BACKGROUND Endoplasmic reticulum(ER)stress-related hepatocyte apoptosis is responsible for multiple hepatic diseases.Previous studies have revealed that endoplasmic reticulophagy(ER-phagy)promotes the selective cleara...BACKGROUND Endoplasmic reticulum(ER)stress-related hepatocyte apoptosis is responsible for multiple hepatic diseases.Previous studies have revealed that endoplasmic reticulophagy(ER-phagy)promotes the selective clearance of damaged ER fragments during ER stress,playing a crucial role in maintaining ER homeostasis and inhibiting apoptosis.Family with sequence similarity 134 member B(FAM134B)is a receptor involved in ER-phagy that can form a complex with calnexin(CNX)and microtubule-associated protein 1 light chain 3(LC3).The complex can mediate the selective isolation of ER fragments to attenuate hepatocyte apoptosis.However,the precise regulatory mechanisms remain unclear.AIM To elucidate the effect of FAM134B-mediated ER-phagy on ER stress-induced apoptosis in buffalo rat liver 3A(BRL-3A)rat hepatocytes and the potential regulatory mechanisms.METHODS ER stress-related hepatocyte apoptosis was induced using dithiothreitol(DTT).Proteins related to ER stress and autophagy were measured with western blotting.Protein complex interactions with FAM134B were isolated by co-immunoprecipitation.ER-phagy was evaluated in immunofluorescence experiments.Cell cycle distribution and apoptosis were measured by flow cytometry.Mitochondrial Ca^(2+) levels were evaluated by the co-localization of intracellular Ca^(2+)-tracker and Mitotracker.The small interfering RNA against FAM134B was used to knockdown FAM134B in BRL-3A cells.RESULTS ER stress-related and autophagy-related proteins in BRL-3A cells were elevated by both short and long-term DTT treatment.Furthermore,co-immunoprecipitation confirmed an interaction between FAM134B,CNX,FAM134B,and LC3 in BRL-3A cells.Immunofluorescence assays revealed that autolysosomes significantly decreased following short-term DTT treatment,but increased after long-term treatment.Mitochondrial Ca2+levels and apoptotic rates were dramatically elevated,and more cells were arrested in the G1 stage after short-term DTT treatment;however,these decreased 48 h later.Moreover,FAM134B downregulation accelerated mitochondrial apoptotic pathway activation and aggravated hepatocyte apoptosis under ER stress.CONCLUSION FAM134B-mediated ER-phagy attenuates hepatocyte apoptosis by suppressing the mitochondrial apoptotic pathway.Our findings provide new evidence highlighting the importance of FAM134Bmediated ER-phagy in attenuating hepatocyte apoptosis.展开更多
目的探究序列相似家族111成员A(family with sequence similarity 111 member A,FAM111A)、FAM111B在泛癌中的肿瘤预后、肿瘤免疫及抗癌药物敏感性。方法在癌症基因体图谱(the cancer genome atlas,TCGA)数据库下载和整理FAM111A和FAM1...目的探究序列相似家族111成员A(family with sequence similarity 111 member A,FAM111A)、FAM111B在泛癌中的肿瘤预后、肿瘤免疫及抗癌药物敏感性。方法在癌症基因体图谱(the cancer genome atlas,TCGA)数据库下载和整理FAM111A和FAM111B在33种肿瘤及11057例样本的mRNA表达水平及临床生存相关数据,下载UCSC Xena数据库中关于33种肿瘤干细胞评分相关数据,下载CellMiner数据库样本的基因表达与药敏结果的数据。对FAM111A与FAM111B在肿瘤中作用进行多方面研究。结果FAM111A和FAM111B的相关性较强(r=0.42,P<0.05),FAM111A和FAM111B在多种肿瘤中普遍高表达(P<0.05),且FAM111A和FAM111B可以预测多种肿瘤患者的生存率(P<0.05)。泛癌免疫亚型分析显示,FAM111A和FAM111B在6种肿瘤免疫亚型显著表达(P<0.001)。FAM111A和FAM111B的表达与免疫评分、间质评分及总评分呈负相关(P<0.05),FAM111A和FAM111B的表达与肿瘤干细胞分化程度呈正相关(P<0.05)。抗癌药物敏感性的分析显示,FAM111A与奈拉滨(Nelarabine)等药物敏感性呈正相关(P<0.05),FAM111基因与卡博替尼(Cabozantinib)等药物敏感性呈负相关(P<0.05)。结论FAM111A和FAM111B在多种肿瘤中有表达差异,并且对生存预后有预测价值,它们在肿瘤免疫微环境、干细胞评分和抗癌药物敏感性方面的研究结果为肿瘤治疗及诊断提供了方向。展开更多
