant phenotype,which provided insight into novel and effective molecular targets of MEG3 for pancreatic cancer treatment.
