Department of Nuclear Medicine, The Second Affiliated Hospital of Nanchang University, 1 Minde Road, Nanchang 330006, Jiangxi Province, P. R. China.
Department of Gastroenterology, The Second Affiliated Hospital of Nanchang University, 1 Minde Road, Nanchang 330006, Jiangxi Province, P. R. China.
Cell Biol Int. 2019 Jan;43(1):44-55. doi: 10.1002/cbin.11077.
Radioresistance is a major obstacle in hepatocellular carcinoma (HCC) radiotherapy. Aberrant expression of long non-coding RNA (lncRNA) has been postulated to be implicated in the development of HCC radioresistance. We investigated the role of lncRNA nuclear enriched abundant transcript 1_2 (NEAT1_2) in radioresistance of HCC and its molecular mechanism in this study. We found that NEAT1_2 and WEE1 were upregulated, and miR-101-3p was downregulated in HCC tissues, as well as HCC cell lines. Downregulation of WEE1 sensitized the radiosensitivity of HCC cells, as evidenced by decreased survival fractions of Huh7 and PLC5 cells and increased percentage of apoptotic cells. Also, knockdown of NEAT1_2 exerted a reinforcing effect on the radiosensitivity of HCC cells. In addition, WEE1 was confirmed as a direct target of miR-101-3p. Upregulation of miR-101-3p obviously decreased the mRNA and protein levels of WEE1 compared with that in the miR-NC group, while transfection of anta-miR-101-3p presented the opposite effects. In parallel, NEAT1_2 was identified to interact with miR-101-3p, and NEAT1_2 upregulated the expression of WEE1 in Huh7 cells through sponging miR-101-3p. Besides, the reinforcing effect of NEAT1_2 silencing could be attenuated by downregulation of miR-101-3p. To conclude, our results support the concept that downregulation of lncRNA NEAT1_2 radiosensitizes hepatocellular carcinoma cells through regulation of miR-101-3p/WEE1 axis.
放射抵抗是肝细胞癌 (HCC) 放射治疗的主要障碍。长链非编码 RNA (lncRNA) 的异常表达被认为与 HCC 放射抵抗的发生有关。在本研究中,我们研究了 lncRNA 核丰富丰富转录物 1_2 (NEAT1_2) 在 HCC 放射抵抗中的作用及其分子机制。我们发现,在 HCC 组织和 HCC 细胞系中,NEAT1_2 和 WEE1 上调,miR-101-3p 下调。下调 WEE1 可增强 HCC 细胞的放射敏感性,表现为 Huh7 和 PLC5 细胞的存活分数降低,凋亡细胞比例增加。此外,下调 NEAT1_2 对 HCC 细胞的放射敏感性也有增强作用。另外,WEE1 被证实是 miR-101-3p 的直接靶标。与 miR-NC 组相比,miR-101-3p 的上调明显降低了 WEE1 的 mRNA 和蛋白水平,而 anta-miR-101-3p 的转染则呈现相反的效果。平行地,NEAT1_2 被鉴定为与 miR-101-3p 相互作用,并且 NEAT1_2 通过海绵 miR-101-3p 上调 Huh7 细胞中 WEE1 的表达。此外,下调 miR-101-3p 可以减弱 NEAT1_2 沉默的增强作用。总之,我们的结果支持下调 lncRNA NEAT1_2 通过调节 miR-101-3p/WEE1 轴放射增敏肝细胞癌细胞的概念。