Objective:Gastric cancer(GC)is a globally common cancer characterized by high incidence and mortality worldwide.Advances in the molecular understanding of GC provide promising targets for GC diagnosis and therapy.Long...Objective:Gastric cancer(GC)is a globally common cancer characterized by high incidence and mortality worldwide.Advances in the molecular understanding of GC provide promising targets for GC diagnosis and therapy.Long non-coding RNAs(lncRNAs)and their downstream regulators are regarded to be implicated in the progression of multiple types of malignancies.Studies have shown that the lncRNA small nucleolar RNA host gene 4(SNHG4)serves as a tumor promoter in various malignancies,while its function in GC has yet to be characterized.Therefore,our study aimed to explore the role and underlying mechanism of SNHG4 in GC.Methods:We used qRT-PCR to analyze SNHG4 expression in GC tissues and cells.Kaplan-Meier analysis was used to assess the correlation between SNHG4 expression and the survival rate of GC patients.Cellular function experiments such as CCK-8,BrdU,colony formation,flow cytometry analysis,and transwell were performed to explore the effects of SNHG4 on GC cell proliferation,apoptosis,cell cycle,migration,and invasion.We also established xenograft mouse models to explore the effect of SNHG4 on GC tumor growth.Mechanically,dual luciferase reporter assay was used to verify the interaction between SNHG4 and miR-409-3p and between miR-409-3p and cAMP responsive element binding protein 1(CREB1).Results:The results indicated that SNHG4 was overexpressed in GC tissues and cell lines,and was linked with poor survival rate of GC patients.SNHG4 promoted GC cell proliferation,migration,and invasion while inhibiting cell apoptosis and cell cycle arrest in vitro.The in vivo experiment indicated that SNHG4 facilitated GC tumor growth.Furthermore,SNHG4 was demonstrated to bind to miR-409-3p.Moreover,CREB1 was directly targeted by miR-409-3p.Rescue assays demonstrated that miR-409-3p deficiency reversed the suppressive impact of SNHG4 knockdown on GC cell malignancy.Additionally,miR-409-3p was also revealed to inhibit GC cell proliferation,migration,and invasion by targeting CREB1.Conclusion:In conclusion,we verified that the SNHG4 promoted GC growth and metastasis by binding to miR-409-3p to upregulate CREB1,which may deepen the understanding of the underlying mechanism in GC development.展开更多
BACKGROUND Diabetic retinopathy(DR)is one of the major eye diseases contributing to blindness worldwide.Endoplasmic reticulum(ER)stress in retinal cells is a key factor leading to retinal inflammation and vascular lea...BACKGROUND Diabetic retinopathy(DR)is one of the major eye diseases contributing to blindness worldwide.Endoplasmic reticulum(ER)stress in retinal cells is a key factor leading to retinal inflammation and vascular leakage in DR,but its mechanism is still unclear.AIM To investigate the potential mechanism of LEF1 and related RNAs in DR.METHODS ARPE-19 cells were exposed to high levels of glucose for 24 hours to simulate a diabetic environment.Intraperitoneally injected streptozotocin was used to induce the rat model of DR.The expression levels of genes and related proteins were measured by RT-qPCR and Western blotting;lnc-MGC and miR-495-3p were detected by fluorescent in situ hybridization;CCK-8 and TUNEL assays were used to detect cell viability and apoptosis;enzyme-linked immunosorbent assay was used to detect inflammatory factors;dual-luciferase gene assays were used to verify the targeting relationship;and the retina was observed by HE staining.RESULTS LEF1 and lnc-MGC have binding sites,and lnc-MGC can regulate the miR-495-3p/GRP78 molecular axis.In high glucose-treated cells,inflammation was aggravated,the intracellular reactive oxygen species concentration was increased,cell viability was reduced,apoptosis was increased,the ER response was intensified,and ferroptosis was increased.As an ER molecular chaperone,GRP78 regulates the ER and ferroptosis under the targeting of miR-495-3p,whereas inhibiting LEF1 can further downregulate the expression of lnc-MGC,increase the level of miR-495-3p,and sequentially regulate the level of GRP78 to alleviate the occurrence and development of DR.Animal experiments indicated that the knockdown of LEF1 can affect the lnc-MGC/miR-495-3p/GRP78 signaling axis to restrain the progression of DR.CONCLUSION LEF1 knockdown can regulate the miR-495-3p/GRP78 molecular axis through lnc-MGC,which affects ER stress and restrains the progression of DR and ferroptosis in retinal pigment epithelial cells.展开更多
