Summary： This study aimed to examine the effect of long non-coding RNA （LncRNA） MEG3 on the biological behaviors of renal cell carcinoma （RCC） cells 786-0 and the possible mechanism. MEG3 expression levels were d...Summary： This study aimed to examine the effect of long non-coding RNA （LncRNA） MEG3 on the biological behaviors of renal cell carcinoma （RCC） cells 786-0 and the possible mechanism. MEG3 expression levels were detected by RT-qPCR in Rmaor tissues and adjacent non-tumor tissues from 29 RCC patients and in RCC lines 786-0 and SN12 and human embryonic kidney cell line 293T. Plasmids GV144-MEG3 （MEG3 overexpression plasmid） and GV144 （control plasmid） were stably transfected into 786-0 cells by using lipofectamine 2000. Cell viabilities were determined by MTT, cell apoptosis rates by flow cytometry following PE Annexin V and 7AAD staining, apoptosis-related protein expressions by Western blotting, and Bcl-2 mRNA by RT-qPCR in the transfected cells. The results showed that MEG3 was evidently downregulated in RCC tissues （P〈0.05） and RCC cell lines （P〈0.05）. The viabilities of 786-0 cells were decreased significantly after transfection with GV144-MEG3 for over 24 h （P〈0.05）. Consistently, the apoptosis rate was significantly increased in 786-0 cells transfected with GV144-MEG3 for 48 h （P〈0.05）. Furthermore, overexpression of MEG3 could reduce the expression of Bcl-2 and procaspase-9 proteins, enhance the expression of cleaved caspase-9 protein, and promote the release of cytochrome c protein to cytoplasm （P〈0.05）. Additionally, Bcl-2 mRNA level was declined by MEG3 overexpression （P〈0.05）. It was concluded that MEG3 induces the apoptosis of RCC cells possibly by activating the mitochondrial pathway.展开更多
Background:We have shown that downregulation of materally expressed gene 3(MEG3)promoted autophagy and epithelial-mesenchymal transition to promote neuroblastoma(NB)progression.In present study,we aim to further disco...Background:We have shown that downregulation of materally expressed gene 3(MEG3)promoted autophagy and epithelial-mesenchymal transition to promote neuroblastoma(NB)progression.In present study,we aim to further discover the role of MEG3 in NB.Methods:Expression levels of MEG3 in stabled transfected cells were detected by qPCR.Flow cytometry was used to examine the effects of MEG3 overexpression on apoptosis and cell cycle.Moreover,tumor stemness was detected by tumor sphere formation assay.Results:QPCR showed that MEG3 was successfully overexpressed in SK-N-BE(2)C and SK-N-AS cells.CCK8 indicated MEG3 reduced cell proliferation in two NB cells.Flow cytometry revealed that MEG3 promoted apoptosis and caused G0/G1 arrest.Using chromatin isolation by RNA purification(ChIRP)and tumor sphere formation assays,we revealed that upregulation of MEG3 decreased tumor stemness by decreasing Nestin transcription.Conclusions:Overall,present study confirmed an anti-cancer role of MEG3 in NB,demonstrated that MEG3 could be a potential therapeutic target of NB.展开更多
Long non-coding RNAs (lncRNAs) are transcripts longer than 200 nucleotides mostly transcribed by RNA which do not encode proteins. Previously, lncRNAs were considered transcriptional byproducts called “junk DNA” wit...Long non-coding RNAs (lncRNAs) are transcripts longer than 200 nucleotides mostly transcribed by RNA which do not encode proteins. Previously, lncRNAs were considered transcriptional byproducts called “junk DNA” with no biological functions. There are many studies conducted on lncRNAs showing they are actively involved in regulation of epigenetic, transcriptional, and post-transcriptional events. Expressions of lncRNAs are more different in many malignant tumors than in benign tumors and normal tissue. Aberration of lncRNAs is responsible to promote or suppress tumorigenesis and cancer progression. Under different circumstances, lncRNAs exhibit their roles in carcinogenesis such as MALAT1 is responsible for intervening mRNA instability, HOTAIR, MALAT1, ANRIL, PVT1 links with miRNA and histonemodifying complexes, MEG3 associates with miRNA, CCAT2, MEG3, GAS5, UCA1 allies with c-Myc or P53 causing suppression of tumor or oncogenesis. Abnormal expressions of lncRNAs are noticed in gynecological cancers, such as cervical cancer, ovarian cancer, and endometrial cancer. Identification of cervical cancer associated lncRNAs is necessary to understand the molecular biogenesis of cancers. In this review, we summarized the foundation and function of the lncRNAs in terms of tumor progression, invasion, prognosis, apoptosis, metastasis, and chemo-resistance. This review will provide references to determine the clinical applications of lncRNAs as ideal diagnostic biomarkers or therapeutic targets in cervical cancers.展开更多
