Long noncoding RNA and microRNA are regulatory noncoding RNAs that are implicated in Alzheimer's disease, but the role of long noncoding RNA-associated competitive endogenous RNA has not been fully elucidated. The...Long noncoding RNA and microRNA are regulatory noncoding RNAs that are implicated in Alzheimer's disease, but the role of long noncoding RNA-associated competitive endogenous RNA has not been fully elucidated. The long noncoding RNA growth arrest-specific 5(GAS5) is a member of the 5′-terminal oligopyrimidine gene family that may be involved in neurological disorders, but its role in Alzheimer's disease remains unclear. This study aimed to investigate the function of GAS5 and construct a GAS5-associated competitive endogenous RNA network comprising potential targets. RNA sequencing results showed that GAS5 was upregulated in five familial Alzheimer's disease(5×FAD) mice, APPswe/PSEN1dE9(APP/PS1) mice, Alzheimer's disease-related APPswe cells, and serum from patients with Alzheimer's disease. Functional experiments with targeted overexpression and silencing demonstrated that GAS5 played a role in cognitive dysfunction and multiple Alzheimer's disease-associated pathologies, including tau hyperphosphorylation, amyloid-beta accumulation, and neuronal apoptosis. Mechanistic studies indicated that GAS5 acted as an endogenous sponge by competing for microRNA-23b-3p(miR-23b-3p) binding to regulate its targets glycogen synthase kinase 3beta(GSK-3β) and phosphatase and tensin homologue deleted on chromosome 10(PTEN) expression in an Argonaute 2-induced RNA silencing complex(RISC)-dependent manner. GAS5 inhibited miR-23b-3p-mediated GSK-3β and PTEN cascades with a feedforward PTEN/protein kinase B(Akt)/GSK-3β linkage. Furthermore, recovery of GAS5/miR-23b-3p/GSK-3β/PTEN pathways relieved Alzheimer's disease-like symptoms in vivo, indicated by the amelioration of spatial cognition, neuronal degeneration, amyloid-beta load, and tau phosphorylation. Together, these findings suggest that GAS5 promotes Alzheimer's disease pathogenesis. This study establishes the functional convergence of the GAS5/miR-23b-3p/GSK-3β/PTEN pathway on multiple pathologies, suggesting a candidate therapeutic target in Alzheimer's disease.展开更多
BACKGROUND Gastric cancer(GC)is a malignant tumor originating from gastric mucosal epithelial cells that has high morbidity and mortality.microRNAs(miR)are important diagnostic markers and therapeutic targets in this ...BACKGROUND Gastric cancer(GC)is a malignant tumor originating from gastric mucosal epithelial cells that has high morbidity and mortality.microRNAs(miR)are important diagnostic markers and therapeutic targets in this disease.AIM To explore the mechanism of miR-125a-5p in the pathogenesis of GC.METHODS The expression levels of miR-125a-5p,SERPINE1 and DNMT1 in GC cells and tissues were detected by real-time polymerase chain reaction(PCR)and Western blotting.Methylation-specific PCR was used to detect the level of miR-125a-5p methylation.A cell counting kit 8 assay,scratch test,and a Transwell assay were performed to detect the proliferation,migration,and invasiveness of HGC27 cells,respectively.The expression of the epithelial mesenchymal transition(EMT)-related proteins E-cadherin,N-cadherin and vimentin in HGC27 cells was detected by Western blotting,while the expression of vimentin was detected by immunofluorescence.RESULTS This study revealed that miR-125a-5p was expressed at low levels in GC clinical samples and cells and that miR-125a-5p overexpression inhibited the proliferation,migration,invasiveness and EMT of GC cells.Mechanistically,miR-125a-5p can reduce GC cell proliferation,promote E-cadherin expression,inhibit N-cadherin and vimentin expression,and reduce the EMT of GC cells,thus constraining GC cells to a certain extent.Moreover,DNMT1 inhibited miR-125a-5p expression by increasing the methylation of the miR-125a-5p promoter,thereby promoting the expression of SERPINE1,which acts together with miR-125a-5p to exert antagonistic effects on GC.CONCLUSION Our study revealed that DNMT1 promoted SERPINE1 protein expression by inducing miR-125a-5p methylation,which led to the proliferation,migration and occurrence of EMT in GC cells.展开更多
