Department of Oncology, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong Province, China.
J Gastroenterol Hepatol. 2011 Nov;26(11):1630-7. doi: 10.1111/j.1440-1746.2011.06758.x.
MicroRNAs are short noncoding RNA molecules that are responsible for the posttranscriptional regulation of target genes. The aim of this study was to determine whether microRNA-199b-5p (miR-199b) plays a role in the progression and prognosis of hepatocellular carcinoma (HCC), and to elucidate whether hypoxia-inducible factor-1α (Hif1α) is regulated by miR-199b.
In this study, 35 matched HCCs and cirrhosis tissues were assayed for miR-199b and Hif1α expression. To evaluate the role of miR-199b, we assessed cell proliferation rate and clonogenic survival of miR-199b- or negative control-transfected cells by MTT and clone formation assay, respectively. In addition, the regulation of Hif1α by miR-199b was evaluated by Western blotting and luciferase assay. MiR-199b was downregulated in 77% of HCCs, whereas Hif1α protein was upregulated in 69% of cases. A significant inverse correlation between miR-199b and Hif1α was observed in HCCs.
Patients with lower levels of miR-199b expression had poorer overall survival and progression-free survival rates, whereas patients with higher levels of miR-199b expression had better survival. Moreover, miR-199b could restrain cell growth and obviously enhance the radiosensitizing effect of HepG2 cells. MiR-199b and pGL3-Hif1α vector-transfected cells showed suppressed Hif1α protein expression and significant reduced luciferase activity.
Underexpressed miR-199b, which may be via the upregulation of Hif1α in HCCs, is inversely correlated with survival and directly correlated with the malignant status of HCC patients.
微小 RNA（miRNA）是一种短的非编码 RNA 分子，负责靶基因的转录后调控。本研究旨在确定微小 RNA-199b-5p（miR-199b）是否在肝细胞癌（HCC）的进展和预后中发挥作用，并阐明缺氧诱导因子-1α（Hif1α）是否受 miR-199b 调控。
本研究检测了 35 对 HCC 及肝硬化组织中的 miR-199b 和 Hif1α 表达。为评估 miR-199b 的作用，我们通过 MTT 和克隆形成实验分别评估了 miR-199b 或阴性对照转染细胞的细胞增殖率和克隆形成存活能力。此外，通过 Western blot 和荧光素酶实验评估了 Hif1α 受 miR-199b 的调控情况。miR-199b 在 77%的 HCC 中下调，而 Hif1α 蛋白在 69%的病例中上调。在 HCC 中观察到 miR-199b 与 Hif1α 之间存在显著的负相关。
miR-199b 表达水平较低的患者总生存率和无进展生存率较差，而 miR-199b 表达水平较高的患者生存率较好。此外，miR-199b 可抑制细胞生长，并明显增强 HepG2 细胞的放射增敏作用。miR-199b 和 pGL3-Hif1α 载体转染细胞显示 Hif1α 蛋白表达受抑制，荧光素酶活性显著降低。
在 HCC 中，miR-199b 表达下调，可能通过上调 Hif1α，与生存呈负相关，与 HCC 患者的恶性状态直接相关。
