Zhang D, Zou X, Song Y, Wu D
Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
Hepatology Unit and Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
Nan Fang Yi Ke Da Xue Xue Bao. 2021 Feb 25;41(2):193-199. doi: 10.12122/j.issn.1673-4254.2021.02.05.
To investigate the effect of long non-coding RNA UPK1A-AS1 on glycolysis of hepatocellular carcinoma cells and its underlying molecular mechanisms.
A hepatocellular carcinoma (HCC) cell line with lentivirus-mediated stable UPK1A-AS1 overexpression and the cells infected with a negative control lentiviral vector were cultured under normoxic (21% O) or hypoxic (1% O) conditions for 24 h. The effect of UPK1A-AS1 overexpression on glycolysis of the HCC cells was examined. The expressions of glycolysis-related genes HIF1A, GLUT1, HK1, HK2 and PGK1 were detected by qRTPCR, and the effect of UPK1A-AS1 overexpression on HRE activity was detected by dual luciferase report assay. The HCC cells were treated with cycloheximide to detect the effect of UPK1A-AS1 overexpression on the stability of HIF-1 protein. Immunoprecipitation assay was used to analyze the changes in ubiquitin modification of HIF-1 protein in response to UPK1A-AS1 overexpression. The effects of UPK1A-AS1 overexpression and RNA interference of HIF-1 expression on glucose consumption, lactate production and expressions of HRE activity and glycolysis-related genes (HK1, HK2 and PGK1) were examined in the HCC cells.
Compared with the control group, overexpression of UPK1A-AS1 significantly promoted glucose consumption and lactate production in HCC cells under both normoxic and hypoxic conditions ( < 0.05). Overexpression of UPK1A-AS1 significantly increased the expression of glycolysis-related genes including HIF1A, GLUT1, HK1, HK2 and PGK1. Upregulation of UPK1A-AS1 obviously promoted the transcriptional activity of HRE ( < 0.05). Western blotting showed that UPK1A-AS1 overexpression obviously increased the stability of HIF-1 protein and significantly reduced ubiquitin modification of HIF-1. Downregulation of HIF-1 obviously reversed the effect of UPK1A-AS1 overexpression in promoting glucose consumption, lactate production and HRE luciferase activity. Silencing HIF-1 also suppressed the upregulation of glycolysis-related gene expressions induced by UPK1A-AS1 overexpression ( < 0.05).
The long noncoding RNA UPK1A-AS1 upregulates the expression of glycolysis-related genes by stabilizing the expression of HIF-1, thereby promoting glycolysis level in HCC cells.
探讨长链非编码RNA UPK1A-AS1对肝癌细胞糖酵解的影响及其潜在分子机制。
将慢病毒介导的UPK1A-AS1稳定过表达的肝癌细胞系及感染阴性对照慢病毒载体的细胞在常氧(21% O₂)或低氧(1% O₂)条件下培养24小时。检测UPK1A-AS1过表达对肝癌细胞糖酵解的影响。通过qRT-PCR检测糖酵解相关基因HIF1A、GLUT1、HK1、HK2和PGK1的表达,通过双荧光素酶报告基因检测法检测UPK1A-AS1过表达对缺氧反应元件(HRE)活性的影响。用放线菌酮处理肝癌细胞,检测UPK1A-AS1过表达对HIF-1蛋白稳定性的影响。采用免疫沉淀试验分析UPK1A-AS1过表达对HIF-1蛋白泛素化修饰的影响。检测UPK1A-AS1过表达及HIF-1表达的RNA干扰对肝癌细胞葡萄糖消耗、乳酸生成以及HRE活性和糖酵解相关基因(HK1、HK2和PGK1)表达的影响。
与对照组相比,UPK1A-AS1过表达在常氧和低氧条件下均显著促进肝癌细胞的葡萄糖消耗和乳酸生成(P<0.05)。UPK1A-AS1过表达显著增加包括HIF1A、GLUT1、HK1、HK2和PGK1在内的糖酵解相关基因的表达。UPK1A-AS1上调明显促进HRE的转录活性(P<0.05)。蛋白质免疫印迹法显示,UPK1A-AS1过表达明显增加HIF-1蛋白的稳定性,并显著降低HIF-1的泛素化修饰。HIF-1下调明显逆转了UPK1A-AS1过表达在促进葡萄糖消耗、乳酸生成及HRE荧光素酶活性方面的作用。沉默HIF-1也抑制了UPK1A-AS1过表达诱导的糖酵解相关基因表达上调(P<0.05)。
长链非编码RNA UPK1A-AS1通过稳定HIF-1的表达上调糖酵解相关基因的表达,从而促进肝癌细胞的糖酵解水平。