Objective:This research was performed to explore the effect of macrophage migration inhibitory factor(MIF)on the apoptosis of bone marrow mesenchymal stem cells(BMSCs)in ischemia and hypoxia environments.Methods:The c...Objective:This research was performed to explore the effect of macrophage migration inhibitory factor(MIF)on the apoptosis of bone marrow mesenchymal stem cells(BMSCs)in ischemia and hypoxia environments.Methods:The cell viability of BMSCs incubated under hypoxia/ischemia(H/I)conditions with or without pretreatment with MIF or triglycidyl isocyanurate(TGIC)was detected using cell counting kit-8(CCK-8)analysis.Plasmids containing long noncoding RNA(lncRNA)maternally expressed gene 3(MEG3)orβ-catenin small interfering RNA(siRNA)were used to overexpress or downregulate the corresponding gene,and the p53 signaling pathway was activated by pretreatment with TGIC.The influences of MIF,overexpression of lncRNA MEG3,activation of the p53 signaling pathway,and silencing ofβ-catenin on H/I-induced apoptosis of BMSCs were revealed by western blotting,flow cytometry,and terminal deoxynucleotidyl transferase(TdT)-mediated dUTP nick-end labeling(TUNEL)staining.Results:From the results of CCK-8 assay,western blotting,and flow cytometry,pretreatment with MIF significantly decreased the H/I-induced apoptosis of BMSCs.This effect was inhibited when lncRNA MEG3 was overexpressed by plasmids containing MEG3.The p53 signaling pathway was activated by TGIC,andβ-catenin was silenced by siRNA.From western blot results,the expression levels ofβ-catenin in the nucleus and phosphorylated p53(p-p53)were downregulated and upregulated,respectively,when the lncRNA MEG3 was overexpressed.Through flow cytometry,MIF was also shown to significantly alleviate the increased reactive oxygen species(ROS)level of BMSCs caused by H/I.Conclusions:In summary,we conclude that MIF protected BMSCs from H/I-induced apoptosis by downregulating the lncRNA MEG3/p53 signaling pathway,activating the Wnt/β-catenin signaling pathway,and decreasing ROS levels.展开更多
Background:Long non-codingRNAs(lncRNAs)have been found to be involved in the development of many cancers.In this study,we aimed to identify the molecular mechanisms of lncRNA BAALC antisense RNA 1(BAALC-AS1)in regulat...Background:Long non-codingRNAs(lncRNAs)have been found to be involved in the development of many cancers.In this study,we aimed to identify the molecular mechanisms of lncRNA BAALC antisense RNA 1(BAALC-AS1)in regulating the malignancy of esophageal squamous cell carcinoma(ESCC).Methods:The expression of BAALC-AS1 in cancer patients was analyzed using a tissue microarray.The protein and RNA levels of BAALC-AS1 were determined by Western blotting analysis and quantitative reverse transcription-PCR(RT-qPCR),respectively.The cell proliferation was determined by cell viability assays,bromodeoxyuridine incorporation,and flow cytometry.The relationships among BAALC-AS1,RasGAPSH3 domain-binding protein 2(G3BP2),and c-Myc were determined using RNA immunoprecipitation,RNA pull-down assays,and luciferase assays.Results:The expression of BAALC-AS1 was highly up-regulated and associated with malignant phenotypes in ESCC tissues and cell lines.In vivo and in vitro assays showed that BAALC-AS1 promoted ESCC cell proliferation,migration,and invasion.BAALC-AS1 directly interacted with G3BP2,and thereby inhibited the degradation of c-Myc RNA 3’-UTR by G3BP2,thus leading to the accumulation of c-Myc expression.Additionally,c-Myc acted as a transcription factor that can induce the expression of BAALC-AS1 by directly binding to its promoter region.Conclusions:BAALC-AS1/G3BP2/c-Myc feedback loop plays a critical role in the development of ESCC,which might provide a novel therapeutic target and facilitate the development of new therapeutic strategies for the treatment of ESCC.展开更多
