摘要
目的:检测卵巢肿瘤(ovarian tumor,OTU)结构域线性链接特异性去泛素化酶(OTU domain deubiquitinase with linear linkage specificity,OTULIN)在胃癌组织中的表达情况,并探讨敲除OTULIN基因表达对胃癌MKN45和AGS细胞增殖的影响,及可能的作用机制。方法:采用免疫组织化学法检测73例胃癌组织与24例正常胃黏膜组织中OTULIN的表达水平,分析OTULIN表达与胃癌临床病理特征和患者预后的相关性。收集并分析癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库和基因表达综合数据库(Gene Expression Omnibus database,GEO)中的胃癌数据验证上述结论。采用CRISPR/Cas9基因编辑技术构建敲除OTULIN表达的胃癌MKN45和AGS细胞并用蛋白质印迹法检测基因敲除效率;采用CCK-8法和软琼脂克隆检测敲除OTULIN表达对MKN45和AGS细胞增殖的影响。蛋白免疫沉淀-质谱技术筛选OTULIN和线性泛素分子(INT-Ub.7KR)的共同互作蛋白,发现线性泛素化修饰底物蛋白。利用丙酮酸激酶(pyruvate kinase,PK)活性试剂盒检测敲除OTULIN表达后糖酵解限速酶的活性变化,乳酸定量试剂盒检测乳酸生成情况。最后采用免疫共沉淀及蛋白质印迹法验证OTULIN对底物蛋白线性泛素化作用。结果:免疫组织化学法检测结果显示,OTULIN在胃癌组织中的表达水平明显高于正常胃黏膜组织(P=0.0041),肿瘤组织中OTULIN高表达者生存期较短(P=0.0077)。TCGA和GEO数据库数据分析也显示胃癌组织OTULIN表达水平升高(P<0.05),且OTULIN高表达与患者不良预后相关(P=0.011)。统计结果显示,OTULIN高表达与TNM分期晚密切相关(P=0.0273),预测患者较短生存期(P=0.04)。敲除OTULIN基因可显著抑制胃癌细胞的增殖能力(P均<0.001),降低胃癌细胞中PK活性和乳酸生成水平(P均<0.01)。OTULIN可结合糖酵解途径的多个限速酶并下调它们的线性泛素化水平,包括丙酮酸激酶M1(pyruvate kinase M1,PKM1)和PKM2以及乳酸脱氢酶A(lactate deh
Objective:To examine the expression of OTU domain deubiquitinase with linear linkage specificity(OTULIN)in gastric cancer tissues and explore the impact of OTULIN silencing on the proliferation of gastric cancer MKN45 and AGS cells as well as its underlying mechanisms.Methods:Immunohistochemical staining was performed to detect the expression level of OTULIN in 73 gastric cancer tissues and 24 normal gastric mucosa.The association between OTULIN expression and the prognosis as well as the clinicopathological features of gastric cancer patients was analyzed.The above results were validated using public data from The Cancer Genome Atlas(TCGA)database and Gene Expression Omnibus(GEO)database.CRISPR/Cas9 gene editing technology was used to construct OTULIN-knockout gastric cancer cells MKN45 and AGS.The efficiency of gene knockout was validated by Western blotting.The effects of OTULIN knockout on the proliferation of gastric cancer cells MKN45 and AGS were assessed by CCK-8 assay and soft agar colony formation assay.Immunoprecipitation-mass spectrometry technique was exploited to identify potential protein substrates interacting with OTULIN and linear ubiquitin molecule INT-Ub.7KR.The changes in the activity of rate-limiting enzymes for glycolysis were measured using pyruvate kinase(PK)activity assay kit and lactate production was analyzed by lactate colorimetric/fluorometric assay kit in OTULIN-depleted cells.The effect of OTULIN on substrate linear ubiquitination was evaluated using co-immunoprecipitation and Western blotting.Results:The expression level of OTULIN in gastric cancer tissues was higher than that in normal gastric mucosa(P=0.0041)as revealed by immunohistochemical analysis.Patients with higher OTULIN expression in the cancer tissues had a lower suvival time(P=0.0077).Analysis of datasets from TCGA and GEO databases also confirmed that OTULIN was highly expressed in gastric tissues(P<0.05)and high OTULIN expression was associated with poor prognosis(P=0.011).Statistical analysis also showed that highe
作者
温海慧
顾玉超
刘琴
王斌
WEN Haihui;GU Yuchao;LIU Qin;WANG Bin(Department of Medicine,Ocean University of China,Ocean University of China,Qingdao 266003,Shandong Province,China;Department of Gastroenterology,Chongqing Key Laboratory of Digestive Malignancies,Daping Hospital,Army Medical University(Third Military Medical University),Chongqing,400042,China;Institute of Pathology and Southwest Cancer Center,and Key Laboratory of Tumor Immunopathology of Ministry of Education of China,Southwest Hospital,Army Medical University(Third Military Medical University),Chongqing 400038,China)
出处
《肿瘤》
CAS
北大核心
2023年第12期905-919,共15页
Tumor
基金
国家自然科学基金资助项目(81822032,91959111,81872027)
重庆市自然科学基金项目(cstc2019jcyjjqX0027,cstc2021jcyj-msxmX0340)
肿瘤免疫病理学教育部重点实验室开放课题(2022JSZ807)
