信号转导和转录激活因子4通过波形蛋白影响肾癌进展

Signal transducer and activator of transcription 4 influences renal cancer progression through vimentin

目的探讨信号转导和转录激活因子4(STAT4)在肾透明细胞癌中的表达及其机制。方法基于基因表达综合数据库(GEO)数据库,比较肾癌中STAT4的表达差异。收集2018年6月至2022年1月联勤保障部队第九八〇医院收治的72例肾癌患者,实时荧光定量聚合酶联反应(qRT-PCR)及免疫组织化学(IHC)法检测肾癌中STAT4的表达。细胞的活力测定(MTS)法检测增殖活性,划痕实验检测迁移能力,Transwell小室检测侵袭能力。染色体免疫共沉淀(ChIP)和荧光素酶实验验证STAT4可作为转录因子与波形蛋白(VIM)结合。两组间比较采用t检验,多组间比较采用单因素方差分析。结果STAT4 mRNA在肾癌中高于正常组织(2.671±2.054比1.012±0.174,t=5.004,P<0.01),STAT4蛋白的阳性率高于正常组织[73.6%(53/72)比31.9%(23/72),χ^(2)=25.077,P<0.01]。将STAT4敲低质粒转染到786-O中,sh-STAT4组的增殖能力降低(2.050±0.139比1.606±0.018,t=6.339,P<0.01),迁移能力下降(0.303±0.050比0.537±0.050,t=-5.678,P<0.01),侵袭能力受到抑制(820.667±16.563比374.667±17.156,t=32.394,P<0.01)。荧光素酶实验及ChIP实验发现STAT4与VIM启动子结合,调控VIM转录表达。结论STAT4在肾透明细胞癌中高表达,并促进肾癌细胞的增殖、迁移和侵袭。STAT4可作为VIM的上游转录因子参与肾癌的发生发展。

Objective To investigate the expression and mechanism of signal transducer and activator of transcription 4(STAT4)in renal cell carcinoma(RCC).Methods The differential expression of STAT4 in RCC tissues was compared based on the Gene Expression Omnibus(GEO)database.A total of 72 patients with RCC admitted to The 980th Hospital of the Joint Logistics Support Force of PLA from June 2018 to January 2022 were collected,and the STAT4 expression in RCC tissue was detected by quantitative real-time fluorescence polymerase chain reaction(qRT-PCR)and immunohistochemistry(IHC).Cell viability assay(MTS)was used to detect cell proliferation activity,cell migration was detected by scratch assay,and Transwell assay was used to detect cell invasion.Chromosome immunoprecipitation(ChIP)and dual luciferase assays verified that STAT4 could bind to VIM as a transcription factor.Comparisons between two groups were made by t-test,and comparisons between multiple groups were performed by one-way ANOVA.Results The expression of STAT4 mRNA in RCC tissue was higher than in the normal tissue(2.671±2.054 vs.1.012±0.174,t=5.004,P<0.01).The positive rate of STAT4 protein in RCC tissue was higher than in the normal tissue[73.6%(53/72)vs.31.9%(23/72),χ^(2)=25.077,P<0.01].MTS confirmed that the proliferation ability in sh-STAT4 group was reduced(2.050±0.139 vs.1.606±0.018,t=6.339,P<0.01).Scratch assay revealed that the migration ability was reduced(0.303±0.050 vs.0.537±0.050,t=-5.678,P<0.01),and Transwell assay showed that the invasion ability was inhibited(820.667±16.563 vs.374.667±17.156,t=32.394,P<0.01)in sh-STAT4 group.The dual luciferase assay and ChIP assay showed that STAT4 was bound to the upstream promoter region of VIM and regulated VIM transcriptional expression.Conclusion STAT4 is highly expressed and promotes the proliferation,migration and invasion of RCC cells.STAT4 may participate in the pathogenesis of RCC as an upstream transcription factor of VIM.