Aim To investigate whether diallyl disul¬fide ( DADS) downregulates X-linked inhibitor of ap- optosis protein ( XIAP) through miR-7 , inhibiting the proliferation, migration anrl invasion of gastric eaneer SGC7901 eel Is.Methods Gastric eaneer SGC7901 eell line overexpressing XIAP was established.qRT- PCR and Western blot were used to deteet the effeet of DADS on XIAP expression in overexpressed eells.CCK-8 and plate elone formation assay were used to analyze the effeet of DADS on the proliferation of XIAP overexpressing eells.Wound healing and Transwell ex¬periments were employed to analyze the effeets of DADS on the migration and invasion of XIAP overex¬pressing eells.qRT-PCR was used to deteet the effeet of DADS on the expression of miR-7.Negative regula¬ tion of miR-7 on XIAP was verified by using dual lucif- erase reporter gene assay, qRT-PCR ,anrl Western blot.Results XIAP overexpression enhanced the prolifera¬tion , migration and invasion of SGC7901 cells.DADS downregulated XIAP and inhibited the proliferation, mi¬gration and invasion of XIAP overexpressing cells.DADS upregulated miR-7 expression.miR-7 bound and regulated XIAP 3 'UTR directly.Overexpression of miR-7 decreased XIAP expression,while knockdown of miR-7 increased XIAP expression.Conclusion DADS downregulates XIAP through miR-7 to inhibit SGC7901 cell proliferation, migration and invasion.

[摘 要] 目的：采用生物信息学方法分析E3泛素连接酶（HECW2）在胃腺癌组织中的表达及其临床意义，为寻找胃腺癌诊断和预后生物标志物提供新的线索。方法：用R语言分析HECW2在泛癌中的表达及其与泛癌预后的关系。借助UCSC Xena、HPA、Kaplan-Meier Plotter等数据库分析HECW2在胃腺癌组织中的表达及其与临床病理特征之间的关系。采用WB法检测中国人胃腺癌组织及其癌旁组织中HECW2蛋白水平以验证数据库中的分析结果。借助TIMER和Cibersort数据库分析HECW2与胃腺癌免疫浸润的关系。通过LinkedOmics数据库对胃腺癌中HECW2进行GO功能分析和KEGG信号通路富集分析及相关性基因分析。结果：生物信息学分析结果表明，33种不同类型肿瘤中，包括胃腺癌在内的12种肿瘤中HECW2呈显著高表达（均P<0.05），WB法结果显示，中国人胃腺癌组织中HECW2也呈显著高表达（P<0.05）。HECW2表达水平越高，胃腺癌患者OS越短，包括CD4+ T细胞、巨噬细胞、中性粒细胞和树突状细胞在内的免疫细胞浸润丰度越高（均P˂0.01）。此外，HECW2相关信号通路主要富集于细胞外基质受体相互作用、黏着斑、细胞黏附和氧化磷酸化等生理病理过程（均P˂0.01）。结论：HECW2在胃腺癌组织中呈显著高表达且其与胃腺癌预后不良和免疫细胞浸润密切相关，有成为胃腺癌预后标志物和治疗靶点的潜力。