目的探究RNA结合蛋白(RNA-binding protein,RBP)Ras-GTP酶激活蛋白SH3结构域结合蛋白1(Ras-GTPase-activating protein SH3 domain-binding protein 1,G3BP1)在肺腺癌细胞免疫杀伤过程中的作用及其分子机制。方法运用在线数据库癌症基...目的探究RNA结合蛋白(RNA-binding protein,RBP)Ras-GTP酶激活蛋白SH3结构域结合蛋白1(Ras-GTPase-activating protein SH3 domain-binding protein 1,G3BP1)在肺腺癌细胞免疫杀伤过程中的作用及其分子机制。方法运用在线数据库癌症基因组图谱(The Cancer Genome Atlas,TCGA)分析肺腺癌样本中G3BP1与程序性死亡受体配体1(programmed death-ligand 1,PD-L1)的相关性。采用慢病毒转染构建G3BP1过表达的肺腺癌A549细胞和G3BP1敲低的肺腺癌H1975细胞模型。采用逆转录聚合酶链反应(reverse transcription polymerase chain reaction,RT-PCR)和蛋白质印迹法检测细胞中mRNA和蛋白表达水平。采用T细胞杀伤实验评估细胞毒性T淋巴细胞(cytotoxic T lymphocyte,CTL)对细胞的免疫杀伤能力。采用免疫荧光-荧光原位杂交实验、RNA免疫共沉淀实验和RNA稳定性实验探究G3BP1对PD-L1 mRNA的调控机制。利用Kaplan-Meier plotter数据库分析G3BP1和PD-L1表达水平对肺腺癌患者预后的影响。结果TCGA数据库分析显示,526例肺腺癌样本中G3BP1与PD-L1的表达呈正相关(r=0.326,P<0.01)。G3BP1过表达可促进A549细胞PD-L1的mRNA和蛋白表达(均P<0.05),进而抑制CTL对肺腺癌细胞的免疫杀伤作用(P<0.01)。敲低G3BP1能抑制H1975细胞PD-L1 mRNA和蛋白表达(均P<0.05),增强CTL的免疫杀伤效果(P<0.01)。在A549和H1975细胞中G3BP1可通过与PD-L1 mRNA结合,提高其稳定性,从而促进蛋白表达。Kaplan-Meier plotter数据库分析显示,G3BP1和PD-L1高表达的肺腺癌患者总生存期和初次进展期均较相应低表达患者缩短(均P<0.01)。结论G3BP1通过稳定PD-L1 mRNA抑制肺腺癌细胞的免疫杀伤过程,且其高表达与患者不良预后相关。展开更多
Recently,a novel research led by Mallika Singh and Kenneth P.Olive^(1,2) published in Nature identified a highly selective inhibitor(RMC-7977)of the active GTP-bound forms of human RAS family(KRAS,HRAS and NRAS)with a...Recently,a novel research led by Mallika Singh and Kenneth P.Olive^(1,2) published in Nature identified a highly selective inhibitor(RMC-7977)of the active GTP-bound forms of human RAS family(KRAS,HRAS and NRAS)with affinity for both mutant and wild-type variants.Moreover,they assessed the therapeutic potential of RMC-7977 in a comprehensive range of human pancreatic ductal adenocarcinoma(PDAC)models and proved that RMC-7977 could induce apoptosis and sustained proliferative arrest,whereas normal tissues underwent only transient decreases in proliferation.Meanwhile.展开更多
文摘Recently,a novel research led by Mallika Singh and Kenneth P.Olive^(1,2) published in Nature identified a highly selective inhibitor(RMC-7977)of the active GTP-bound forms of human RAS family(KRAS,HRAS and NRAS)with affinity for both mutant and wild-type variants.Moreover,they assessed the therapeutic potential of RMC-7977 in a comprehensive range of human pancreatic ductal adenocarcinoma(PDAC)models and proved that RMC-7977 could induce apoptosis and sustained proliferative arrest,whereas normal tissues underwent only transient decreases in proliferation.Meanwhile.