基金Supported by National Natural Science Foundation of China,No.81560105Science and Technology Foundation of Guizhou Province,No.Qiankehe Jichu-ZK[2021]365,and No.Qiankehe Pingtai Rencai[2019]5801National Natural Science Foundation Cultivation Project of Guizhou Medical University,No.20NSP016。
文摘BACKGROUND Endoplasmic reticulum(ER)stress-related hepatocyte apoptosis is responsible for multiple hepatic diseases.Previous studies have revealed that endoplasmic reticulophagy(ER-phagy)promotes the selective clearance of damaged ER fragments during ER stress,playing a crucial role in maintaining ER homeostasis and inhibiting apoptosis.Family with sequence similarity 134 member B(FAM134B)is a receptor involved in ER-phagy that can form a complex with calnexin(CNX)and microtubule-associated protein 1 light chain 3(LC3).The complex can mediate the selective isolation of ER fragments to attenuate hepatocyte apoptosis.However,the precise regulatory mechanisms remain unclear.AIM To elucidate the effect of FAM134B-mediated ER-phagy on ER stress-induced apoptosis in buffalo rat liver 3A(BRL-3A)rat hepatocytes and the potential regulatory mechanisms.METHODS ER stress-related hepatocyte apoptosis was induced using dithiothreitol(DTT).Proteins related to ER stress and autophagy were measured with western blotting.Protein complex interactions with FAM134B were isolated by co-immunoprecipitation.ER-phagy was evaluated in immunofluorescence experiments.Cell cycle distribution and apoptosis were measured by flow cytometry.Mitochondrial Ca^(2+) levels were evaluated by the co-localization of intracellular Ca^(2+)-tracker and Mitotracker.The small interfering RNA against FAM134B was used to knockdown FAM134B in BRL-3A cells.RESULTS ER stress-related and autophagy-related proteins in BRL-3A cells were elevated by both short and long-term DTT treatment.Furthermore,co-immunoprecipitation confirmed an interaction between FAM134B,CNX,FAM134B,and LC3 in BRL-3A cells.Immunofluorescence assays revealed that autolysosomes significantly decreased following short-term DTT treatment,but increased after long-term treatment.Mitochondrial Ca2+levels and apoptotic rates were dramatically elevated,and more cells were arrested in the G1 stage after short-term DTT treatment;however,these decreased 48 h later.Moreover,FAM134B downregulation accelerated mitochondrial apoptotic pathway activation and aggravated hepatocyte apoptosis under ER stress.CONCLUSION FAM134B-mediated ER-phagy attenuates hepatocyte apoptosis by suppressing the mitochondrial apoptotic pathway.Our findings provide new evidence highlighting the importance of FAM134Bmediated ER-phagy in attenuating hepatocyte apoptosis.
文摘目的探究序列相似家族111成员A(family with sequence similarity 111 member A,FAM111A)、FAM111B在泛癌中的肿瘤预后、肿瘤免疫及抗癌药物敏感性。方法在癌症基因体图谱(the cancer genome atlas,TCGA)数据库下载和整理FAM111A和FAM111B在33种肿瘤及11057例样本的mRNA表达水平及临床生存相关数据,下载UCSC Xena数据库中关于33种肿瘤干细胞评分相关数据,下载CellMiner数据库样本的基因表达与药敏结果的数据。对FAM111A与FAM111B在肿瘤中作用进行多方面研究。结果FAM111A和FAM111B的相关性较强(r=0.42,P<0.05),FAM111A和FAM111B在多种肿瘤中普遍高表达(P<0.05),且FAM111A和FAM111B可以预测多种肿瘤患者的生存率(P<0.05)。泛癌免疫亚型分析显示,FAM111A和FAM111B在6种肿瘤免疫亚型显著表达(P<0.001)。FAM111A和FAM111B的表达与免疫评分、间质评分及总评分呈负相关(P<0.05),FAM111A和FAM111B的表达与肿瘤干细胞分化程度呈正相关(P<0.05)。抗癌药物敏感性的分析显示,FAM111A与奈拉滨(Nelarabine)等药物敏感性呈正相关(P<0.05),FAM111基因与卡博替尼(Cabozantinib)等药物敏感性呈负相关(P<0.05)。结论FAM111A和FAM111B在多种肿瘤中有表达差异,并且对生存预后有预测价值,它们在肿瘤免疫微环境、干细胞评分和抗癌药物敏感性方面的研究结果为肿瘤治疗及诊断提供了方向。
