目的：探讨长链非编码RNA（long non-coding RNA ，lncRNA）肺癌相关转录物1（lung cancer associated transcript 1，LUCAT1）对肾透明细胞癌(clear cell renal cell carcinoma，ccRCC)786-O 细胞的增殖和迁移能力的影响及其作用机制。方法：选取2013 年6 月至2017 年6 月宜昌市第一人民医院泌尿外科行手术切除的40 例ccRCC患者癌组织及相应的癌旁组织样本，组织均经病理检查诊断明确。ccRCC细胞株786-O、ACHN、UM-RC-2 及正常肾上皮细胞系KiMA培养完成后，用qPCR法检测ccRCC组织和细胞株中miR-199-a-5p、HIF-1α 和LUCAT1T mRNA的表达，用CCK-8 实验检测786-O 细胞的增殖能力，Transwell 法检测786-O 细胞的迁移能力，双荧光素酶报告基因实验验证LUCAT1 与miR-199a-5p 的靶向作用关系，Western blotting 实验检测LUCAT1、miR-199a-5p 对HIF-1α 蛋白表达的影响。结果：LUCAT1 在ccRCC组织和细胞系786-O、ACHN和UM-RC-2 中呈高表达（均P<0.01），敲低LUCAT1 后可明显抑制786-O 细胞的增殖和迁移（均P<0.01）。miR-199a-5p 在ccRCC 组织和细胞系中呈低表达（均P<0.01），StarBase 数据库分析结果显示LUCAT1含有miR-199a-5p的保守目标位点，miR-199a-5p对LUCAT1-Wt的报告活性具有明显的抑制作用（P<0.01）；敲低LUCAT1可明显降低miR-199a-5p的表达（P<0.01）。LUCAT1 在转染miR-199a-5p 模拟物的786-O细胞中呈低表达，但在LUCAT1+miR-199a-5p 模拟物共转染的786-O细胞中出现逆转（P<0.05 或P<0.01）。转染miR-199a-5p 模拟物的786-O 细胞中HIF-1α mRNA 和蛋白表达水平升高，而LUCAT1 过表达可逆转该效应（P<0.05 或P<0.01）。转染miR-199a-5p模拟物抑制786-O 细胞的增殖和迁移，而转染LUCAT1 可部分消除转染miR-199a-5p 模拟物对786-O 细胞增殖和迁移的影响(P<0.05或P<0.01)。结论：lncRNA LUCAT1通过靶向调节miR-199a-5p/HIF-1α 的表达从而在ccRCC中发挥促癌效应。

Objective: To investigate the effect of long non-coding RNA (lncRNA) lung cancer associated transcript 1 (LUCAT1) on proliferation and migration of clear cell renal cell carcinoma (ccRCC) 786-O cells and the underlying mechanism. Methods: A total of 40 pairs of pathologically confirmed tumor tissues and corresponding adjacent normal tissues from ccRCC patients, who underwent surgical resection in the Department of Urology, the First People's Hospital of Yichang during June 2013 and June 2017, were selected for this study. ccRCC cell lines (786-O, ACHN, UM-RC-2) and normal renal epithelial KiMA cells were also used in this study. qPCR was used to detect the mRNA expressions of LUCAT1, miR-199a-5p and hypoxia inducible fator 1α (HIF-1α) in above mentioned tissues and cell lines; CCK-8 assay was used to evaluate the proliferation of 786-O cells; Transwell assay was used to evaluate the migration of 786-O cells; Dual luciferase reporter gene assay was performed to validate the relationship between LUCAT1 and miR-199a-5p; and Western blotting was conducted to detect the effect of LUCAT1 and miR-199a-5p on the protein expression of HIF-1α . Results:LUCAT1 was significantly up-regulated in ccRCC tissues and cell lines (all P<0.01), and its knockdown significantly inhibited the proliferation and migration of 786-O cells (all P<0.01). miR-199a-5p was low-expressed in ccRCC tissues and cell lines (all P<0.01), Star‐Base analysis showed that LUCAT1 contained a conserved target site for miR-199a-5p. miR-199a-5p exerted significant suppression on the luciferase activity of LUCAT1-Wt (P<0.01), and LUCAT1 knockdown significantly reduced miR-199a-5p expression (P<0.01).LUCAT1 was low-expressed in 786-O cells transfected with miR-199a-5p mimics, however, it was attenuated after co-transfection with LUCAT1. The mRNA and protein expressions of HIF-1α in 786-O cells transfected with miR-199a-5p mimics were up-regulated,which was then reversed by LUCAT1 over-expression (P<0.05 or P<0.01). miR-199a-5p over-expression suppressed the proliferation and migration of 786-O cells, which was partially attenuated by LUCAT1 transfection (P<0.05 or P<0.01). Conclusion: LUCAT1 exerts oncogenic function in ccRCC via regulating miR-199a-5p/HIF-1α axis.

三峡大学教学研究重点项目（No. J2017056）