HIF-1α通过调控脂代谢关键基因促进肾癌细胞的侵袭

HIF-1α promotes invasion of renal cell carcinoma via regulation of lipid-metabolism related genes

目的:脂肪代谢在肾癌的发生、发展过程中至关重要。缺氧诱导因子-1α(HIF-1α)被认为是肾癌发生发展过程中关键的基因之一,其参与调控肾癌的侵袭转移过程。本研究探讨肾癌细胞侵袭过程中HIF-1α与脂肪代谢相关基因的关系。方法:采用免疫组织化学法检测人肾癌组织内HIF-1α、SCD1及FASN的表达,分析各基因之间的相关性。采用HIF-1α过表达质粒或敲除shRNA沉默正常肾脏细胞HK-2及肾癌细胞ACHN内HIF-1α后,运用real-time PCR及Western blot技术检测脂肪代谢相关基因SCD1及FASN的表达改变情况。采用Transwell实验检测细胞体外侵袭能力,并运用SCD1及FASN的siRNA行基因沉默后,检测此两种基因对细胞侵袭能力的影响。结果:免疫组织化学结果显示SCD1及FASN在肾癌组织中的表达与HIF-1α呈显著正相关。HIF-1α过表达质粒能明显上调SCD1和FASN mRNA及蛋白的表达水平,反之,HIF-1αshRNA则明显抑制两种基因的表达。HIF-1α促进肾癌细胞ACHN的体外侵袭能力,而同时转染SCD1及FASN siRNA沉默基因表达后,细胞的侵袭能力减弱。结论:调控肾癌脂肪代谢的基因SCD1及FASN在HIF-1α所调控的肾癌细胞的侵袭过程中发挥重要作用。

Objective：Lipid -metabolism has been shown to play critical role in the development and progression of renal cell carcinoma （RCC）. HIF - 1α is one of the essential genes which promote RCC invasion. The present study is aimed to investigate the potential roles of lipid - metabolism related genes in HIF - 1 α - regulated invasion of RCC cells, nethods：Immunohistochemisuy was used to detect the expression of HIF -1α, SCD1 and FASN in human RCC tissues,and Pearson correlation assay was used to analyze the associations between genes. HIF - 1 α over - ex- pression plasmid and shRNA were transfected into normal kidney cell HK- 2 and RCC cell ACHN, Western blot and real - time PCR were performed to detect the expression of two lipid - metabolism related genes SCDI and FASN. Transwell assay was performed to detect the invasion abilities in vitro in ACHN cells introduced with HIF - 1 αover - expression plasmid, and when specific siRNAs targeting SCD1 and FASN were co -transfected into cells with HIF - 1v over - expression plasmid, cell invasion was again determined. Results： Immunohistochemistry staining showed that the expression of SCD1 and FASN in human RCC tissues were positively correlated with HIF -1α. Over- expression of HIF - 1αsignificantly upregulated the mRNA and protein expression of SCD1 and FASN ,whereas, HIF - 1 α shR- NA decreased SCD1 and FASN expression. HIF - 1α over - expression plasmid promoted ACHN invasion, but when SCD1 and FASN siRNAs were transfected into cells, the invasive ability of cells was ablated. Conclusion：Lipid - metabolism related genes SCD1 and FASN play crucial roles in HIF- 1α regulated invasion of RCC cells.