基金supported by grants from the National Natural Science Foundation of China(Nos.81001132,81172423,and 81272816)
文摘Summary： This study aimed to examine the effect of long non-coding RNA （LncRNA） MEG3 on the biological behaviors of renal cell carcinoma （RCC） cells 786-0 and the possible mechanism. MEG3 expression levels were detected by RT-qPCR in Rmaor tissues and adjacent non-tumor tissues from 29 RCC patients and in RCC lines 786-0 and SN12 and human embryonic kidney cell line 293T. Plasmids GV144-MEG3 （MEG3 overexpression plasmid） and GV144 （control plasmid） were stably transfected into 786-0 cells by using lipofectamine 2000. Cell viabilities were determined by MTT, cell apoptosis rates by flow cytometry following PE Annexin V and 7AAD staining, apoptosis-related protein expressions by Western blotting, and Bcl-2 mRNA by RT-qPCR in the transfected cells. The results showed that MEG3 was evidently downregulated in RCC tissues （P〈0.05） and RCC cell lines （P〈0.05）. The viabilities of 786-0 cells were decreased significantly after transfection with GV144-MEG3 for over 24 h （P〈0.05）. Consistently, the apoptosis rate was significantly increased in 786-0 cells transfected with GV144-MEG3 for 48 h （P〈0.05）. Furthermore, overexpression of MEG3 could reduce the expression of Bcl-2 and procaspase-9 proteins, enhance the expression of cleaved caspase-9 protein, and promote the release of cytochrome c protein to cytoplasm （P〈0.05）. Additionally, Bcl-2 mRNA level was declined by MEG3 overexpression （P〈0.05）. It was concluded that MEG3 induces the apoptosis of RCC cells possibly by activating the mitochondrial pathway.
文摘Background:We have shown that downregulation of materally expressed gene 3(MEG3)promoted autophagy and epithelial-mesenchymal transition to promote neuroblastoma(NB)progression.In present study,we aim to further discover the role of MEG3 in NB.Methods:Expression levels of MEG3 in stabled transfected cells were detected by qPCR.Flow cytometry was used to examine the effects of MEG3 overexpression on apoptosis and cell cycle.Moreover,tumor stemness was detected by tumor sphere formation assay.Results:QPCR showed that MEG3 was successfully overexpressed in SK-N-BE(2)C and SK-N-AS cells.CCK8 indicated MEG3 reduced cell proliferation in two NB cells.Flow cytometry revealed that MEG3 promoted apoptosis and caused G0/G1 arrest.Using chromatin isolation by RNA purification(ChIRP)and tumor sphere formation assays,we revealed that upregulation of MEG3 decreased tumor stemness by decreasing Nestin transcription.Conclusions:Overall,present study confirmed an anti-cancer role of MEG3 in NB,demonstrated that MEG3 could be a potential therapeutic target of NB.
文摘Long non-coding RNAs (lncRNAs) are transcripts longer than 200 nucleotides mostly transcribed by RNA which do not encode proteins. Previously, lncRNAs were considered transcriptional byproducts called “junk DNA” with no biological functions. There are many studies conducted on lncRNAs showing they are actively involved in regulation of epigenetic, transcriptional, and post-transcriptional events. Expressions of lncRNAs are more different in many malignant tumors than in benign tumors and normal tissue. Aberration of lncRNAs is responsible to promote or suppress tumorigenesis and cancer progression. Under different circumstances, lncRNAs exhibit their roles in carcinogenesis such as MALAT1 is responsible for intervening mRNA instability, HOTAIR, MALAT1, ANRIL, PVT1 links with miRNA and histonemodifying complexes, MEG3 associates with miRNA, CCAT2, MEG3, GAS5, UCA1 allies with c-Myc or P53 causing suppression of tumor or oncogenesis. Abnormal expressions of lncRNAs are noticed in gynecological cancers, such as cervical cancer, ovarian cancer, and endometrial cancer. Identification of cervical cancer associated lncRNAs is necessary to understand the molecular biogenesis of cancers. In this review, we summarized the foundation and function of the lncRNAs in terms of tumor progression, invasion, prognosis, apoptosis, metastasis, and chemo-resistance. This review will provide references to determine the clinical applications of lncRNAs as ideal diagnostic biomarkers or therapeutic targets in cervical cancers.
