BACKGROUND Prohibitin 1(PHB1)has been identified as an antiproliferative protein that is highly conserved and ubiquitously expressed,and it participates in a variety of essential cellular functions,including apoptosis...BACKGROUND Prohibitin 1(PHB1)has been identified as an antiproliferative protein that is highly conserved and ubiquitously expressed,and it participates in a variety of essential cellular functions,including apoptosis,cell cycle regulation,prolifera-tion,and survival.Emerging evidence indicates that PHB1 may play an important role in the progression of hepatocellular carcinoma(HCC).However,the role of PHB1 in HCC is controversial.AIM To investigate the effects of PHB1 on the proliferation and apoptosis of human HCC cells and the relevant mechanisms in vitro.METHODS HCC patients and healthy individuals were enrolled in this study according to the inclusion and exclusion criteria;then,PHB1 levels in the sera and liver tissues of these participates were determined using ELISA,RT-PCR,and immunohistoche-mistry.Human HepG2 and SMMC-7721 cells were transfected with the pEGFP-PHB1 plasmid and PHB1-specific shRNA(shRNA-PHB1)for 24-72 h.Cell prolif-eration was analysed with an MTT assay.Cell cycle progression and apoptosis were analysed using flow cytometry(FACS).The mRNA and protein expression levels of the cell cycle-related molecules p21,Cyclin A2,Cyclin E1,and CDK2 and the cell apoptosis-related molecules cytochrome C(Cyt C),p53,Bcl-2,Bax,caspase 3,and caspase 9 were measured by real-time PCR and Western blot,respectively.RESULTS Decreased levels of PHB1 were found in the sera and liver tissues of HCC patients compared to those of healthy individuals,and decreased PHB1 was positively correlated with low differentiation,TNM stage III-IV,and alpha-fetoprotein≥400μg/L.Overexpression of PHB1 significantly inhibited human HCC cell proliferation in a time-dependent manner.FACS revealed that the overexpression of PHB1 arrested HCC cells in the G0/G1 phase of the cell cycle and induced apoptosis.The proportion of cells in the G0/G1 phase was significantly increased and the proportion of cells in the S phase was decreased in HepG2 cells that were transfected with pEGFP-PHB1 compared with untreated control and empty vector-transfected cells.The percentage of apoptotic HepG2 cells that were transfected with pEGFP-PHB1 was 15.41%±1.06%,which was significantly greater than that of apoptotic control cells(3.65%±0.85%,P<0.01)and empty vector-transfected cells(4.21%±0.52%,P<0.01).Similar results were obtained with SMMC-7721 cells.Furthermore,the mRNA and protein expression levels of p53,p21,Bax,caspase 3,and caspase 9 were increased while the mRNA and protein expression levels of Cyclin A2,Cy-clin E1,CDK2,and Bcl-2 were decreased when PHB1 was overexpressed in human HCC cells.However,when PHB1 was upregulated in human HCC cells,Cyt C expression levels were increased in the cytosol and decreased in the mitochondria,which indicated that Cyt C had been released into the cytosol.Conversely,these effects were reversed when PHB1 was knocked down.CONCLUSION PHB1 inhibits human HCC cell viability by arresting the cell cycle and inducing cell apoptosis via activation of the p53-mediated mitochondrial pathway.展开更多