基金supported by the National Natural Science Foundation of China,Nos. 82173806 and U1803281Chinese Academy of Medical Sciences (CAMS) Innovation Fund for Medical Science,Nos. 2021-I2M-1-030 and 2022-I2M-2-002Non-Profit Central Research Institute Fund of Chinese Academy of Medical Sciences,No. 2022-JKCS-08 (all to RL)。
文摘Long noncoding RNA and microRNA are regulatory noncoding RNAs that are implicated in Alzheimer's disease, but the role of long noncoding RNA-associated competitive endogenous RNA has not been fully elucidated. The long noncoding RNA growth arrest-specific 5(GAS5) is a member of the 5′-terminal oligopyrimidine gene family that may be involved in neurological disorders, but its role in Alzheimer's disease remains unclear. This study aimed to investigate the function of GAS5 and construct a GAS5-associated competitive endogenous RNA network comprising potential targets. RNA sequencing results showed that GAS5 was upregulated in five familial Alzheimer's disease(5×FAD) mice, APPswe/PSEN1dE9(APP/PS1) mice, Alzheimer's disease-related APPswe cells, and serum from patients with Alzheimer's disease. Functional experiments with targeted overexpression and silencing demonstrated that GAS5 played a role in cognitive dysfunction and multiple Alzheimer's disease-associated pathologies, including tau hyperphosphorylation, amyloid-beta accumulation, and neuronal apoptosis. Mechanistic studies indicated that GAS5 acted as an endogenous sponge by competing for microRNA-23b-3p(miR-23b-3p) binding to regulate its targets glycogen synthase kinase 3beta(GSK-3β) and phosphatase and tensin homologue deleted on chromosome 10(PTEN) expression in an Argonaute 2-induced RNA silencing complex(RISC)-dependent manner. GAS5 inhibited miR-23b-3p-mediated GSK-3β and PTEN cascades with a feedforward PTEN/protein kinase B(Akt)/GSK-3β linkage. Furthermore, recovery of GAS5/miR-23b-3p/GSK-3β/PTEN pathways relieved Alzheimer's disease-like symptoms in vivo, indicated by the amelioration of spatial cognition, neuronal degeneration, amyloid-beta load, and tau phosphorylation. Together, these findings suggest that GAS5 promotes Alzheimer's disease pathogenesis. This study establishes the functional convergence of the GAS5/miR-23b-3p/GSK-3β/PTEN pathway on multiple pathologies, suggesting a candidate therapeutic target in Alzheimer's disease.
基金the Research Program of the Science and Technology Department of Yunnan Province,No.202101AY070001-204.
文摘BACKGROUND Gastric cancer(GC)is a malignant tumor originating from gastric mucosal epithelial cells that has high morbidity and mortality.microRNAs(miR)are important diagnostic markers and therapeutic targets in this disease.AIM To explore the mechanism of miR-125a-5p in the pathogenesis of GC.METHODS The expression levels of miR-125a-5p,SERPINE1 and DNMT1 in GC cells and tissues were detected by real-time polymerase chain reaction(PCR)and Western blotting.Methylation-specific PCR was used to detect the level of miR-125a-5p methylation.A cell counting kit 8 assay,scratch test,and a Transwell assay were performed to detect the proliferation,migration,and invasiveness of HGC27 cells,respectively.The expression of the epithelial mesenchymal transition(EMT)-related proteins E-cadherin,N-cadherin and vimentin in HGC27 cells was detected by Western blotting,while the expression of vimentin was detected by immunofluorescence.RESULTS This study revealed that miR-125a-5p was expressed at low levels in GC clinical samples and cells and that miR-125a-5p overexpression inhibited the proliferation,migration,invasiveness and EMT of GC cells.Mechanistically,miR-125a-5p can reduce GC cell proliferation,promote E-cadherin expression,inhibit N-cadherin and vimentin expression,and reduce the EMT of GC cells,thus constraining GC cells to a certain extent.Moreover,DNMT1 inhibited miR-125a-5p expression by increasing the methylation of the miR-125a-5p promoter,thereby promoting the expression of SERPINE1,which acts together with miR-125a-5p to exert antagonistic effects on GC.CONCLUSION Our study revealed that DNMT1 promoted SERPINE1 protein expression by inducing miR-125a-5p methylation,which led to the proliferation,migration and occurrence of EMT in GC cells.