基金supported by the National Natural Science Foundation of China(No.81702132)the Zhejiang Provincial Natural Science Foundation of China(No.LY21H060007)+1 种基金the Projects of Medical and Health Technology Program in Zhejiang Province(No.2021KY206)the Wenzhou Public Welfare Scienceand Technology Research Project(Nos.Y20190267 and Y20210436),China.
文摘Objective:This research was performed to explore the effect of macrophage migration inhibitory factor(MIF)on the apoptosis of bone marrow mesenchymal stem cells(BMSCs)in ischemia and hypoxia environments.Methods:The cell viability of BMSCs incubated under hypoxia/ischemia(H/I)conditions with or without pretreatment with MIF or triglycidyl isocyanurate(TGIC)was detected using cell counting kit-8(CCK-8)analysis.Plasmids containing long noncoding RNA(lncRNA)maternally expressed gene 3(MEG3)orβ-catenin small interfering RNA(siRNA)were used to overexpress or downregulate the corresponding gene,and the p53 signaling pathway was activated by pretreatment with TGIC.The influences of MIF,overexpression of lncRNA MEG3,activation of the p53 signaling pathway,and silencing ofβ-catenin on H/I-induced apoptosis of BMSCs were revealed by western blotting,flow cytometry,and terminal deoxynucleotidyl transferase(TdT)-mediated dUTP nick-end labeling(TUNEL)staining.Results:From the results of CCK-8 assay,western blotting,and flow cytometry,pretreatment with MIF significantly decreased the H/I-induced apoptosis of BMSCs.This effect was inhibited when lncRNA MEG3 was overexpressed by plasmids containing MEG3.The p53 signaling pathway was activated by TGIC,andβ-catenin was silenced by siRNA.From western blot results,the expression levels ofβ-catenin in the nucleus and phosphorylated p53(p-p53)were downregulated and upregulated,respectively,when the lncRNA MEG3 was overexpressed.Through flow cytometry,MIF was also shown to significantly alleviate the increased reactive oxygen species(ROS)level of BMSCs caused by H/I.Conclusions:In summary,we conclude that MIF protected BMSCs from H/I-induced apoptosis by downregulating the lncRNA MEG3/p53 signaling pathway,activating the Wnt/β-catenin signaling pathway,and decreasing ROS levels.
基金supported by the National Natural Science Foundation of China(81830086,81988101,81702748,and 81902835)China Postdoctoral Science Foundation(2020M670067)+1 种基金Beijing Municipal Commission of Health and Family Planning Project(PXM2018_026279_000005)Guangdong Basic and Applied Basic Research Foundation(2019B030302012).
文摘Background:Long non-codingRNAs(lncRNAs)have been found to be involved in the development of many cancers.In this study,we aimed to identify the molecular mechanisms of lncRNA BAALC antisense RNA 1(BAALC-AS1)in regulating the malignancy of esophageal squamous cell carcinoma(ESCC).Methods:The expression of BAALC-AS1 in cancer patients was analyzed using a tissue microarray.The protein and RNA levels of BAALC-AS1 were determined by Western blotting analysis and quantitative reverse transcription-PCR(RT-qPCR),respectively.The cell proliferation was determined by cell viability assays,bromodeoxyuridine incorporation,and flow cytometry.The relationships among BAALC-AS1,RasGAPSH3 domain-binding protein 2(G3BP2),and c-Myc were determined using RNA immunoprecipitation,RNA pull-down assays,and luciferase assays.Results:The expression of BAALC-AS1 was highly up-regulated and associated with malignant phenotypes in ESCC tissues and cell lines.In vivo and in vitro assays showed that BAALC-AS1 promoted ESCC cell proliferation,migration,and invasion.BAALC-AS1 directly interacted with G3BP2,and thereby inhibited the degradation of c-Myc RNA 3’-UTR by G3BP2,thus leading to the accumulation of c-Myc expression.Additionally,c-Myc acted as a transcription factor that can induce the expression of BAALC-AS1 by directly binding to its promoter region.Conclusions:BAALC-AS1/G3BP2/c-Myc feedback loop plays a critical role in the development of ESCC,which might provide a novel therapeutic target and facilitate the development of new therapeutic strategies for the treatment of ESCC.