BACKGROUND The function of prohibitin 1(Phb1)during liver regeneration(LR)remains relatively unexplored.Our previous research identified downregulation of Phb1 in rat liver mitochondria 24 h after 70%partial hepatecto...BACKGROUND The function of prohibitin 1(Phb1)during liver regeneration(LR)remains relatively unexplored.Our previous research identified downregulation of Phb1 in rat liver mitochondria 24 h after 70%partial hepatectomy(PHx),as determined by subcellular proteomic analysis.AIM To investigate the potential role of Phb1 during LR.METHODS We examined changes in Phb1 mRNA and protein levels,subcellular distribution,and abundance in rat liver during LR following 70%PHx.We also evaluated mitochondrial changes and apoptosis using electron microscopy and flow cytometry.RNA-interference-mediated knockdown of Phb1(PHBi)was performed in BRL-3A cells.RESULTS Compared with sham-operation control groups,Phb1 mRNA and protein levels in 70%PHx test groups were downregulated at 24 h,then upregulated at 72 and 168 h.Phb1 was mainly located in mitochondria,showed a reduced abundance at 24 h,significantly increased at 72 h,and almost recovered to normal at 168 h.Phb1 was also present in nuclei,with continuous increase in abundance observed 72 and 168 h after 70%PHx.The altered ultrastructure and reduced mass of mitochondria during LR had almost completely recovered to normal at 168 h.PHBi in BRL-3A cells resulted in increased S-phase entry,a higher number of apoptotic cells,and disruption of mitochondrial membrane potential.CONCLUSION Phb1 may contribute to maintaining mitochondrial stability and could play a role in regulating cell proliferation and apoptosis of rat liver cells during LR.展开更多
目的对比Prohibitin(PMB)在不同家族史的鼻咽癌患者癌组织中的表达,以探究鼻咽组织中Prohibitin是否可以作为鼻咽癌潜在标记物。方法收集高癌家系气虚质鼻咽癌患者、鼻咽黏膜慢性炎症患者的鼻咽组织各9例,散发气虚质鼻咽癌患者的鼻咽组...目的对比Prohibitin(PMB)在不同家族史的鼻咽癌患者癌组织中的表达,以探究鼻咽组织中Prohibitin是否可以作为鼻咽癌潜在标记物。方法收集高癌家系气虚质鼻咽癌患者、鼻咽黏膜慢性炎症患者的鼻咽组织各9例,散发气虚质鼻咽癌患者的鼻咽组织12例,应用实时定量PCR方法检测Prohibitin在各组鼻咽组织中的表达。利用Western-blotting蛋白免疫印迹方法检测Prohibitin在各组患者鼻咽组织中的表达。结果 PHB m RNA在鼻咽黏膜慢性炎症鼻咽组织、散发气虚质鼻咽癌组织、高癌家系气虚质鼻咽癌组织中的2-△△Ct值分别为1.00±0.72、1.08±0.49、0.97±0.41(P>0.05)。PHB蛋白相对表达依次为0.33±0.21、0.59±0.25、1.72±0.96(P<0.05)。分析各组间对比PHB基因表达量无明显变化,但蛋白表达量鼻咽癌患者明显高于正常人,高癌家系鼻咽癌患者蛋白表达量高于散发患者,考虑与级联放大反应有关,有望成为高癌家系气虚质鼻咽癌患者早期诊断及筛查的标志物。展开更多
基金the Key Research and Development Program of Shaanxi,No.2021SF-227 and No.2020SF-297the Natural Science Basic Research Program of Shaanxi,No.2023-JC-YB-770。
文摘BACKGROUND Prohibitin 1(PHB1)has been identified as an antiproliferative protein that is highly conserved and ubiquitously expressed,and it participates in a variety of essential cellular functions,including apoptosis,cell cycle regulation,prolifera-tion,and survival.Emerging evidence indicates that PHB1 may play an important role in the progression of hepatocellular carcinoma(HCC).However,the role of PHB1 in HCC is controversial.AIM To investigate the effects of PHB1 on the proliferation and apoptosis of human HCC cells and the relevant mechanisms in vitro.METHODS HCC patients and healthy individuals were enrolled in this study according to the inclusion and exclusion criteria;then,PHB1 levels in the sera and liver tissues of these participates were determined using ELISA,RT-PCR,and immunohistoche-mistry.Human HepG2 and SMMC-7721 cells were transfected with the pEGFP-PHB1 plasmid and PHB1-specific shRNA(shRNA-PHB1)for 24-72 h.Cell prolif-eration was analysed with an MTT assay.Cell cycle progression and apoptosis were analysed using flow cytometry(FACS).The mRNA and protein expression levels of the cell cycle-related molecules p21,Cyclin A2,Cyclin E1,and CDK2 and the cell apoptosis-related molecules cytochrome C(Cyt C),p53,Bcl-2,Bax,caspase 3,and caspase 9 were measured by real-time PCR and Western blot,respectively.RESULTS Decreased levels of PHB1 were found in the sera and liver tissues of HCC