DAXX在胃癌中的表达定位及其小泛素化修饰对胃癌恶性表型的影响  

The expression and localization of DAXX in gastric cancer and the effect of its SUMO on the malignant phenotype of gastric cancer

作　　者：陈琛斌 黄群佳 谢旺凯 徐剑峰[1] 沈贤[1] 薛向阳[3] 赵志光[2] CHEN Chenbin;HUANG Qunjia;XIE Wangkai;XU Jianfeng;SHEN Xian;XUE Xiangyang;ZHAO Zhiguang(Department of Gastrointestinal Surgery,the Second Affiliated Hospital&Yuying Children’s Hospital of Wenzhou Medical University,Wenzhou 325027,China;Department of Pathology,the Second Affiliated Hospital&Yuying Children’s Hospital of Wenzhou Medical University,Wenzhou 325027,China;Department of Microbiology and Immunology,Institute of Molecular Virology and Immunology,Wenzhou Medical University,Wenzhou 325035,China)

机构地区：[1]温州医科大学附属第二医院育英儿童医院胃肠外科,浙江温州325027 [2]温州医科大学附属第二医院育英儿童医院病理科,浙江温州325027 [3]温州医科大学微生物学与免疫学教研室分子病毒与免疫研究所,浙江温州325035

出　　处：《温州医科大学学报》2020年第10期775-781,共7页Journal of Wenzhou Medical University

基　　金：国家自然科学基金资助项目(81672707,31670922);温州市科技计划项目(Y20170186)。

摘　　要：目的:研究死亡结构域相关蛋白(DAXX)在胃癌中的表达与定位,并探讨小泛素化修饰(SUMO)的DAXX对胃癌细胞恶性表型的影响。方法:生物信息学分析肿瘤基因图谱(TCGA)计划中DAXX在胃癌中的表达与预后;RT-qPCR检测各胃癌细胞系中DAXX的mRNA水平。收集2017年1月至6月温州医科大学附属第二医院育英儿童医院胃癌术后患者20对癌和癌旁组织,免疫组化检测DAXX的表达。CCK-8和划痕实验分别检测DAXX对细胞增殖和迁移的作用。Western blot检测DAXX的核-浆蛋白分布及其对SUMO-2/3的影响。结果:生物信息学分析显示,DAXX在胃癌中的表达水平高于癌旁组织,但其表达高低对患者生存预后无影响(P=0.52);免疫组化结果显示胃癌组织DAXX的阳性率高于癌旁,且在细胞核中高表达;RT-qPCR证实胃癌细胞系中DAXX的mRNA表达量升高。CCK-8和划痕实验提示DAXX明显抑制细胞增殖(P<0.05)并促进细胞迁移(P<0.01)。Western blot显示DAXX核-浆蛋白分布差异,且存在SUMO-2/3修饰。结论:DAXX在胃癌组织中高表达,且主要定位于细胞核。DAXX可能通过与SUMO-2/3结合,抑制胃癌增殖和促进转移。Objective:To explore the expression and localization of DAXX in gastric cancer and the effect of its SUMO-induced DAXX on the malignant phenotype of gastric cancer cells.Methods:The expression and prognosis of DAXX in gastric cancer from TCGA database were analyzed.Real-time quantitative PCR(RT-qPCR)was used to detect the mRNA level of DAXX in gastric cancer cell lines.Samples of gastric cancer and the adjacent tissue were collected from 20 patients after surgery between January and June 2017 in the Second Affiliated Hospital&Yuying Children’s Hospital of Wenzhou Medical University.The expression and localization of DAXX were detected by immunohistochemistry.CCK-8 and wound healing assays were used to examine the effect of DAXX on cell proliferation and migration,respectively.Western blot was used to detect the distribution of DAXX and its correlation with SUMO-2/3.Results:Bioinformatics analysis showed that the expression level of DAXX in gastric cancer was higher than that in adjacent normal tissues,but had no effect on the survival prognosis of patients(P=0.52).The immunohistochemical results showed that the positive rate of DAXX expression in gastric cancer tissues(65.0%)was higher than that in cancer tissues(50%).And DAXX was mainly expressed in the nuclear.RT-qPCR confirmed that the mRNA expression level of DAXX in gastric cancer cell lines was significantly increased.The results of CCK-8 assay indicated that DAXX significantly inhibited cell proliferation(P<0.05),while the wound healing assay indicated that DAXX significantly promoted cell migration(P<0.01).Western blot showed differences in the distribution of DAXX and there was a significant SUMO-2/3 modification in DAXX.Conclusion:DAXX is highly expressed in gastric cancer and is mainly localized in the nucleus.DAXX may affect nuclear-plasma transport by inhibiting gastric cancer cell proliferation and promoting metastasis via interaction with SUMO2/3.

关 键 词：死亡结构域相关蛋白 胃癌 小泛素化修饰 亚细胞定位 

分 类 号：R735.2[医药卫生—肿瘤]