RSUME和HIF-1α/VEGF通路与垂体腺瘤侵袭之间的关系

Relationship of RSUME and HIF-1α/VEGFA pathways with invasion of pituitary adenoma

目的 :探讨RSUME(RWD containing sumoylation enhancer)和缺氧诱导因子-1α(hypoxia-inducible factor-1alpha,HIF-1α)/血管内皮生长因子(vascular endothelial growth factor,VEGF)通路与垂体腺瘤侵袭之间的关系。方法:应用实时荧光定量PCR法检测垂体腺瘤组织中RSUME、HIF-1α和VEGF-A mRNA的表达水平,蛋白质印迹法检测垂体腺瘤组织中小泛素相关修饰因子-1(small ubiquitin-related modifi ers-1,SUMO-1)、HIF-1α和VEGF-A蛋白的表达水平。将靶向RSUME基因的小干扰RNA(small interfering RNA,siRNA)转染至小鼠垂体腺瘤AtT-20细胞后,实时荧光定量PCR法检测细胞中RSUME、HIF-1α和VEGF-A mRNA的表达水平,蛋白质印迹法检测细胞中SUMO-1、HIF-1α和VEGF-A蛋白的表达水平,Transwell法检测细胞侵袭能力的改变。结果:侵袭性垂体腺瘤组织中RSUME、HIF-1α、VEGF-A mRNA的表达水平和SUMO-1、HIF-1α、VEGF-A蛋白的表达水平明显高于非侵袭性垂体腺瘤组织和正常垂体组织(P均<0.05)。并且,侵袭性垂体腺瘤组织中SUMO-1与HIF-1α的表达呈正相关(r=0.687,P<0.05),HIF-1α与VEGF-A的表达呈正相关(r=0.773,P<0.05)。RSUME siRNA转染组AtT-20细胞中RSUME和VEGF-A mRNA以及SUMO-1、HIF-1α和VEGF-A蛋白的表达水平均明显低于转染阴性对照siRNA组和未转染的空白对照组(P均<0.05)。RSUME siRNA转染组AtT-20细胞的侵袭能力被明显抑制(P<0.05)。结论:RSUME可能通过增强HIF-1α/VEGF通路的作用而促进垂体腺瘤的侵袭。沉默RSUME基因可抑制垂体腺瘤细胞的侵袭。

Objective： To investigate the relationships of RWD-containing sumoylation enhancer（RSUME） and hypoxia-inducible factor-1α（HIF-1α）/vascular endothelial growth factor（VEGF） pathway with invasion of pituitary adenoma.Methods： The expression levels of RSUME, HIF-1α and VEGF-A mRNAs in human pituitary adenoma tissues were detected by real-time fluorescence quantitative-PCR. The expression levels of small ubiquitin-related modifier-1（SUMO-1）, HIF-1α and VEGF-A proteins in pituitary adenoma tissues were detected by Western blotting. Aftert ransfecting with small interfering RNA（siRNA）-targeting RSUME into murine pituitary adenoma AtT-20 cells, the expression levels of RSUME, HIF-1α and VEGF-A mRNAs as well as SUMO-1, HIF-1α and VEGF-A proteins were detected by real-time fluorescence quantitative-PCR and Western blotting, respectively. The invasion ability was measured by Transwell assay.Results： The expression levels of RSUME, HIF-1α and VEGF-A mRNAs as well as SUMO-1, HIF-1α and VEGF-A proteins in invasive pituitary adenoma tissues were significantly higher than those in non-invasive pituitary adenoma tissues and normal pituitaryt issues（all P 〈 0.05）.The SUMO-1 expression was positively correlated with HIF-1α expression in invasive pituitary adenoma tissues（r = 0.687, P 〈 0.05）, and HIF-1α expression was positively correlated with VEGF-A expression（r = 0.773, P 〈 0.05）. The expression levels of RSUME and VEGF-A mRNAs as well as SUMO-1, HIF-1α and VEGF-A proteins in AtT-20 cells after transfection with RSUME siRNA were signif cantly lower than those in the negative control group（AtT-20 cells transfected with negative control siRNA） and the blank controgl roup（AtT-20 cells without any transfection）（all P 〈 0.05）. The invasion ability of AtT-20 cells after transfection with RSUME siRNA was significantly inhibited（P 〈 0.05）.Conclusion： RSUME can promote the invasion of pituitary adenoma by regulating HIF-1 α/VEGF pathway. Silencing of RSUME gene may inhibit the invasion of pituitary adenoma cells.