文摘Objective:Gastric cancer(GC)is a globally common cancer characterized by high incidence and mortality worldwide.Advances in the molecular understanding of GC provide promising targets for GC diagnosis and therapy.Long non-coding RNAs(lncRNAs)and their downstream regulators are regarded to be implicated in the progression of multiple types of malignancies.Studies have shown that the lncRNA small nucleolar RNA host gene 4(SNHG4)serves as a tumor promoter in various malignancies,while its function in GC has yet to be characterized.Therefore,our study aimed to explore the role and underlying mechanism of SNHG4 in GC.Methods:We used qRT-PCR to analyze SNHG4 expression in GC tissues and cells.Kaplan-Meier analysis was used to assess the correlation between SNHG4 expression and the survival rate of GC patients.Cellular function experiments such as CCK-8,BrdU,colony formation,flow cytometry analysis,and transwell were performed to explore the effects of SNHG4 on GC cell proliferation,apoptosis,cell cycle,migration,and invasion.We also established xenograft mouse models to explore the effect of SNHG4 on GC tumor growth.Mechanically,dual luciferase reporter assay was used to verify the interaction between SNHG4 and miR-409-3p and between miR-409-3p and cAMP responsive element binding protein 1(CREB1).Results:The results indicated that SNHG4 was overexpressed in GC tissues and cell lines,and was linked with poor survival rate of GC patients.SNHG4 promoted GC cell proliferation,migration,and invasion while inhibiting cell apoptosis and cell cycle arrest in vitro.The in vivo experiment indicated that SNHG4 facilitated GC tumor growth.Furthermore,SNHG4 was demonstrated to bind to miR-409-3p.Moreover,CREB1 was directly targeted by miR-409-3p.Rescue assays demonstrated that miR-409-3p deficiency reversed the suppressive impact of SNHG4 knockdown on GC cell malignancy.Additionally,miR-409-3p was also revealed to inhibit GC cell proliferation,migration,and invasion by targeting CREB1.Conclusion:In conclusion,we verified that the SNHG4 promoted GC growth and metastasis by binding to miR-409-3p to upregulate CREB1,which may deepen the understanding of the underlying mechanism in GC development.
基金Supported by Science and Technology Program of Yunnan Provincial Department of Science and Technology-Basic Research Program,No.202301BA070001-025.
文摘BACKGROUND Diabetic retinopathy(DR)is one of the major eye diseases contributing to blindness worldwide.Endoplasmic reticulum(ER)stress in retinal cells is a key factor leading to retinal inflammation and vascular leakage in DR,but its mechanism is still unclear.AIM To investigate the potential mechanism of LEF1 and related RNAs in DR.METHODS ARPE-19 cells were exposed to high levels of glucose for 24 hours to simulate a diabetic environment.Intraperitoneally injected streptozotocin was used to induce the rat model of DR.The expression levels of genes and related proteins were measured by RT-qPCR and Western blotting;lnc-MGC and miR-495-3p were detected by fluorescent in situ hybridization;CCK-8 and TUNEL assays were used to detect cell viability and apoptosis;enzyme-linked immunosorbent assay was used to detect inflammatory factors;dual-luciferase gene assays were used to verify the targeting relationship;and the retina was observed by HE staining.RESULTS LEF1 and lnc-MGC have binding sites,and lnc-MGC can regulate the miR-495-3p/GRP78 molecular axis.In high glucose-treated cells,inflammation was aggravated,the intracellular reactive oxygen species concentration was increased,cell viability was reduced,apoptosis was increased,the ER response was intensified,and ferroptosis was increased.As an ER molecular chaperone,GRP78 regulates the ER and ferroptosis under the targeting of miR-495-3p,whereas inhibiting LEF1 can further downregulate the expression of lnc-MGC,increase the level of miR-495-3p,and sequentially regulate the level of GRP78 to alleviate the occurrence and development of DR.Animal experiments indicated that the knockdown of LEF1 can affect the lnc-MGC/miR-495-3p/GRP78 signaling axis to restrain the progression of DR.CONCLUSION LEF1 knockdown can regulate the miR-495-3p/GRP78 molecular axis through lnc-MGC,which affects ER stress and restrains the progression of DR and ferroptosis in retinal pigment epithelial cells.