patients compared to those of healthy individuals,and decreased PHB1 was positively correlated with low differentiation,TNM stage III-IV,and alpha-fetoprotein≥400μg/L.Overexpression of PHB1 significantly inhibited human HCC cell proliferation in a time-dependent manner.FACS revealed that the overexpression of PHB1 arrested HCC cells in the G0/G1 phase of the cell cycle and induced apoptosis.The proportion of cells in the G0/G1 phase was significantly increased and the proportion of cells in the S phase was decreased in HepG2 cells that were transfected with pEGFP-PHB1 compared with untreated control and empty vector-transfected cells.The percentage of apoptotic HepG2 cells that were transfected with pEGFP-PHB1 was 15.41%±1.06%,which was significantly greater than that of apoptotic control cells(3.65%±0.85%,P<0.01)and empty vector-transfected cells(4.21%±0.52%,P<0.01).Similar results were obtained with SMMC-7721 cells.Furthermore,the mRNA and protein expression levels of p53,p21,Bax,caspase 3,and caspase 9 were increased while the mRNA and protein expression levels of Cyclin A2,Cy-clin E1,CDK2,and Bcl-2 were decreased when PHB1 was overexpressed in human HCC cells.However,when PHB1 was upregulated in human HCC cells,Cyt C expression levels were increased in the cytosol and decreased in the mitochondria,which indicated that Cyt C had been released into the cytosol.Conversely,these effects were reversed when PHB1 was knocked down.CONCLUSION PHB1 inhibits human HCC cell viability by arresting the cell cycle and inducing cell apoptosis via activation of the p53-mediated mitochondrial pathway.
文摘BACKGROUND The function of prohibitin 1(Phb1)during liver regeneration(LR)remains relatively unexplored.Our previous research identified downregulation of Phb1 in rat liver mitochondria 24 h after 70%partial hepatectomy(PHx),as determined by subcellular proteomic analysis.AIM To investigate the potential role of Phb1 during LR.METHODS We examined changes in Phb1 mRNA and protein levels,subcellular distribution,and abundance in rat liver during LR following 70%PHx.We also evaluated mitochondrial changes and apoptosis using electron microscopy and flow cytometry.RNA-interference-mediated knockdown of Phb1(PHBi)was performed in BRL-3A cells.RESULTS Compared with sham-operation control groups,Phb1 mRNA and protein levels in 70%PHx test groups were downregulated at 24 h,then upregulated at 72 and 168 h.Phb1 was mainly located in mitochondria,showed a reduced abundance at 24 h,significantly increased at 72 h,and almost recovered to normal at 168 h.Phb1 was also present in nuclei,with continuous increase in abundance observed 72 and 168 h after 70%PHx.The altered ultrastructure and reduced mass of mitochondria during LR had almost completely recovered to normal at 168 h.PHBi in BRL-3A cells resulted in increased S-phase entry,a higher number of apoptotic cells,and disruption of mitochondrial membrane potential.CONCLUSION Phb1 may contribute to maintaining mitochondrial stability and could play a role in regulating cell proliferation and apoptosis of rat liver cells during LR.
文摘目的对比Prohibitin(PMB)在不同家族史的鼻咽癌患者癌组织中的表达,以探究鼻咽组织中Prohibitin是否可以作为鼻咽癌潜在标记物。方法收集高癌家系气虚质鼻咽癌患者、鼻咽黏膜慢性炎症患者的鼻咽组织各9例,散发气虚质鼻咽癌患者的鼻咽组织12例,应用实时定量PCR方法检测Prohibitin在各组鼻咽组织中的表达。利用Western-blotting蛋白免疫印迹方法检测Prohibitin在各组患者鼻咽组织中的表达。结果 PHB m RNA在鼻咽黏膜慢性炎症鼻咽组织、散发气虚质鼻咽癌组织、高癌家系气虚质鼻咽癌组织中的2-△△Ct值分别为1.00±0.72、1.08±0.49、0.97±0.41(P>0.05)。PHB蛋白相对表达依次为0.33±0.21、0.59±0.25、1.72±0.96(P<0.05)。分析各组间对比PHB基因表达量无明显变化,但蛋白表达量鼻咽癌患者明显高于正常人,高癌家系鼻咽癌患者蛋白表达量高于散发患者,考虑与级联放大反应有关,有望成为高癌家系气虚质鼻咽癌患者早期诊断及筛查的标志物。
